applies new string literal convention in activerecord/test

The current code base is not uniform. After some discussion,
we have chosen to go with double quotes by default.

61 files changed, 843 insertions, 843 deletions

diff --git a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
index 95d1f6b8a3..429919a395 100644
--- a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
   include ConnectionHelper
@@ -102,13 +102,13 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
 
   def test_create_mysql_database_with_encoding
     assert_equal "CREATE DATABASE `matt` DEFAULT CHARACTER SET `utf8`", create_database(:matt)
-    assert_equal "CREATE DATABASE `aimonetti` DEFAULT CHARACTER SET `latin1`", create_database(:aimonetti, {:charset => 'latin1'})
+    assert_equal "CREATE DATABASE `aimonetti` DEFAULT CHARACTER SET `latin1`", create_database(:aimonetti, {:charset => "latin1"})
     assert_equal "CREATE DATABASE `matt_aimonetti` DEFAULT CHARACTER SET `big5` COLLATE `big5_chinese_ci`", create_database(:matt_aimonetti, {:charset => :big5, :collation => :big5_chinese_ci})
   end
 
   def test_recreate_mysql_database_with_encoding
-    create_database(:luca, {:charset => 'latin1'})
-    assert_equal "CREATE DATABASE `luca` DEFAULT CHARACTER SET `latin1`", recreate_database(:luca, {:charset => 'latin1'})
+    create_database(:luca, {:charset => "latin1"})
+    assert_equal "CREATE DATABASE `luca` DEFAULT CHARACTER SET `latin1`", recreate_database(:luca, {:charset => "latin1"})
   end
 
   def test_add_column
@@ -120,7 +120,7 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
   end
 
   def test_drop_table_with_specific_database
-    assert_equal "DROP TABLE `otherdb`.`people`", drop_table('otherdb.people')
+    assert_equal "DROP TABLE `otherdb`.`people`", drop_table("otherdb.people")
   end
 
   def test_add_timestamps
@@ -128,8 +128,8 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
       begin
         ActiveRecord::Base.connection.create_table :delete_me
         ActiveRecord::Base.connection.add_timestamps :delete_me, null: true
-        assert column_present?('delete_me', 'updated_at', 'datetime')
-        assert column_present?('delete_me', 'created_at', 'datetime')
+        assert column_present?("delete_me", "updated_at", "datetime")
+        assert column_present?("delete_me", "created_at", "datetime")
       ensure
         ActiveRecord::Base.connection.drop_table :delete_me rescue nil
       end
@@ -143,8 +143,8 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
           t.timestamps null: true
         end
         ActiveRecord::Base.connection.remove_timestamps :delete_me, { null: true }
-        assert !column_present?('delete_me', 'updated_at', 'datetime')
-        assert !column_present?('delete_me', 'created_at', 'datetime')
+        assert !column_present?("delete_me", "updated_at", "datetime")
+        assert !column_present?("delete_me", "created_at", "datetime")
       ensure
         ActiveRecord::Base.connection.drop_table :delete_me rescue nil
       end
@@ -185,6 +185,6 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
 
     def column_present?(table_name, column_name, type)
       results = ActiveRecord::Base.connection.select_all("SHOW FIELDS FROM #{table_name} LIKE '#{column_name}'")
-      results.first && results.first['Type'] == type
+      results.first && results.first["Type"] == type
     end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb b/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
index abdf3dbf5b..f75cea70a7 100644
--- a/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/bind_parameter_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'models/topic'
+require "models/topic"
 
 module ActiveRecord
   module ConnectionAdapters
diff --git a/activerecord/test/cases/adapters/mysql2/boolean_test.rb b/activerecord/test/cases/adapters/mysql2/boolean_test.rb
index 739bb275ce..2fa39282fb 100644
--- a/activerecord/test/cases/adapters/mysql2/boolean_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/boolean_test.rb
@@ -86,11 +86,11 @@ class Mysql2BooleanTest < ActiveRecord::Mysql2TestCase
   end
 
   def boolean_column
-    BooleanType.columns.find { |c| c.name == 'archived' }
+    BooleanType.columns.find { |c| c.name == "archived" }
   end
 
   def string_column
-    BooleanType.columns.find { |c| c.name == 'published' }
+    BooleanType.columns.find { |c| c.name == "published" }
   end
 
   def emulate_booleans(value)
diff --git a/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb b/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
index 9cb05119a2..5f677626b0 100644
--- a/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/case_sensitivity_test.rb
@@ -7,19 +7,19 @@ class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
   repair_validations(CollationTest)
 
   def test_columns_include_collation_different_from_table
-    assert_equal 'utf8_bin', CollationTest.columns_hash['string_cs_column'].collation
-    assert_equal 'utf8_general_ci', CollationTest.columns_hash['string_ci_column'].collation
+    assert_equal "utf8_bin", CollationTest.columns_hash["string_cs_column"].collation
+    assert_equal "utf8_general_ci", CollationTest.columns_hash["string_ci_column"].collation
   end
 
   def test_case_sensitive
-    assert !CollationTest.columns_hash['string_ci_column'].case_sensitive?
-    assert CollationTest.columns_hash['string_cs_column'].case_sensitive?
+    assert !CollationTest.columns_hash["string_ci_column"].case_sensitive?
+    assert CollationTest.columns_hash["string_cs_column"].case_sensitive?
   end
 
   def test_case_insensitive_comparison_for_ci_column
     CollationTest.validates_uniqueness_of(:string_ci_column, :case_sensitive => false)
-    CollationTest.create!(:string_ci_column => 'A')
-    invalid = CollationTest.new(:string_ci_column => 'a')
+    CollationTest.create!(:string_ci_column => "A")
+    invalid = CollationTest.new(:string_ci_column => "a")
     queries = assert_sql { invalid.save }
     ci_uniqueness_query = queries.detect { |q| q.match(/string_ci_column/) }
     assert_no_match(/lower/i, ci_uniqueness_query)
@@ -27,8 +27,8 @@ class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
 
   def test_case_insensitive_comparison_for_cs_column
     CollationTest.validates_uniqueness_of(:string_cs_column, :case_sensitive => false)
-    CollationTest.create!(:string_cs_column => 'A')
-    invalid = CollationTest.new(:string_cs_column => 'a')
+    CollationTest.create!(:string_cs_column => "A")
+    invalid = CollationTest.new(:string_cs_column => "a")
     queries = assert_sql { invalid.save }
     cs_uniqueness_query = queries.detect { |q| q.match(/string_cs_column/)}
     assert_match(/lower/i, cs_uniqueness_query)
@@ -36,8 +36,8 @@ class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
 
   def test_case_sensitive_comparison_for_ci_column
     CollationTest.validates_uniqueness_of(:string_ci_column, :case_sensitive => true)
-    CollationTest.create!(:string_ci_column => 'A')
-    invalid = CollationTest.new(:string_ci_column => 'A')
+    CollationTest.create!(:string_ci_column => "A")
+    invalid = CollationTest.new(:string_ci_column => "A")
     queries = assert_sql { invalid.save }
     ci_uniqueness_query = queries.detect { |q| q.match(/string_ci_column/) }
     assert_match(/binary/i, ci_uniqueness_query)
@@ -45,8 +45,8 @@ class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
 
   def test_case_sensitive_comparison_for_cs_column
     CollationTest.validates_uniqueness_of(:string_cs_column, :case_sensitive => true)
-    CollationTest.create!(:string_cs_column => 'A')
-    invalid = CollationTest.new(:string_cs_column => 'A')
+    CollationTest.create!(:string_cs_column => "A")
+    invalid = CollationTest.new(:string_cs_column => "A")
     queries = assert_sql { invalid.save }
     cs_uniqueness_query = queries.detect { |q| q.match(/string_cs_column/) }
     assert_no_match(/binary/i, cs_uniqueness_query)
@@ -54,8 +54,8 @@ class Mysql2CaseSensitivityTest < ActiveRecord::Mysql2TestCase
 
   def test_case_sensitive_comparison_for_binary_column
     CollationTest.validates_uniqueness_of(:binary_column, case_sensitive: true)
-    CollationTest.create!(binary_column: 'A')
-    invalid = CollationTest.new(binary_column: 'A')
+    CollationTest.create!(binary_column: "A")
+    invalid = CollationTest.new(binary_column: "A")
     queries = assert_sql { invalid.save }
     bin_uniqueness_query = queries.detect { |q| q.match(/binary_column/) }
     assert_no_match(/\bBINARY\b/, bin_uniqueness_query)
diff --git a/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb b/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
index c8028b6b36..8826ad7fd1 100644
--- a/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/charset_collation_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class Mysql2CharsetCollationTest < ActiveRecord::Mysql2TestCase
   include SchemaDumpingHelper
@@ -8,8 +8,8 @@ class Mysql2CharsetCollationTest < ActiveRecord::Mysql2TestCase
   setup do
     @connection = ActiveRecord::Base.connection
     @connection.create_table :charset_collations, force: true do |t|
-      t.string :string_ascii_bin, charset: 'ascii', collation: 'ascii_bin'
-      t.text :text_ucs2_unicode_ci, charset: 'ucs2', collation: 'ucs2_unicode_ci'
+      t.string :string_ascii_bin, charset: "ascii", collation: "ascii_bin"
+      t.text :text_ucs2_unicode_ci, charset: "ucs2", collation: "ucs2_unicode_ci"
     end
   end
 
@@ -18,32 +18,32 @@ class Mysql2CharsetCollationTest < ActiveRecord::Mysql2TestCase
   end
 
   test "string column with charset and collation" do
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'string_ascii_bin' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "string_ascii_bin" }
     assert_equal :string, column.type
-    assert_equal 'ascii_bin', column.collation
+    assert_equal "ascii_bin", column.collation
   end
 
   test "text column with charset and collation" do
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'text_ucs2_unicode_ci' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "text_ucs2_unicode_ci" }
     assert_equal :text, column.type
-    assert_equal 'ucs2_unicode_ci', column.collation
+    assert_equal "ucs2_unicode_ci", column.collation
   end
 
   test "add column with charset and collation" do
-    @connection.add_column :charset_collations, :title, :string, charset: 'utf8', collation: 'utf8_bin'
+    @connection.add_column :charset_collations, :title, :string, charset: "utf8", collation: "utf8_bin"
 
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'title' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "title" }
     assert_equal :string, column.type
-    assert_equal 'utf8_bin', column.collation
+    assert_equal "utf8_bin", column.collation
   end
 
   test "change column with charset and collation" do
-    @connection.add_column :charset_collations, :description, :string, charset: 'utf8', collation: 'utf8_unicode_ci'
-    @connection.change_column :charset_collations, :description, :text, charset: 'utf8', collation: 'utf8_general_ci'
+    @connection.add_column :charset_collations, :description, :string, charset: "utf8", collation: "utf8_unicode_ci"
+    @connection.change_column :charset_collations, :description, :text, charset: "utf8", collation: "utf8_general_ci"
 
-    column = @connection.columns(:charset_collations).find { |c| c.name == 'description' }
+    column = @connection.columns(:charset_collations).find { |c| c.name == "description" }
     assert_equal :text, column.type
-    assert_equal 'utf8_general_ci', column.collation
+    assert_equal "utf8_general_ci", column.collation
   end
 
   test "schema dump includes collation" do
diff --git a/activerecord/test/cases/adapters/mysql2/connection_test.rb b/activerecord/test/cases/adapters/mysql2/connection_test.rb
index fe610ae951..3fb2b15783 100644
--- a/activerecord/test/cases/adapters/mysql2/connection_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/connection_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
   include ConnectionHelper
@@ -9,7 +9,7 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
   def setup
     super
     @subscriber = SQLSubscriber.new
-    @subscription = ActiveSupport::Notifications.subscribe('sql.active_record', @subscriber)
+    @subscription = ActiveSupport::Notifications.subscribe("sql.active_record", @subscriber)
     @connection = ActiveRecord::Base.connection
   end
 
@@ -20,9 +20,9 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_bad_connection
     assert_raise ActiveRecord::NoDatabaseError do
-      configuration = ActiveRecord::Base.configurations['arunit'].merge(database: 'inexistent_activerecord_unittest')
+      configuration = ActiveRecord::Base.configurations["arunit"].merge(database: "inexistent_activerecord_unittest")
       connection = ActiveRecord::Base.mysql2_connection(configuration)
-      connection.drop_table 'ex', if_exists: true
+      connection.drop_table "ex", if_exists: true
     end
   end
 
@@ -39,7 +39,7 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_no_automatic_reconnection_after_timeout
     assert @connection.active?
-    @connection.update('set @@wait_timeout=1')
+    @connection.update("set @@wait_timeout=1")
     sleep 2
     assert !@connection.active?
 
@@ -49,7 +49,7 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_successful_reconnection_after_timeout_with_manual_reconnect
     assert @connection.active?
-    @connection.update('set @@wait_timeout=1')
+    @connection.update("set @@wait_timeout=1")
     sleep 2
     @connection.reconnect!
     assert @connection.active?
@@ -57,15 +57,15 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_successful_reconnection_after_timeout_with_verify
     assert @connection.active?
-    @connection.update('set @@wait_timeout=1')
+    @connection.update("set @@wait_timeout=1")
     sleep 2
     @connection.verify!
     assert @connection.active?
   end
 
   def test_mysql_connection_collation_is_configured
-    assert_equal 'utf8_unicode_ci', @connection.show_variable('collation_connection')
-    assert_equal 'utf8_general_ci', ARUnit2Model.connection.show_variable('collation_connection')
+    assert_equal "utf8_unicode_ci", @connection.show_variable("collation_connection")
+    assert_equal "utf8_general_ci", ARUnit2Model.connection.show_variable("collation_connection")
   end
 
   def test_mysql_default_in_strict_mode
@@ -92,8 +92,8 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_mysql_sql_mode_variable_overrides_strict_mode
     run_without_connection do |orig_connection|
-      ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { 'sql_mode' => 'ansi' }))
-      result = ActiveRecord::Base.connection.select_value('SELECT @@SESSION.sql_mode')
+      ActiveRecord::Base.establish_connection(orig_connection.deep_merge(variables: { "sql_mode" => "ansi" }))
+      result = ActiveRecord::Base.connection.select_value("SELECT @@SESSION.sql_mode")
       assert_no_match %r(STRICT_ALL_TABLES), result
     end
   end
@@ -107,7 +107,7 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
 
   def test_passing_flags_by_array_to_adapter
     run_without_connection do |orig_connection|
-      ActiveRecord::Base.establish_connection(orig_connection.merge({flags: ['COMPRESS'] }))
+      ActiveRecord::Base.establish_connection(orig_connection.merge({flags: ["COMPRESS"] }))
       assert_equal ["COMPRESS", "FOUND_ROWS"], ActiveRecord::Base.connection.raw_connection.query_options[:flags]
     end
   end
@@ -130,14 +130,14 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
   end
 
   def test_logs_name_show_variable
-    @connection.show_variable 'foo'
+    @connection.show_variable "foo"
     assert_equal "SCHEMA", @subscriber.logged[0][1]
   end
 
   def test_logs_name_rename_column_sql
     @connection.execute "CREATE TABLE `bar_baz` (`foo` varchar(255))"
     @subscriber.logged.clear
-    @connection.send(:rename_column_sql, 'bar_baz', 'foo', 'foo2')
+    @connection.send(:rename_column_sql, "bar_baz", "foo", "foo2")
     assert_equal "SCHEMA", @subscriber.logged[0][1]
   ensure
     @connection.execute "DROP TABLE `bar_baz`"
@@ -155,14 +155,14 @@ class Mysql2ConnectionTest < ActiveRecord::Mysql2TestCase
     released_lock = @connection.release_advisory_lock(lock_name)
     assert released_lock, "expected release_advisory_lock to return true but it didn't"
 
-    assert test_lock_free(lock_name), 'expected the test lock to be available after releasing'
+    assert test_lock_free(lock_name), "expected the test lock to be available after releasing"
   end
 
   def test_release_non_existent_advisory_lock
     lock_name = "fake lock'n'name"
     released_non_existent_lock = @connection.release_advisory_lock(lock_name)
     assert_equal released_non_existent_lock, false,
-      'expected release_advisory_lock to return false when there was no lock to release'
+      "expected release_advisory_lock to return false when there was no lock to release"
   end
 
   protected
diff --git a/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb b/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
index e349c67c93..135789a57d 100644
--- a/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/datetime_precision_quoting_test.rb
@@ -5,23 +5,23 @@ class Mysql2DatetimePrecisionQuotingTest < ActiveRecord::Mysql2TestCase
     @connection = ActiveRecord::Base.connection
   end
 
-  test 'microsecond precision for MySQL gte 5.6.4' do
-    stub_version '5.6.4'
+  test "microsecond precision for MySQL gte 5.6.4" do
+    stub_version "5.6.4"
     assert_microsecond_precision
   end
 
-  test 'no microsecond precision for MySQL lt 5.6.4' do
-    stub_version '5.6.3'
+  test "no microsecond precision for MySQL lt 5.6.4" do
+    stub_version "5.6.3"
     assert_no_microsecond_precision
   end
 
-  test 'microsecond precision for MariaDB gte 5.3.0' do
-    stub_version '5.5.5-10.1.8-MariaDB-log'
+  test "microsecond precision for MariaDB gte 5.3.0" do
+    stub_version "5.5.5-10.1.8-MariaDB-log"
     assert_microsecond_precision
   end
 
-  test 'no microsecond precision for MariaDB lt 5.3.0' do
-    stub_version '5.2.9-MariaDB'
+  test "no microsecond precision for MariaDB lt 5.3.0" do
+    stub_version "5.2.9-MariaDB"
     assert_no_microsecond_precision
   end
 
diff --git a/activerecord/test/cases/adapters/mysql2/enum_test.rb b/activerecord/test/cases/adapters/mysql2/enum_test.rb
index 35dbc76d1b..9f51223d58 100644
--- a/activerecord/test/cases/adapters/mysql2/enum_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/enum_test.rb
@@ -5,22 +5,22 @@ class Mysql2EnumTest < ActiveRecord::Mysql2TestCase
   end
 
   def test_enum_limit
-    column = EnumTest.columns_hash['enum_column']
+    column = EnumTest.columns_hash["enum_column"]
     assert_equal 8, column.limit
   end
 
   def test_should_not_be_blob_or_text_column
-    column = EnumTest.columns_hash['enum_column']
+    column = EnumTest.columns_hash["enum_column"]
     assert_not column.blob_or_text_column?
   end
 
   def test_should_not_be_unsigned
-    column = EnumTest.columns_hash['enum_column']
+    column = EnumTest.columns_hash["enum_column"]
     assert_not column.unsigned?
   end
 
   def test_should_not_be_bigint
-    column = EnumTest.columns_hash['enum_column']
+    column = EnumTest.columns_hash["enum_column"]
     assert_not column.bigint?
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/explain_test.rb b/activerecord/test/cases/adapters/mysql2/explain_test.rb
index b783b5fcd9..7916921e5a 100644
--- a/activerecord/test/cases/adapters/mysql2/explain_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/explain_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
+require "models/developer"
+require "models/computer"
 
 class Mysql2ExplainTest < ActiveRecord::Mysql2TestCase
   fixtures :developers
diff --git a/activerecord/test/cases/adapters/mysql2/json_test.rb b/activerecord/test/cases/adapters/mysql2/json_test.rb
index 9c3fef1b59..87b6a07f65 100644
--- a/activerecord/test/cases/adapters/mysql2/json_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/json_test.rb
@@ -1,5 +1,5 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+require "cases/helper"
+require "support/schema_dumping_helper"
 
 if ActiveRecord::Base.connection.supports_json?
 class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
@@ -7,7 +7,7 @@ class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
   self.use_transactional_tests = false
 
   class JsonDataType < ActiveRecord::Base
-    self.table_name = 'json_data_type'
+    self.table_name = "json_data_type"
 
     store_accessor :settings, :resolution
   end
@@ -15,9 +15,9 @@ class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
   def setup
     @connection = ActiveRecord::Base.connection
     begin
-      @connection.create_table('json_data_type') do |t|
-        t.json 'payload'
-        t.json 'settings'
+      @connection.create_table("json_data_type") do |t|
+        t.json "payload"
+        t.json "settings"
       end
     end
   end
@@ -30,18 +30,18 @@ class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
   def test_column
     column = JsonDataType.columns_hash["payload"]
     assert_equal :json, column.type
-    assert_equal 'json', column.sql_type
+    assert_equal "json", column.sql_type
 
     type = JsonDataType.type_for_attribute("payload")
     assert_not type.binary?
   end
 
   def test_change_table_supports_json
-    @connection.change_table('json_data_type') do |t|
-      t.json 'users'
+    @connection.change_table("json_data_type") do |t|
+      t.json "users"
     end
     JsonDataType.reset_column_information
-    column = JsonDataType.columns_hash['users']
+    column = JsonDataType.columns_hash["users"]
     assert_equal :json, column.type
   end
 
@@ -63,31 +63,31 @@ class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
 
     data = "{\"a_key\":\"a_value\"}"
     hash = type.deserialize(data)
-    assert_equal({'a_key' => 'a_value'}, hash)
-    assert_equal({'a_key' => 'a_value'}, type.deserialize(data))
+    assert_equal({"a_key" => "a_value"}, hash)
+    assert_equal({"a_key" => "a_value"}, type.deserialize(data))
 
     assert_equal({}, type.deserialize("{}"))
-    assert_equal({'key'=>nil}, type.deserialize('{"key": null}'))
-    assert_equal({'c'=>'}','"a"'=>'b "a b'}, type.deserialize(%q({"c":"}", "\"a\"":"b \"a b"})))
+    assert_equal({"key"=>nil}, type.deserialize('{"key": null}'))
+    assert_equal({"c"=>"}",'"a"'=>'b "a b'}, type.deserialize(%q({"c":"}", "\"a\"":"b \"a b"})))
   end
 
   def test_rewrite
     @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
     x = JsonDataType.first
-    x.payload = { '"a\'' => 'b' }
+    x.payload = { '"a\'' => "b" }
     assert x.save!
   end
 
   def test_select
     @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
     x = JsonDataType.first
-    assert_equal({'k' => 'v'}, x.payload)
+    assert_equal({"k" => "v"}, x.payload)
   end
 
   def test_select_multikey
     @connection.execute %q|insert into json_data_type (payload) VALUES ('{"k1":"v1", "k2":"v2", "k3":[1,2,3]}')|
     x = JsonDataType.first
-    assert_equal({'k1' => 'v1', 'k2' => 'v2', 'k3' => [1,2,3]}, x.payload)
+    assert_equal({"k1" => "v1", "k2" => "v2", "k3" => [1,2,3]}, x.payload)
   end
 
   def test_null_json
@@ -99,13 +99,13 @@ class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
   def test_select_array_json_value
     @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
     x = JsonDataType.first
-    assert_equal(['v0', {'k1' => 'v1'}], x.payload)
+    assert_equal(["v0", {"k1" => "v1"}], x.payload)
   end
 
   def test_rewrite_array_json_value
     @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
     x = JsonDataType.first
-    x.payload = ['v1', {'k2' => 'v2'}, 'v3']
+    x.payload = ["v1", {"k2" => "v2"}, "v3"]
     assert x.save!
   end
 
@@ -144,20 +144,20 @@ class Mysql2JSONTest < ActiveRecord::Mysql2TestCase
     json = JsonDataType.new
     assert_not json.changed?
 
-    json.payload = { 'one' => 'two' }
+    json.payload = { "one" => "two" }
     assert json.changed?
     assert json.payload_changed?
 
     json.save!
     assert_not json.changed?
 
-    json.payload['three'] = 'four'
+    json.payload["three"] = "four"
     assert json.payload_changed?
 
     json.save!
     json.reload
 
-    assert_equal({ 'one' => 'two', 'three' => 'four' }, json.payload)
+    assert_equal({ "one" => "two", "three" => "four" }, json.payload)
     assert_not json.changed?
   end
 
diff --git a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
index 61dd0828d0..ac74b7f80f 100644
--- a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
@@ -11,15 +11,15 @@ class Mysql2AdapterTest < ActiveRecord::Mysql2TestCase
   def test_exec_query_nothing_raises_with_no_result_queries
     assert_nothing_raised do
       with_example_table do
-        @conn.exec_query('INSERT INTO ex (number) VALUES (1)')
-        @conn.exec_query('DELETE FROM ex WHERE number = 1')
+        @conn.exec_query("INSERT INTO ex (number) VALUES (1)")
+        @conn.exec_query("DELETE FROM ex WHERE number = 1")
       end
     end
   end
 
   def test_valid_column
     with_example_table do
-      column = @conn.columns('ex').find { |col| col.name == 'id' }
+      column = @conn.columns("ex").find { |col| col.name == "id" }
       assert @conn.valid_type?(column.type)
     end
   end
@@ -45,8 +45,8 @@ class Mysql2AdapterTest < ActiveRecord::Mysql2TestCase
 
   def test_columns_for_distinct_with_case
     assert_equal(
-      'posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0',
-      @conn.columns_for_distinct('posts.id',
+      "posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0",
+      @conn.columns_for_distinct("posts.id",
         ["CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END"])
     )
   end
@@ -67,7 +67,7 @@ class Mysql2AdapterTest < ActiveRecord::Mysql2TestCase
 
   private
 
-  def with_example_table(definition = 'id int auto_increment primary key, number int, data varchar(255)', &block)
-    super(@conn, 'ex', definition, &block)
+  def with_example_table(definition = "id int auto_increment primary key, number int, data varchar(255)", &block)
+    super(@conn, "ex", definition, &block)
   end
 end
diff --git a/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb b/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
index ffb4e2c5cf..28df7fab98 100644
--- a/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/reserved_word_test.rb
@@ -4,22 +4,22 @@ require "cases/helper"
 # reserved word names (ie: group, order, values, etc...)
 class Mysql2ReservedWordTest < ActiveRecord::Mysql2TestCase
   class Group < ActiveRecord::Base
-    Group.table_name = 'group'
+    Group.table_name = "group"
     belongs_to :select
     has_one :values
   end
 
   class Select < ActiveRecord::Base
-    Select.table_name = 'select'
+    Select.table_name = "select"
     has_many :groups
   end
 
   class Values < ActiveRecord::Base
-    Values.table_name = 'values'
+    Values.table_name = "values"
   end
 
   class Distinct < ActiveRecord::Base
-    Distinct.table_name = 'distinct'
+    Distinct.table_name = "distinct"
     has_and_belongs_to_many :selects
     has_many :values, :through => :groups
   end
@@ -30,15 +30,15 @@ class Mysql2ReservedWordTest < ActiveRecord::Mysql2TestCase
     # we call execute directly here (and do similar below) because ActiveRecord::Base#create_table()
     # will fail with these table names if these test cases fail
 
-    create_tables_directly 'group'=>'id int auto_increment primary key, `order` varchar(255), select_id int',
-      'select'=>'id int auto_increment primary key',
-      'values'=>'id int auto_increment primary key, group_id int',
-      'distinct'=>'id int auto_increment primary key',
-      'distinct_select'=>'distinct_id int, select_id int'
+    create_tables_directly "group"=>"id int auto_increment primary key, `order` varchar(255), select_id int",
+      "select"=>"id int auto_increment primary key",
+      "values"=>"id int auto_increment primary key, group_id int",
+      "distinct"=>"id int auto_increment primary key",
+      "distinct_select"=>"distinct_id int, select_id int"
   end
 
   teardown do
-    drop_tables_directly ['group', 'select', 'values', 'distinct', 'distinct_select', 'order']
+    drop_tables_directly ["group", "select", "values", "distinct", "distinct_select", "order"]
   end
 
   # create tables with reserved-word names and columns
@@ -57,9 +57,9 @@ class Mysql2ReservedWordTest < ActiveRecord::Mysql2TestCase
 
   # alter column with a reserved-word name in a table with a reserved-word name
   def test_change_columns
-    assert_nothing_raised { @connection.change_column_default(:group, :order, 'whatever') }
+    assert_nothing_raised { @connection.change_column_default(:group, :order, "whatever") }
     #the quoting here will reveal any double quoting issues in change_column's interaction with the column method in the adapter
-    assert_nothing_raised { @connection.change_column('group', 'order', :Int, :default => 0) }
+    assert_nothing_raised { @connection.change_column("group", "order", :Int, :default => 0) }
     assert_nothing_raised { @connection.rename_column(:group, :order, :values) }
   end
 
@@ -78,11 +78,11 @@ class Mysql2ReservedWordTest < ActiveRecord::Mysql2TestCase
     create_test_fixtures :select, :distinct, :group, :values, :distinct_select
     x = nil
     assert_nothing_raised { x = Group.new }
-    x.order = 'x'
+    x.order = "x"
     assert_nothing_raised { x.save }
-    x.order = 'y'
+    x.order = "y"
     assert_nothing_raised { x.save }
-    assert_nothing_raised { Group.find_by_order('y') }
+    assert_nothing_raised { Group.find_by_order("y") }
     assert_nothing_raised { Group.find(1) }
   end
 
diff --git a/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb b/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
index 7c89fda582..cdd8f06801 100644
--- a/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb
@@ -18,7 +18,7 @@ class SchemaMigrationsTest < ActiveRecord::Mysql2TestCase
 
       connection.initialize_schema_migrations_table
 
-      assert connection.column_exists?(table_name, :version, :string, collation: 'utf8_general_ci')
+      assert connection.column_exists?(table_name, :version, :string, collation: "utf8_general_ci")
     end
   end
 
@@ -29,7 +29,7 @@ class SchemaMigrationsTest < ActiveRecord::Mysql2TestCase
 
       connection.initialize_internal_metadata_table
 
-      assert connection.column_exists?(table_name, :key, :string, collation: 'utf8_general_ci')
+      assert connection.column_exists?(table_name, :key, :string, collation: "utf8_general_ci")
     end
   end
 
diff --git a/activerecord/test/cases/adapters/mysql2/schema_test.rb b/activerecord/test/cases/adapters/mysql2/schema_test.rb
index 57ea8258d1..3c08a4ed1f 100644
--- a/activerecord/test/cases/adapters/mysql2/schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/schema_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'models/post'
-require 'models/comment'
+require "models/post"
+require "models/comment"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -16,7 +16,7 @@ module ActiveRecord
         @omgpost = Class.new(ActiveRecord::Base) do
           self.inheritance_column = :disabled
           self.table_name = "#{db}.#{table}"
-          def self.name; 'Post'; end
+          def self.name; "Post"; end
         end
       end
 
@@ -31,13 +31,13 @@ module ActiveRecord
           t.float :float_25, limit: 25
         end
 
-        column_no_limit = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_no_limit' }
-        column_short = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_short' }
-        column_long = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_long' }
+        column_no_limit = @connection.columns(:mysql_doubles).find { |c| c.name == "float_no_limit" }
+        column_short = @connection.columns(:mysql_doubles).find { |c| c.name == "float_short" }
+        column_long = @connection.columns(:mysql_doubles).find { |c| c.name == "float_long" }
 
-        column_23 = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_23' }
-        column_24 = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_24' }
-        column_25 = @connection.columns(:mysql_doubles).find { |c| c.name == 'float_25' }
+        column_23 = @connection.columns(:mysql_doubles).find { |c| c.name == "float_23" }
+        column_24 = @connection.columns(:mysql_doubles).find { |c| c.name == "float_24" }
+        column_25 = @connection.columns(:mysql_doubles).find { |c| c.name == "float_25" }
 
         # Mysql floats are precision 0..24, Mysql doubles are precision 25..53
         assert_equal 24, column_no_limit.limit
@@ -56,7 +56,7 @@ module ActiveRecord
       end
 
       def test_primary_key
-        assert_equal 'id', @omgpost.primary_key
+        assert_equal "id", @omgpost.primary_key
       end
 
       def test_data_source_exists?
@@ -69,11 +69,11 @@ module ActiveRecord
       end
 
       def test_dump_indexes
-        index_a_name = 'index_key_tests_on_snack'
-        index_b_name = 'index_key_tests_on_pizza'
-        index_c_name = 'index_key_tests_on_awesome'
+        index_a_name = "index_key_tests_on_snack"
+        index_b_name = "index_key_tests_on_pizza"
+        index_c_name = "index_key_tests_on_awesome"
 
-        table = 'key_tests'
+        table = "key_tests"
 
         indexes = @connection.indexes(table).sort_by(&:name)
         assert_equal 3,indexes.size
diff --git a/activerecord/test/cases/adapters/mysql2/sp_test.rb b/activerecord/test/cases/adapters/mysql2/sp_test.rb
index 4197ba45f1..4182532535 100644
--- a/activerecord/test/cases/adapters/mysql2/sp_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/sp_test.rb
@@ -1,13 +1,13 @@
 require "cases/helper"
-require 'models/topic'
-require 'models/reply'
+require "models/topic"
+require "models/reply"
 
 class Mysql2StoredProcedureTest < ActiveRecord::Mysql2TestCase
   fixtures :topics
 
   def setup
     @connection = ActiveRecord::Base.connection
-    unless ActiveRecord::Base.connection.version >= '5.6.0'
+    unless ActiveRecord::Base.connection.version >= "5.6.0"
       skip("no stored procedure support")
     end
   end
@@ -17,19 +17,19 @@ class Mysql2StoredProcedureTest < ActiveRecord::Mysql2TestCase
   # In MySQL 5.6, CLIENT_MULTI_RESULTS is enabled by default.
   # http://dev.mysql.com/doc/refman/5.6/en/call.html
   def test_multi_results
-    rows = @connection.select_rows('CALL ten();')
+    rows = @connection.select_rows("CALL ten();")
     assert_equal 10, rows[0][0].to_i, "ten() did not return 10 as expected: #{rows.inspect}"
     assert @connection.active?, "Bad connection use by 'Mysql2Adapter.select_rows'"
   end
 
   def test_multi_results_from_select_one
-    row = @connection.select_one('CALL topics(1);')
-    assert_equal 'David', row['author_name']
+    row = @connection.select_one("CALL topics(1);")
+    assert_equal "David", row["author_name"]
     assert @connection.active?, "Bad connection use by 'Mysql2Adapter.select_one'"
   end
 
   def test_multi_results_from_find_by_sql
-    topics = Topic.find_by_sql 'CALL topics(3);'
+    topics = Topic.find_by_sql "CALL topics(3);"
     assert_equal 3, topics.size
     assert @connection.active?, "Bad connection use by 'Mysql2Adapter.select'"
   end
diff --git a/activerecord/test/cases/adapters/mysql2/sql_types_test.rb b/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
index 4926bc2267..bee42d48f1 100644
--- a/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/sql_types_test.rb
@@ -2,10 +2,10 @@ require "cases/helper"
 
 class Mysql2SqlTypesTest < ActiveRecord::Mysql2TestCase
   def test_binary_types
-    assert_equal 'varbinary(64)', type_to_sql(:binary, 64)
-    assert_equal 'varbinary(4095)', type_to_sql(:binary, 4095)
-    assert_equal 'blob', type_to_sql(:binary, 4096)
-    assert_equal 'blob', type_to_sql(:binary)
+    assert_equal "varbinary(64)", type_to_sql(:binary, 64)
+    assert_equal "varbinary(4095)", type_to_sql(:binary, 4095)
+    assert_equal "blob", type_to_sql(:binary, 4096)
+    assert_equal "blob", type_to_sql(:binary)
   end
 
   def type_to_sql(*args)
diff --git a/activerecord/test/cases/adapters/mysql2/table_options_test.rb b/activerecord/test/cases/adapters/mysql2/table_options_test.rb
index af121ee7d9..61a8ce9bc0 100644
--- a/activerecord/test/cases/adapters/mysql2/table_options_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/table_options_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class Mysql2TableOptionsTest < ActiveRecord::Mysql2TestCase
   include SchemaDumpingHelper
diff --git a/activerecord/test/cases/adapters/mysql2/transaction_test.rb b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
index 5d8765d63a..edd5353ee3 100644
--- a/activerecord/test/cases/adapters/mysql2/transaction_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
@@ -1,12 +1,12 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 module ActiveRecord
   class Mysql2TransactionTest < ActiveRecord::Mysql2TestCase
     self.use_transactional_tests = false
 
     class Sample < ActiveRecord::Base
-      self.table_name = 'samples'
+      self.table_name = "samples"
     end
 
     setup do
@@ -14,9 +14,9 @@ module ActiveRecord
       @connection.clear_cache!
 
       @connection.transaction do
-        @connection.drop_table 'samples', if_exists: true
-        @connection.create_table('samples') do |t|
-          t.integer 'value'
+        @connection.drop_table "samples", if_exists: true
+        @connection.create_table("samples") do |t|
+          t.integer "value"
         end
       end
 
@@ -24,7 +24,7 @@ module ActiveRecord
     end
 
     teardown do
-      @connection.drop_table 'samples', if_exists: true
+      @connection.drop_table "samples", if_exists: true
     end
 
     test "raises Deadlocked when a deadlock is encountered" do
diff --git a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
index 439e2ce6f7..3d805bdbdc 100644
--- a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
@@ -1,4 +1,4 @@
-require 'cases/helper'
+require "cases/helper"
 
 class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
   def setup
@@ -16,7 +16,7 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
   def test_create_database_with_encoding
     assert_equal %(CREATE DATABASE "matt" ENCODING = 'utf8'), create_database(:matt)
     assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'latin1'), create_database(:aimonetti, :encoding => :latin1)
-    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'latin1'), create_database(:aimonetti, 'encoding' => :latin1)
+    assert_equal %(CREATE DATABASE "aimonetti" ENCODING = 'latin1'), create_database(:aimonetti, "encoding" => :latin1)
   end
 
   def test_create_database_with_collation_and_ctype
@@ -31,10 +31,10 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
     assert_equal expected, add_index(:people, :last_name, unique: true, where: "state = 'active'")
 
     expected = %(CREATE UNIQUE INDEX  "index_people_on_lower_last_name" ON "people"  (lower(last_name)))
-    assert_equal expected, add_index(:people, 'lower(last_name)', unique: true)
+    assert_equal expected, add_index(:people, "lower(last_name)", unique: true)
 
     expected = %(CREATE UNIQUE INDEX  "index_people_on_last_name_varchar_pattern_ops" ON "people"  (last_name varchar_pattern_ops))
-    assert_equal expected, add_index(:people, 'last_name varchar_pattern_ops', unique: true)
+    assert_equal expected, add_index(:people, "last_name varchar_pattern_ops", unique: true)
 
     expected = %(CREATE  INDEX CONCURRENTLY "index_people_on_last_name" ON "people"  ("last_name"))
     assert_equal expected, add_index(:people, :last_name, algorithm: :concurrently)
@@ -50,7 +50,7 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
       assert_equal expected, add_index(:people, :last_name, using: type, unique: true, where: "state = 'active'")
 
       expected = %(CREATE UNIQUE INDEX  "index_people_on_lower_last_name" ON "people" USING #{type} (lower(last_name)))
-      assert_equal expected, add_index(:people, 'lower(last_name)', using: type, unique: true)
+      assert_equal expected, add_index(:people, "lower(last_name)", using: type, unique: true)
     end
 
     assert_raise ArgumentError do
@@ -63,7 +63,7 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
   def test_remove_index
     # remove_index calls index_name_for_remove which can't work since execute is stubbed
     ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.send(:define_method, :index_name_for_remove) do |*|
-      'index_people_on_last_name'
+      "index_people_on_last_name"
     end
 
     expected = %(DROP INDEX CONCURRENTLY "index_people_on_last_name")
diff --git a/activerecord/test/cases/adapters/postgresql/array_test.rb b/activerecord/test/cases/adapters/postgresql/array_test.rb
index 70792e937c..a26547b8f1 100644
--- a/activerecord/test/cases/adapters/postgresql/array_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/array_test.rb
@@ -1,35 +1,35 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
   include InTimeZone
 
   class PgArray < ActiveRecord::Base
-    self.table_name = 'pg_arrays'
+    self.table_name = "pg_arrays"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
 
-    enable_extension!('hstore', @connection)
+    enable_extension!("hstore", @connection)
 
     @connection.transaction do
-      @connection.create_table('pg_arrays') do |t|
-        t.string 'tags', array: true
-        t.integer 'ratings', array: true
+      @connection.create_table("pg_arrays") do |t|
+        t.string "tags", array: true
+        t.integer "ratings", array: true
         t.datetime :datetimes, array: true
         t.hstore :hstores, array: true
       end
     end
     PgArray.reset_column_information
-    @column = PgArray.columns_hash['tags']
+    @column = PgArray.columns_hash["tags"]
     @type = PgArray.type_for_attribute("tags")
   end
 
   teardown do
-    @connection.drop_table 'pg_arrays', if_exists: true
-    disable_extension!('hstore', @connection)
+    @connection.drop_table "pg_arrays", if_exists: true
+    disable_extension!("hstore", @connection)
   end
 
   def test_column
@@ -38,26 +38,26 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     assert @column.array?
     assert_not @type.binary?
 
-    ratings_column = PgArray.columns_hash['ratings']
+    ratings_column = PgArray.columns_hash["ratings"]
     assert_equal :integer, ratings_column.type
     assert ratings_column.array?
   end
 
   def test_default
-    @connection.add_column 'pg_arrays', 'score', :integer, array: true, default: [4, 4, 2]
+    @connection.add_column "pg_arrays", "score", :integer, array: true, default: [4, 4, 2]
     PgArray.reset_column_information
 
-    assert_equal([4, 4, 2], PgArray.column_defaults['score'])
+    assert_equal([4, 4, 2], PgArray.column_defaults["score"])
     assert_equal([4, 4, 2], PgArray.new.score)
   ensure
     PgArray.reset_column_information
   end
 
   def test_default_strings
-    @connection.add_column 'pg_arrays', 'names', :string, array: true, default: ["foo", "bar"]
+    @connection.add_column "pg_arrays", "names", :string, array: true, default: ["foo", "bar"]
     PgArray.reset_column_information
 
-    assert_equal(["foo", "bar"], PgArray.column_defaults['names'])
+    assert_equal(["foo", "bar"], PgArray.column_defaults["names"])
     assert_equal(["foo", "bar"], PgArray.new.names)
   ensure
     PgArray.reset_column_information
@@ -68,10 +68,10 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     @connection.change_column :pg_arrays, :snippets, :text, array: true, default: []
 
     PgArray.reset_column_information
-    column = PgArray.columns_hash['snippets']
+    column = PgArray.columns_hash["snippets"]
 
     assert_equal :text, column.type
-    assert_equal [], PgArray.column_defaults['snippets']
+    assert_equal [], PgArray.column_defaults["snippets"]
     assert column.array?
   end
 
@@ -88,17 +88,17 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     @connection.change_column_default :pg_arrays, :tags, []
 
     PgArray.reset_column_information
-    assert_equal [], PgArray.column_defaults['tags']
+    assert_equal [], PgArray.column_defaults["tags"]
   end
 
   def test_type_cast_array
-    assert_equal(['1', '2', '3'], @type.deserialize('{1,2,3}'))
-    assert_equal([], @type.deserialize('{}'))
-    assert_equal([nil], @type.deserialize('{NULL}'))
+    assert_equal(["1", "2", "3"], @type.deserialize("{1,2,3}"))
+    assert_equal([], @type.deserialize("{}"))
+    assert_equal([nil], @type.deserialize("{NULL}"))
   end
 
   def test_type_cast_integers
-    x = PgArray.new(ratings: ['1', '2'])
+    x = PgArray.new(ratings: ["1", "2"])
 
     assert_equal([1, 2], x.ratings)
 
@@ -117,15 +117,15 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   def test_select_with_strings
     @connection.execute "insert into pg_arrays (tags) VALUES ('{1,2,3}')"
     x = PgArray.first
-    assert_equal(['1','2','3'], x.tags)
+    assert_equal(["1","2","3"], x.tags)
   end
 
   def test_rewrite_with_strings
     @connection.execute "insert into pg_arrays (tags) VALUES ('{1,2,3}')"
     x = PgArray.first
-    x.tags = ['1','2','3','4']
+    x.tags = ["1","2","3","4"]
     x.save!
-    assert_equal ['1','2','3','4'], x.reload.tags
+    assert_equal ["1","2","3","4"], x.reload.tags
   end
 
   def test_select_with_integers
@@ -137,25 +137,25 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   def test_rewrite_with_integers
     @connection.execute "insert into pg_arrays (ratings) VALUES ('{1,2,3}')"
     x = PgArray.first
-    x.ratings = [2, '3', 4]
+    x.ratings = [2, "3", 4]
     x.save!
     assert_equal [2, 3, 4], x.reload.ratings
   end
 
   def test_multi_dimensional_with_strings
-    assert_cycle(:tags, [[['1'], ['2']], [['2'], ['3']]])
+    assert_cycle(:tags, [[["1"], ["2"]], [["2"], ["3"]]])
   end
 
   def test_with_empty_strings
-    assert_cycle(:tags, [ '1', '2', '', '4', '', '5' ])
+    assert_cycle(:tags, [ "1", "2", "", "4", "", "5" ])
   end
 
   def test_with_multi_dimensional_empty_strings
-    assert_cycle(:tags, [[['1', '2'], ['', '4'], ['', '5']]])
+    assert_cycle(:tags, [[["1", "2"], ["", "4"], ["", "5"]]])
   end
 
   def test_with_arbitrary_whitespace
-    assert_cycle(:tags, [[['1', '2'], ['    ', '4'], ['    ', '5']]])
+    assert_cycle(:tags, [[["1", "2"], ["    ", "4"], ["    ", "5"]]])
   end
 
   def test_multi_dimensional_with_integers
@@ -163,23 +163,23 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_strings_with_quotes
-    assert_cycle(:tags, ['this has','some "s that need to be escaped"'])
+    assert_cycle(:tags, ["this has",'some "s that need to be escaped"'])
   end
 
   def test_strings_with_commas
-    assert_cycle(:tags, ['this,has','many,values'])
+    assert_cycle(:tags, ["this,has","many,values"])
   end
 
   def test_strings_with_array_delimiters
-    assert_cycle(:tags, ['{','}'])
+    assert_cycle(:tags, ["{","}"])
   end
 
   def test_strings_with_null_strings
-    assert_cycle(:tags, ['NULL','NULL'])
+    assert_cycle(:tags, ["NULL","NULL"])
   end
 
   def test_contains_nils
-    assert_cycle(:tags, ['1',nil,nil])
+    assert_cycle(:tags, ["1",nil,nil])
   end
 
   def test_insert_fixture
@@ -211,14 +211,14 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
     x = PgArray.create!(tags: tags)
     x.reload
 
-    assert_equal x.tags_before_type_cast, PgArray.type_for_attribute('tags').serialize(tags)
+    assert_equal x.tags_before_type_cast, PgArray.type_for_attribute("tags").serialize(tags)
   end
 
   def test_quoting_non_standard_delimiters
     strings = ["hello,", "world;"]
     oid = ActiveRecord::ConnectionAdapters::PostgreSQL::OID
-    comma_delim = oid::Array.new(ActiveRecord::Type::String.new, ',')
-    semicolon_delim = oid::Array.new(ActiveRecord::Type::String.new, ';')
+    comma_delim = oid::Array.new(ActiveRecord::Type::String.new, ",")
+    semicolon_delim = oid::Array.new(ActiveRecord::Type::String.new, ";")
 
     assert_equal %({"hello,",world;}), comma_delim.serialize(strings)
     assert_equal %({hello,;"world;"}), semicolon_delim.serialize(strings)
@@ -236,13 +236,13 @@ class PostgresqlArrayTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_mutate_value_in_array
-    x = PgArray.create!(hstores: [{ a: 'a' }, { b: 'b' }])
+    x = PgArray.create!(hstores: [{ a: "a" }, { b: "b" }])
 
-    x.hstores.first['a'] = 'c'
+    x.hstores.first["a"] = "c"
     x.save!
     x.reload
 
-    assert_equal [{ 'a' => 'c' }, { 'b' => 'b' }], x.hstores
+    assert_equal [{ "a" => "c" }, { "b" => "b" }], x.hstores
     assert_not x.changed?
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
index cec6081aec..7f36a6b457 100644
--- a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'support/connection_helper'
-require 'support/schema_dumping_helper'
+require "support/connection_helper"
+require "support/schema_dumping_helper"
 
 class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -10,7 +10,7 @@ class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
 
   def setup
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_bit_strings', :force => true) do |t|
+    @connection.create_table("postgresql_bit_strings", :force => true) do |t|
       t.bit :a_bit, default: "00000011", limit: 8
       t.bit_varying :a_bit_varying, default: "0011", limit: 4
       t.bit :another_bit
@@ -20,7 +20,7 @@ class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
 
   def teardown
     return unless @connection
-    @connection.drop_table 'postgresql_bit_strings', if_exists: true
+    @connection.drop_table "postgresql_bit_strings", if_exists: true
   end
 
   def test_bit_string_column
@@ -44,10 +44,10 @@ class PostgresqlBitStringTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_default
-    assert_equal "00000011", PostgresqlBitString.column_defaults['a_bit']
+    assert_equal "00000011", PostgresqlBitString.column_defaults["a_bit"]
     assert_equal "00000011", PostgresqlBitString.new.a_bit
 
-    assert_equal "0011", PostgresqlBitString.column_defaults['a_bit_varying']
+    assert_equal "0011", PostgresqlBitString.column_defaults["a_bit_varying"]
     assert_equal "0011", PostgresqlBitString.new.a_bit_varying
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/bytea_test.rb b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
index 7adc070430..dc0df8715a 100644
--- a/activerecord/test/cases/adapters/postgresql/bytea_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bytea_test.rb
@@ -1,29 +1,29 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
 
   class ByteaDataType < ActiveRecord::Base
-    self.table_name = 'bytea_data_type'
+    self.table_name = "bytea_data_type"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
     begin
       @connection.transaction do
-        @connection.create_table('bytea_data_type') do |t|
-          t.binary 'payload'
-          t.binary 'serialized'
+        @connection.create_table("bytea_data_type") do |t|
+          t.binary "payload"
+          t.binary "serialized"
         end
       end
     end
-    @column = ByteaDataType.columns_hash['payload']
+    @column = ByteaDataType.columns_hash["payload"]
     @type = ByteaDataType.type_for_attribute("payload")
   end
 
   teardown do
-    @connection.drop_table 'bytea_data_type', if_exists: true
+    @connection.drop_table "bytea_data_type", if_exists: true
   end
 
   def test_column
@@ -32,7 +32,7 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_binary_columns_are_limitless_the_upper_limit_is_one_GB
-    assert_equal 'bytea', @connection.type_to_sql(:binary, 100_000)
+    assert_equal "bytea", @connection.type_to_sql(:binary, 100_000)
     assert_raise ActiveRecord::ActiveRecordError do
       @connection.type_to_sql :binary, 4294967295
     end
@@ -42,8 +42,8 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
     assert @column
 
     data = "\u001F\x8B"
-    assert_equal('UTF-8', data.encoding.name)
-    assert_equal('ASCII-8BIT', @type.deserialize(data).encoding.name)
+    assert_equal("UTF-8", data.encoding.name)
+    assert_equal("ASCII-8BIT", @type.deserialize(data).encoding.name)
   end
 
   def test_type_cast_binary_value
@@ -88,14 +88,14 @@ class PostgresqlByteaTest < ActiveRecord::PostgreSQLTestCase
   def test_via_to_sql_with_complicating_connection
     Thread.new do
       other_conn = ActiveRecord::Base.connection
-      other_conn.execute('SET standard_conforming_strings = off')
+      other_conn.execute("SET standard_conforming_strings = off")
     end.join
 
     test_via_to_sql
   end
 
   def test_write_binary
-    data = File.read(File.join(File.dirname(__FILE__), '..', '..', '..', 'assets', 'example.log'))
+    data = File.read(File.join(File.dirname(__FILE__), "..", "..", "..", "assets", "example.log"))
     assert(data.size > 1)
     record = ByteaDataType.create(payload: data)
     assert_not record.new_record?
diff --git a/activerecord/test/cases/adapters/postgresql/change_schema_test.rb b/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
index bc12df668d..ea642069d2 100644
--- a/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/change_schema_test.rb
@@ -1,4 +1,4 @@
-require 'cases/helper'
+require "cases/helper"
 
 module ActiveRecord
   class Migration
@@ -19,17 +19,17 @@ module ActiveRecord
 
       def test_change_string_to_date
         connection.change_column :strings, :somedate, :timestamp, using: 'CAST("somedate" AS timestamp)'
-        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == 'somedate' }.type
+        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == "somedate" }.type
       end
 
       def test_change_type_with_symbol
         connection.change_column :strings, :somedate, :timestamp, cast_as: :timestamp
-        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == 'somedate' }.type
+        assert_equal :datetime, connection.columns(:strings).find { |c| c.name == "somedate" }.type
       end
 
       def test_change_type_with_array
         connection.change_column :strings, :somedate, :timestamp, array: true, cast_as: :timestamp
-        column = connection.columns(:strings).find { |c| c.name == 'somedate' }
+        column = connection.columns(:strings).find { |c| c.name == "somedate" }
         assert_equal :datetime, column.type
         assert column.array?
       end
diff --git a/activerecord/test/cases/adapters/postgresql/citext_test.rb b/activerecord/test/cases/adapters/postgresql/citext_test.rb
index bd62041e79..ca95e4b626 100644
--- a/activerecord/test/cases/adapters/postgresql/citext_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/citext_test.rb
@@ -1,49 +1,49 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+require "cases/helper"
+require "support/schema_dumping_helper"
 
 if ActiveRecord::Base.connection.supports_extensions?
   class PostgresqlCitextTest < ActiveRecord::PostgreSQLTestCase
     include SchemaDumpingHelper
     class Citext < ActiveRecord::Base
-      self.table_name = 'citexts'
+      self.table_name = "citexts"
     end
 
     def setup
       @connection = ActiveRecord::Base.connection
 
-      enable_extension!('citext', @connection)
+      enable_extension!("citext", @connection)
 
-      @connection.create_table('citexts') do |t|
-        t.citext 'cival'
+      @connection.create_table("citexts") do |t|
+        t.citext "cival"
       end
     end
 
     teardown do
-      @connection.drop_table 'citexts', if_exists: true
-      disable_extension!('citext', @connection)
+      @connection.drop_table "citexts", if_exists: true
+      disable_extension!("citext", @connection)
     end
 
     def test_citext_enabled
-      assert @connection.extension_enabled?('citext')
+      assert @connection.extension_enabled?("citext")
     end
 
     def test_column
-      column = Citext.columns_hash['cival']
+      column = Citext.columns_hash["cival"]
       assert_equal :citext, column.type
-      assert_equal 'citext', column.sql_type
+      assert_equal "citext", column.sql_type
       assert_not column.array?
 
-      type = Citext.type_for_attribute('cival')
+      type = Citext.type_for_attribute("cival")
       assert_not type.binary?
     end
 
     def test_change_table_supports_json
       @connection.transaction do
-        @connection.change_table('citexts') do |t|
-          t.citext 'username'
+        @connection.change_table("citexts") do |t|
+          t.citext "username"
         end
         Citext.reset_column_information
-        column = Citext.columns_hash['username']
+        column = Citext.columns_hash["username"]
         assert_equal :citext, column.type
 
         raise ActiveRecord::Rollback # reset the schema change
@@ -53,7 +53,7 @@ if ActiveRecord::Base.connection.supports_extensions?
     end
 
     def test_write
-      x = Citext.new(cival: 'Some CI Text')
+      x = Citext.new(cival: "Some CI Text")
       x.save!
       citext = Citext.first
       assert_equal "Some CI Text", citext.cival
@@ -66,8 +66,8 @@ if ActiveRecord::Base.connection.supports_extensions?
 
     def test_select_case_insensitive
       @connection.execute "insert into citexts (cival) values('Cased Text')"
-      x = Citext.where(cival: 'cased text').first
-      assert_equal 'Cased Text', x.cival
+      x = Citext.where(cival: "cased text").first
+      assert_equal "Cased Text", x.cival
     end
 
     def test_schema_dump_with_shorthand
diff --git a/activerecord/test/cases/adapters/postgresql/collation_test.rb b/activerecord/test/cases/adapters/postgresql/collation_test.rb
index 8470329c35..b39e298a5d 100644
--- a/activerecord/test/cases/adapters/postgresql/collation_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/collation_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlCollationTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -7,8 +7,8 @@ class PostgresqlCollationTest < ActiveRecord::PostgreSQLTestCase
   def setup
     @connection = ActiveRecord::Base.connection
     @connection.create_table :postgresql_collations, force: true do |t|
-      t.string :string_c, collation: 'C'
-      t.text :text_posix, collation: 'POSIX'
+      t.string :string_c, collation: "C"
+      t.text :text_posix, collation: "POSIX"
     end
   end
 
@@ -17,32 +17,32 @@ class PostgresqlCollationTest < ActiveRecord::PostgreSQLTestCase
   end
 
   test "string column with collation" do
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'string_c' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "string_c" }
     assert_equal :string, column.type
-    assert_equal 'C', column.collation
+    assert_equal "C", column.collation
   end
 
   test "text column with collation" do
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'text_posix' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "text_posix" }
     assert_equal :text, column.type
-    assert_equal 'POSIX', column.collation
+    assert_equal "POSIX", column.collation
   end
 
   test "add column with collation" do
-    @connection.add_column :postgresql_collations, :title, :string, collation: 'C'
+    @connection.add_column :postgresql_collations, :title, :string, collation: "C"
 
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'title' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "title" }
     assert_equal :string, column.type
-    assert_equal 'C', column.collation
+    assert_equal "C", column.collation
   end
 
   test "change column with collation" do
     @connection.add_column :postgresql_collations, :description, :string
-    @connection.change_column :postgresql_collations, :description, :text, collation: 'POSIX'
+    @connection.change_column :postgresql_collations, :description, :text, collation: "POSIX"
 
-    column = @connection.columns(:postgresql_collations).find { |c| c.name == 'description' }
+    column = @connection.columns(:postgresql_collations).find { |c| c.name == "description" }
     assert_equal :text, column.type
-    assert_equal 'POSIX', column.collation
+    assert_equal "POSIX", column.collation
   end
 
   test "schema dump includes collation" do
diff --git a/activerecord/test/cases/adapters/postgresql/composite_test.rb b/activerecord/test/cases/adapters/postgresql/composite_test.rb
index 1de87e5f01..9377837810 100644
--- a/activerecord/test/cases/adapters/postgresql/composite_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/composite_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 module PostgresqlCompositeBehavior
   include ConnectionHelper
@@ -20,7 +20,7 @@ module PostgresqlCompositeBehavior
              street VARCHAR(90)
          );
         SQL
-      @connection.create_table('postgresql_composites') do |t|
+      @connection.create_table("postgresql_composites") do |t|
         t.column :address, :full_address
       end
     end
@@ -29,8 +29,8 @@ module PostgresqlCompositeBehavior
   def teardown
     super
 
-    @connection.drop_table 'postgresql_composites', if_exists: true
-    @connection.execute 'DROP TYPE IF EXISTS full_address'
+    @connection.drop_table "postgresql_composites", if_exists: true
+    @connection.execute "DROP TYPE IF EXISTS full_address"
     reset_connection
     PostgresqlComposite.reset_column_information
   end
@@ -126,7 +126,7 @@ class PostgresqlCompositeWithCustomOIDTest < ActiveRecord::PostgreSQLTestCase
     composite.address = FullAddress.new("Paris", "Rue Basse")
     composite.save!
 
-    assert_equal 'Paris', composite.reload.address.city
-    assert_equal 'Rue Basse', composite.reload.address.street
+    assert_equal "Paris", composite.reload.address.city
+    assert_equal "Rue Basse", composite.reload.address.street
   end
 end
diff --git a/activerecord/test/cases/adapters/postgresql/connection_test.rb b/activerecord/test/cases/adapters/postgresql/connection_test.rb
index f8403bfe1a..436ab3ffa1 100644
--- a/activerecord/test/cases/adapters/postgresql/connection_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/connection_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 module ActiveRecord
   class PostgresqlConnectionTest < ActiveRecord::PostgreSQLTestCase
@@ -13,7 +13,7 @@ module ActiveRecord
     def setup
       super
       @subscriber = SQLSubscriber.new
-      @subscription = ActiveSupport::Notifications.subscribe('sql.active_record', @subscriber)
+      @subscription = ActiveSupport::Notifications.subscribe("sql.active_record", @subscriber)
       @connection = ActiveRecord::Base.connection
     end
 
@@ -23,10 +23,10 @@ module ActiveRecord
     end
 
     def test_truncate
-      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first['count'].to_i
+      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first["count"].to_i
       assert_operator count, :>, 0
       ActiveRecord::Base.connection.truncate("comments")
-      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first['count'].to_i
+      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first["count"].to_i
       assert_equal 0, count
     end
 
@@ -54,85 +54,85 @@ module ActiveRecord
       NonExistentTable.establish_connection(params)
 
       # Verify the connection param has been applied.
-      expect = NonExistentTable.connection.query('show geqo').first.first
-      assert_equal 'off', expect
+      expect = NonExistentTable.connection.query("show geqo").first.first
+      assert_equal "off", expect
     end
 
     def test_reset
-      @connection.query('ROLLBACK')
-      @connection.query('SET geqo TO off')
+      @connection.query("ROLLBACK")
+      @connection.query("SET geqo TO off")
 
       # Verify the setting has been applied.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'off', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "off", expect
 
       @connection.reset!
 
       # Verify the setting has been cleared.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'on', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "on", expect
     end
 
     def test_reset_with_transaction
-      @connection.query('ROLLBACK')
-      @connection.query('SET geqo TO off')
+      @connection.query("ROLLBACK")
+      @connection.query("SET geqo TO off")
 
       # Verify the setting has been applied.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'off', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "off", expect
 
-      @connection.query('BEGIN')
+      @connection.query("BEGIN")
       @connection.reset!
 
       # Verify the setting has been cleared.
-      expect = @connection.query('show geqo').first.first
-      assert_equal 'on', expect
+      expect = @connection.query("show geqo").first.first
+      assert_equal "on", expect
     end
 
     def test_tables_logs_name
-      ActiveSupport::Deprecation.silence { @connection.tables('hello') }
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      ActiveSupport::Deprecation.silence { @connection.tables("hello") }
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_indexes_logs_name
-      @connection.indexes('items', 'hello')
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      @connection.indexes("items", "hello")
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_table_exists_logs_name
-      ActiveSupport::Deprecation.silence { @connection.table_exists?('items') }
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      ActiveSupport::Deprecation.silence { @connection.table_exists?("items") }
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_table_alias_length_logs_name
       @connection.instance_variable_set("@table_alias_length", nil)
       @connection.table_alias_length
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_current_database_logs_name
       @connection.current_database
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_encoding_logs_name
       @connection.encoding
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     def test_schema_names_logs_name
       @connection.schema_names
-      assert_equal 'SCHEMA', @subscriber.logged[0][1]
+      assert_equal "SCHEMA", @subscriber.logged[0][1]
     end
 
     if ActiveRecord::Base.connection.prepared_statements
       def test_statement_key_is_logged
         bind = Relation::QueryAttribute.new(nil, 1, Type::Value.new)
-        @connection.exec_query('SELECT $1::integer', 'SQL', [bind], prepare: true)
+        @connection.exec_query("SELECT $1::integer", "SQL", [bind], prepare: true)
         name = @subscriber.payloads.last[:statement_name]
         assert name
         res = @connection.exec_query("EXPLAIN (FORMAT JSON) EXECUTE #{name}(1)")
-        plan = res.column_types['QUERY PLAN'].deserialize res.rows.first.first
+        plan = res.column_types["QUERY PLAN"].deserialize res.rows.first.first
         assert_operator plan.length, :>, 0
       end
     end
@@ -146,7 +146,7 @@ module ActiveRecord
     # To restart PostgreSQL 9.1 on OS X, installed via MacPorts, ...
     # sudo su postgres -c "pg_ctl restart -D /opt/local/var/db/postgresql91/defaultdb/ -m fast"
     def test_reconnection_after_actual_disconnection_with_verify
-      original_connection_pid = @connection.query('select pg_backend_pid()')
+      original_connection_pid = @connection.query("select pg_backend_pid()")
 
       # Sanity check.
       assert @connection.active?
@@ -155,8 +155,8 @@ module ActiveRecord
         secondary_connection = ActiveRecord::Base.connection_pool.checkout
         secondary_connection.query("select pg_terminate_backend(#{original_connection_pid.first.first})")
         ActiveRecord::Base.connection_pool.checkin(secondary_connection)
-      elsif ARTest.config['with_manual_interventions']
-        puts 'Kill the connection now (e.g. by restarting the PostgreSQL ' +
+      elsif ARTest.config["with_manual_interventions"]
+        puts "Kill the connection now (e.g. by restarting the PostgreSQL " +
           'server with the "-m fast" option) and then press enter.'
         $stdin.gets
       else
@@ -172,7 +172,7 @@ module ActiveRecord
 
       # If we get no exception here, then either we re-connected successfully, or
       # we never actually got disconnected.
-      new_connection_pid = @connection.query('select pg_backend_pid()')
+      new_connection_pid = @connection.query("select pg_backend_pid()")
 
       assert_not_equal original_connection_pid, new_connection_pid,
         "umm -- looks like you didn't break the connection, because we're still " +
@@ -241,7 +241,7 @@ module ActiveRecord
       with_warning_suppression do
         released_non_existent_lock = @connection.release_advisory_lock(fake_lock_id)
         assert_equal released_non_existent_lock, false,
-          'expected release_advisory_lock to return false when there was no lock to release'
+          "expected release_advisory_lock to return false when there was no lock to release"
       end
     end
 
@@ -249,7 +249,7 @@ module ActiveRecord
 
     def with_warning_suppression
       log_level = @connection.client_min_messages
-      @connection.client_min_messages = 'error'
+      @connection.client_min_messages = "error"
       yield
       @connection.client_min_messages = log_level
     end
diff --git a/activerecord/test/cases/adapters/postgresql/datatype_test.rb b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
index 232c25cb3b..aa077b59a0 100644
--- a/activerecord/test/cases/adapters/postgresql/datatype_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/ddl_helper'
+require "support/ddl_helper"
 
 
 class PostgresqlTime < ActiveRecord::Base
@@ -38,8 +38,8 @@ class PostgresqlDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_time_values
-    assert_equal '-1 years -2 days', @first_time.time_interval
-    assert_equal '-21 days', @first_time.scaled_time_interval
+    assert_equal "-1 years -2 days", @first_time.time_interval
+    assert_equal "-21 days", @first_time.scaled_time_interval
   end
 
   def test_oid_values
@@ -47,10 +47,10 @@ class PostgresqlDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_update_time
-    @first_time.time_interval = '2 years 3 minutes'
+    @first_time.time_interval = "2 years 3 minutes"
     assert @first_time.save
     assert @first_time.reload
-    assert_equal '2 years 00:03:00', @first_time.time_interval
+    assert_equal "2 years 00:03:00", @first_time.time_interval
   end
 
   def test_update_oid
@@ -62,7 +62,7 @@ class PostgresqlDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_text_columns_are_limitless_the_upper_limit_is_one_GB
-    assert_equal 'text', @connection.type_to_sql(:text, 100_000)
+    assert_equal "text", @connection.type_to_sql(:text, 100_000)
     assert_raise ActiveRecord::ActiveRecordError do
       @connection.type_to_sql :text, 4294967295
     end
@@ -77,15 +77,15 @@ class PostgresqlInternalDataTypeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_name_column_type
-    with_example_table @connection, 'ex', 'data name' do
-      column = @connection.columns('ex').find { |col| col.name == 'data' }
+    with_example_table @connection, "ex", "data name" do
+      column = @connection.columns("ex").find { |col| col.name == "data" }
       assert_equal :string, column.type
     end
   end
 
   def test_char_column_type
-    with_example_table @connection, 'ex', 'data "char"' do
-      column = @connection.columns('ex').find { |col| col.name == 'data' }
+    with_example_table @connection, "ex", 'data "char"' do
+      column = @connection.columns("ex").find { |col| col.name == "data" }
       assert_equal :string, column.type
     end
   end
diff --git a/activerecord/test/cases/adapters/postgresql/domain_test.rb b/activerecord/test/cases/adapters/postgresql/domain_test.rb
index 6102ddacd1..f1eb8adb15 100644
--- a/activerecord/test/cases/adapters/postgresql/domain_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/domain_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class PostgresqlDomainTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -12,15 +12,15 @@ class PostgresqlDomainTest < ActiveRecord::PostgreSQLTestCase
     @connection = ActiveRecord::Base.connection
     @connection.transaction do
       @connection.execute "CREATE DOMAIN custom_money as numeric(8,2)"
-      @connection.create_table('postgresql_domains') do |t|
+      @connection.create_table("postgresql_domains") do |t|
         t.column :price, :custom_money
       end
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_domains', if_exists: true
-    @connection.execute 'DROP DOMAIN IF EXISTS custom_money'
+    @connection.drop_table "postgresql_domains", if_exists: true
+    @connection.execute "DROP DOMAIN IF EXISTS custom_money"
     reset_connection
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/enum_test.rb b/activerecord/test/cases/adapters/postgresql/enum_test.rb
index 6816a6514b..5e5a3158ba 100644
--- a/activerecord/test/cases/adapters/postgresql/enum_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/enum_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 class PostgresqlEnumTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -14,15 +14,15 @@ class PostgresqlEnumTest < ActiveRecord::PostgreSQLTestCase
       @connection.execute <<-SQL
         CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
       SQL
-      @connection.create_table('postgresql_enums') do |t|
+      @connection.create_table("postgresql_enums") do |t|
         t.column :current_mood, :mood
       end
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_enums', if_exists: true
-    @connection.execute 'DROP TYPE IF EXISTS mood'
+    @connection.drop_table "postgresql_enums", if_exists: true
+    @connection.execute "DROP TYPE IF EXISTS mood"
     reset_connection
   end
 
@@ -37,10 +37,10 @@ class PostgresqlEnumTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_enum_defaults
-    @connection.add_column 'postgresql_enums', 'good_mood', :mood, default: 'happy'
+    @connection.add_column "postgresql_enums", "good_mood", :mood, default: "happy"
     PostgresqlEnum.reset_column_information
 
-    assert_equal "happy", PostgresqlEnum.column_defaults['good_mood']
+    assert_equal "happy", PostgresqlEnum.column_defaults["good_mood"]
     assert_equal "happy", PostgresqlEnum.new.good_mood
   ensure
     PostgresqlEnum.reset_column_information
diff --git a/activerecord/test/cases/adapters/postgresql/explain_test.rb b/activerecord/test/cases/adapters/postgresql/explain_test.rb
index b00f8f5706..7493bce4fb 100644
--- a/activerecord/test/cases/adapters/postgresql/explain_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/explain_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
+require "models/developer"
+require "models/computer"
 
 class PostgreSQLExplainTest < ActiveRecord::PostgreSQLTestCase
   fixtures :developers
diff --git a/activerecord/test/cases/adapters/postgresql/full_text_test.rb b/activerecord/test/cases/adapters/postgresql/full_text_test.rb
index bde7513339..5ddfe32007 100644
--- a/activerecord/test/cases/adapters/postgresql/full_text_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/full_text_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlFullTextTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -7,13 +7,13 @@ class PostgresqlFullTextTest < ActiveRecord::PostgreSQLTestCase
 
   setup do
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('tsvectors') do |t|
-      t.tsvector 'text_vector'
+    @connection.create_table("tsvectors") do |t|
+      t.tsvector "text_vector"
     end
   end
 
   teardown do
-    @connection.drop_table 'tsvectors', if_exists: true
+    @connection.drop_table "tsvectors", if_exists: true
   end
 
   def test_tsvector_column
diff --git a/activerecord/test/cases/adapters/postgresql/geometric_test.rb b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
index 66f0a70394..1b7d0cf4f0 100644
--- a/activerecord/test/cases/adapters/postgresql/geometric_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'support/connection_helper'
-require 'support/schema_dumping_helper'
+require "support/connection_helper"
+require "support/schema_dumping_helper"
 
 class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
   include ConnectionHelper
@@ -18,7 +18,7 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
 
   def setup
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_points') do |t|
+    @connection.create_table("postgresql_points") do |t|
       t.point :x
       t.point :y, default: [12.2, 13.3]
       t.point :z, default: "(14.4,15.5)"
@@ -27,14 +27,14 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
       t.point :legacy_y, default: [12.2, 13.3]
       t.point :legacy_z, default: "(14.4,15.5)"
     end
-    @connection.create_table('deprecated_points') do |t|
+    @connection.create_table("deprecated_points") do |t|
       t.point :x
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_points', if_exists: true
-    @connection.drop_table 'deprecated_points', if_exists: true
+    @connection.drop_table "postgresql_points", if_exists: true
+    @connection.drop_table "deprecated_points", if_exists: true
   end
 
   class DeprecatedPoint < ActiveRecord::Base; end
@@ -56,10 +56,10 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_default
-    assert_equal ActiveRecord::Point.new(12.2, 13.3), PostgresqlPoint.column_defaults['y']
+    assert_equal ActiveRecord::Point.new(12.2, 13.3), PostgresqlPoint.column_defaults["y"]
     assert_equal ActiveRecord::Point.new(12.2, 13.3), PostgresqlPoint.new.y
 
-    assert_equal ActiveRecord::Point.new(14.4, 15.5), PostgresqlPoint.column_defaults['z']
+    assert_equal ActiveRecord::Point.new(14.4, 15.5), PostgresqlPoint.column_defaults["z"]
     assert_equal ActiveRecord::Point.new(14.4, 15.5), PostgresqlPoint.new.z
   end
 
@@ -136,10 +136,10 @@ class PostgresqlPointTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_legacy_default
-    assert_equal [12.2, 13.3], PostgresqlPoint.column_defaults['legacy_y']
+    assert_equal [12.2, 13.3], PostgresqlPoint.column_defaults["legacy_y"]
     assert_equal [12.2, 13.3], PostgresqlPoint.new.legacy_y
 
-    assert_equal [14.4, 15.5], PostgresqlPoint.column_defaults['legacy_z']
+    assert_equal [14.4, 15.5], PostgresqlPoint.column_defaults["legacy_z"]
     assert_equal [14.4, 15.5], PostgresqlPoint.new.legacy_z
   end
 
@@ -190,51 +190,51 @@ class PostgresqlGeometricTest < ActiveRecord::PostgreSQLTestCase
   end
 
   teardown do
-    @connection.drop_table 'postgresql_geometrics', if_exists: true
+    @connection.drop_table "postgresql_geometrics", if_exists: true
   end
 
   def test_geometric_types
     g = PostgresqlGeometric.new(
-      :a_line_segment => '(2.0, 3), (5.5, 7.0)',
-      :a_box          => '2.0, 3, 5.5, 7.0',
-      :a_path         => '[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]',
-      :a_polygon      => '((2.0, 3), (5.5, 7.0), (8.5, 11.0))',
-      :a_circle       => '<(5.3, 10.4), 2>'
+      :a_line_segment => "(2.0, 3), (5.5, 7.0)",
+      :a_box          => "2.0, 3, 5.5, 7.0",
+      :a_path         => "[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]",
+      :a_polygon      => "((2.0, 3), (5.5, 7.0), (8.5, 11.0))",
+      :a_circle       => "<(5.3, 10.4), 2>"
     )
 
     g.save!
 
     h = PostgresqlGeometric.find(g.id)
 
-    assert_equal '[(2,3),(5.5,7)]', h.a_line_segment
-    assert_equal '(5.5,7),(2,3)', h.a_box # reordered to store upper right corner then bottom left corner
-    assert_equal '[(2,3),(5.5,7),(8.5,11)]', h.a_path
-    assert_equal '((2,3),(5.5,7),(8.5,11))', h.a_polygon
-    assert_equal '<(5.3,10.4),2>', h.a_circle
+    assert_equal "[(2,3),(5.5,7)]", h.a_line_segment
+    assert_equal "(5.5,7),(2,3)", h.a_box # reordered to store upper right corner then bottom left corner
+    assert_equal "[(2,3),(5.5,7),(8.5,11)]", h.a_path
+    assert_equal "((2,3),(5.5,7),(8.5,11))", h.a_polygon
+    assert_equal "<(5.3,10.4),2>", h.a_circle
   end
 
   def test_alternative_format
     g = PostgresqlGeometric.new(
-      :a_line_segment => '((2.0, 3), (5.5, 7.0))',
-      :a_box          => '(2.0, 3), (5.5, 7.0)',
-      :a_path         => '((2.0, 3), (5.5, 7.0), (8.5, 11.0))',
-      :a_polygon      => '2.0, 3, 5.5, 7.0, 8.5, 11.0',
-      :a_circle       => '((5.3, 10.4), 2)'
+      :a_line_segment => "((2.0, 3), (5.5, 7.0))",
+      :a_box          => "(2.0, 3), (5.5, 7.0)",
+      :a_path         => "((2.0, 3), (5.5, 7.0), (8.5, 11.0))",
+      :a_polygon      => "2.0, 3, 5.5, 7.0, 8.5, 11.0",
+      :a_circle       => "((5.3, 10.4), 2)"
     )
 
     g.save!
 
     h = PostgresqlGeometric.find(g.id)
-    assert_equal '[(2,3),(5.5,7)]', h.a_line_segment
-    assert_equal '(5.5,7),(2,3)', h.a_box   # reordered to store upper right corner then bottom left corner
-    assert_equal '((2,3),(5.5,7),(8.5,11))', h.a_path
-    assert_equal '((2,3),(5.5,7),(8.5,11))', h.a_polygon
-    assert_equal '<(5.3,10.4),2>', h.a_circle
+    assert_equal "[(2,3),(5.5,7)]", h.a_line_segment
+    assert_equal "(5.5,7),(2,3)", h.a_box   # reordered to store upper right corner then bottom left corner
+    assert_equal "((2,3),(5.5,7),(8.5,11))", h.a_path
+    assert_equal "((2,3),(5.5,7),(8.5,11))", h.a_polygon
+    assert_equal "<(5.3,10.4),2>", h.a_circle
   end
 
   def test_geometric_function
-    PostgresqlGeometric.create! a_path: '[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]'  # [ ] is an open path
-    PostgresqlGeometric.create! a_path: '((2.0, 3), (5.5, 7.0), (8.5, 11.0))'  # ( ) is a closed path
+    PostgresqlGeometric.create! a_path: "[(2.0, 3), (5.5, 7.0), (8.5, 11.0)]"  # [ ] is an open path
+    PostgresqlGeometric.create! a_path: "((2.0, 3), (5.5, 7.0), (8.5, 11.0))"  # ( ) is a closed path
 
     objs = PostgresqlGeometric.find_by_sql "SELECT isopen(a_path) FROM postgresql_geometrics ORDER BY id ASC"
     assert_equal [true, false], objs.map(&:isopen)
@@ -270,28 +270,28 @@ class PostgreSQLGeometricLineTest < ActiveRecord::PostgreSQLTestCase
 
   teardown do
     if defined?(@connection)
-      @connection.drop_table 'postgresql_lines', if_exists: true
+      @connection.drop_table "postgresql_lines", if_exists: true
     end
   end
 
   def test_geometric_line_type
     g = PostgresqlLine.new(
-      a_line: '{2.0, 3, 5.5}'
+      a_line: "{2.0, 3, 5.5}"
     )
     g.save!
 
     h = PostgresqlLine.find(g.id)
-    assert_equal '{2,3,5.5}', h.a_line
+    assert_equal "{2,3,5.5}", h.a_line
   end
 
   def test_alternative_format_line_type
     g = PostgresqlLine.new(
-      a_line: '(2.0, 3), (4.0, 6.0)'
+      a_line: "(2.0, 3), (4.0, 6.0)"
     )
     g.save!
 
     h = PostgresqlLine.find(g.id)
-    assert_equal '{1.5,-1,0}', h.a_line
+    assert_equal "{1.5,-1,0}", h.a_line
   end
 
   def test_schema_dumping_for_line_type
diff --git a/activerecord/test/cases/adapters/postgresql/hstore_test.rb b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
index 27cc65a643..b31aba39d9 100644
--- a/activerecord/test/cases/adapters/postgresql/hstore_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
@@ -1,11 +1,11 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 if ActiveRecord::Base.connection.supports_extensions?
   class PostgresqlHstoreTest < ActiveRecord::PostgreSQLTestCase
     include SchemaDumpingHelper
     class Hstore < ActiveRecord::Base
-      self.table_name = 'hstores'
+      self.table_name = "hstores"
 
       store_accessor :settings, :language, :timezone
     end
@@ -13,40 +13,40 @@ if ActiveRecord::Base.connection.supports_extensions?
     def setup
       @connection = ActiveRecord::Base.connection
 
-      unless @connection.extension_enabled?('hstore')
-        @connection.enable_extension 'hstore'
+      unless @connection.extension_enabled?("hstore")
+        @connection.enable_extension "hstore"
         @connection.commit_db_transaction
       end
 
       @connection.reconnect!
 
       @connection.transaction do
-        @connection.create_table('hstores') do |t|
-          t.hstore 'tags', :default => ''
-          t.hstore 'payload', array: true
-          t.hstore 'settings'
+        @connection.create_table("hstores") do |t|
+          t.hstore "tags", :default => ""
+          t.hstore "payload", array: true
+          t.hstore "settings"
         end
       end
       Hstore.reset_column_information
-      @column = Hstore.columns_hash['tags']
+      @column = Hstore.columns_hash["tags"]
       @type = Hstore.type_for_attribute("tags")
     end
 
     teardown do
-      @connection.drop_table 'hstores', if_exists: true
+      @connection.drop_table "hstores", if_exists: true
     end
 
     def test_hstore_included_in_extensions
       assert @connection.respond_to?(:extensions), "connection should have a list of extensions"
-      assert @connection.extensions.include?('hstore'), "extension list should include hstore"
+      assert @connection.extensions.include?("hstore"), "extension list should include hstore"
     end
 
     def test_disable_enable_hstore
-      assert @connection.extension_enabled?('hstore')
-      @connection.disable_extension 'hstore'
-      assert_not @connection.extension_enabled?('hstore')
-      @connection.enable_extension 'hstore'
-      assert @connection.extension_enabled?('hstore')
+      assert @connection.extension_enabled?("hstore")
+      @connection.disable_extension "hstore"
+      assert_not @connection.extension_enabled?("hstore")
+      @connection.enable_extension "hstore"
+      assert @connection.extension_enabled?("hstore")
     ensure
       # Restore column(s) dropped by `drop extension hstore cascade;`
       load_schema
@@ -61,10 +61,10 @@ if ActiveRecord::Base.connection.supports_extensions?
     end
 
     def test_default
-      @connection.add_column 'hstores', 'permissions', :hstore, default: '"users"=>"read", "articles"=>"write"'
+      @connection.add_column "hstores", "permissions", :hstore, default: '"users"=>"read", "articles"=>"write"'
       Hstore.reset_column_information
 
-      assert_equal({"users"=>"read", "articles"=>"write"}, Hstore.column_defaults['permissions'])
+      assert_equal({"users"=>"read", "articles"=>"write"}, Hstore.column_defaults["permissions"])
       assert_equal({"users"=>"read", "articles"=>"write"}, Hstore.new.permissions)
     ensure
       Hstore.reset_column_information
@@ -72,11 +72,11 @@ if ActiveRecord::Base.connection.supports_extensions?
 
     def test_change_table_supports_hstore
       @connection.transaction do
-        @connection.change_table('hstores') do |t|
-          t.hstore 'users', default: ''
+        @connection.change_table("hstores") do |t|
+          t.hstore "users", default: ""
         end
         Hstore.reset_column_information
-        column = Hstore.columns_hash['users']
+        column = Hstore.columns_hash["users"]
         assert_equal :hstore, column.type
 
         raise ActiveRecord::Rollback # reset the schema change
@@ -111,10 +111,10 @@ if ActiveRecord::Base.connection.supports_extensions?
     end
 
     def test_type_cast_hstore
-      assert_equal({'1' => '2'}, @type.deserialize("\"1\"=>\"2\""))
+      assert_equal({"1" => "2"}, @type.deserialize("\"1\"=>\"2\""))
       assert_equal({}, @type.deserialize(""))
-      assert_equal({'key'=>nil}, @type.deserialize('key => NULL'))
-      assert_equal({'c'=>'}','"a"'=>'b "a b'}, @type.deserialize(%q(c=>"}", "\"a\""=>"b \"a b")))
+      assert_equal({"key"=>nil}, @type.deserialize("key => NULL"))
+      assert_equal({"c"=>"}",'"a"'=>'b "a b'}, @type.deserialize(%q(c=>"}", "\"a\""=>"b \"a b")))
     end
 
     def test_with_store_accessors
@@ -156,33 +156,33 @@ if ActiveRecord::Base.connection.supports_extensions?
     end
 
     def test_changes_in_place
-      hstore = Hstore.create!(settings: { 'one' => 'two' })
-      hstore.settings['three'] = 'four'
+      hstore = Hstore.create!(settings: { "one" => "two" })
+      hstore.settings["three"] = "four"
       hstore.save!
       hstore.reload
 
-      assert_equal 'four', hstore.settings['three']
+      assert_equal "four", hstore.settings["three"]
       assert_not hstore.changed?
     end
 
     def test_gen1
-      assert_equal(%q(" "=>""), @type.serialize({' '=>''}))
+      assert_equal(%q(" "=>""), @type.serialize({" "=>""}))
     end
 
     def test_gen2
-      assert_equal(%q(","=>""), @type.serialize({','=>''}))
+      assert_equal(%q(","=>""), @type.serialize({","=>""}))
     end
 
     def test_gen3
-      assert_equal(%q("="=>""), @type.serialize({'='=>''}))
+      assert_equal(%q("="=>""), @type.serialize({"="=>""}))
     end
 
     def test_gen4
-      assert_equal(%q(">"=>""), @type.serialize({'>'=>''}))
+      assert_equal(%q(">"=>""), @type.serialize({">"=>""}))
     end
 
     def test_parse1
-      assert_equal({'a'=>nil,'b'=>nil,'c'=>'NuLl','null'=>'c'}, @type.deserialize('a=>null,b=>NuLl,c=>"NuLl",null=>c'))
+      assert_equal({"a"=>nil,"b"=>nil,"c"=>"NuLl","null"=>"c"}, @type.deserialize('a=>null,b=>NuLl,c=>"NuLl",null=>c'))
     end
 
     def test_parse2
@@ -212,14 +212,14 @@ if ActiveRecord::Base.connection.supports_extensions?
     def test_rewrite
       @connection.execute "insert into hstores (tags) VALUES ('1=>2')"
       x = Hstore.first
-      x.tags = { '"a\'' => 'b' }
+      x.tags = { '"a\'' => "b" }
       assert x.save!
     end
 
     def test_select
       @connection.execute "insert into hstores (tags) VALUES ('1=>2')"
       x = Hstore.first
-      assert_equal({'1' => '2'}, x.tags)
+      assert_equal({"1" => "2"}, x.tags)
     end
 
     def test_array_cycle
@@ -227,61 +227,61 @@ if ActiveRecord::Base.connection.supports_extensions?
     end
 
     def test_array_strings_with_quotes
-      assert_array_cycle([{'this has' => 'some "s that need to be escaped"'}])
+      assert_array_cycle([{"this has" => 'some "s that need to be escaped"'}])
     end
 
     def test_array_strings_with_commas
-      assert_array_cycle([{'this,has' => 'many,values'}])
+      assert_array_cycle([{"this,has" => "many,values"}])
     end
 
     def test_array_strings_with_array_delimiters
-      assert_array_cycle(['{' => '}'])
+      assert_array_cycle(["{" => "}"])
     end
 
     def test_array_strings_with_null_strings
-      assert_array_cycle([{'NULL' => 'NULL'}])
+      assert_array_cycle([{"NULL" => "NULL"}])
     end
 
     def test_contains_nils
-      assert_array_cycle([{'NULL' => nil}])
+      assert_array_cycle([{"NULL" => nil}])
     end
 
     def test_select_multikey
       @connection.execute "insert into hstores (tags) VALUES ('1=>2,2=>3')"
       x = Hstore.first
-      assert_equal({'1' => '2', '2' => '3'}, x.tags)
+      assert_equal({"1" => "2", "2" => "3"}, x.tags)
     end
 
     def test_create
-      assert_cycle('a' => 'b', '1' => '2')
+      assert_cycle("a" => "b", "1" => "2")
     end
 
     def test_nil
-      assert_cycle('a' => nil)
+      assert_cycle("a" => nil)
     end
 
     def test_quotes
-      assert_cycle('a' => 'b"ar', '1"foo' => '2')
+      assert_cycle("a" => 'b"ar', '1"foo' => "2")
     end
 
     def test_whitespace
-      assert_cycle('a b' => 'b ar', '1"foo' => '2')
+      assert_cycle("a b" => "b ar", '1"foo' => "2")
     end
 
     def test_backslash
-      assert_cycle('a\\b' => 'b\\ar', '1"foo' => '2')
+      assert_cycle('a\\b' => 'b\\ar', '1"foo' => "2")
     end
 
     def test_comma
-      assert_cycle('a, b' => 'bar', '1"foo' => '2')
+      assert_cycle("a, b" => "bar", '1"foo' => "2")
     end
 
     def test_arrow
-      assert_cycle('a=>b' => 'bar', '1"foo' => '2')
+      assert_cycle("a=>b" => "bar", '1"foo' => "2")
     end
 
     def test_quoting_special_characters
-      assert_cycle('ca' => 'cà', 'ac' => 'àc')
+      assert_cycle("ca" => "cà", "ac" => "àc")
     end
 
     def test_multiline
diff --git a/activerecord/test/cases/adapters/postgresql/infinity_test.rb b/activerecord/test/cases/adapters/postgresql/infinity_test.rb
index bfda933fa4..19b00258b6 100644
--- a/activerecord/test/cases/adapters/postgresql/infinity_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/infinity_test.rb
@@ -15,7 +15,7 @@ class PostgresqlInfinityTest < ActiveRecord::PostgreSQLTestCase
   end
 
   teardown do
-    @connection.drop_table 'postgresql_infinities', if_exists: true
+    @connection.drop_table "postgresql_infinities", if_exists: true
   end
 
   test "type casting infinity on a float column" do
@@ -25,11 +25,11 @@ class PostgresqlInfinityTest < ActiveRecord::PostgreSQLTestCase
   end
 
   test "type casting string on a float column" do
-    record = PostgresqlInfinity.new(float: 'Infinity')
+    record = PostgresqlInfinity.new(float: "Infinity")
     assert_equal Float::INFINITY, record.float
-    record = PostgresqlInfinity.new(float: '-Infinity')
+    record = PostgresqlInfinity.new(float: "-Infinity")
     assert_equal(-Float::INFINITY, record.float)
-    record = PostgresqlInfinity.new(float: 'NaN')
+    record = PostgresqlInfinity.new(float: "NaN")
     assert_send [record.float, :nan?]
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/json_test.rb b/activerecord/test/cases/adapters/postgresql/json_test.rb
index 663de680b5..8b5a5f1bab 100644
--- a/activerecord/test/cases/adapters/postgresql/json_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/json_test.rb
@@ -1,11 +1,11 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 module PostgresqlJSONSharedTestCases
   include SchemaDumpingHelper
 
   class JsonDataType < ActiveRecord::Base
-    self.table_name = 'json_data_type'
+    self.table_name = "json_data_type"
 
     store_accessor :settings, :resolution
   end
@@ -13,9 +13,9 @@ module PostgresqlJSONSharedTestCases
   def setup
     @connection = ActiveRecord::Base.connection
     begin
-      @connection.create_table('json_data_type') do |t|
-        t.public_send column_type, 'payload', default: {} # t.json 'payload', default: {}
-        t.public_send column_type, 'settings'             # t.json 'settings'
+      @connection.create_table("json_data_type") do |t|
+        t.public_send column_type, "payload", default: {} # t.json 'payload', default: {}
+        t.public_send column_type, "settings"             # t.json 'settings'
       end
     rescue ActiveRecord::StatementInvalid
       skip "do not test on PostgreSQL without #{column_type} type."
@@ -38,10 +38,10 @@ module PostgresqlJSONSharedTestCases
   end
 
   def test_default
-    @connection.add_column 'json_data_type', 'permissions', column_type, default: {"users": "read", "posts": ["read", "write"]}
+    @connection.add_column "json_data_type", "permissions", column_type, default: {"users": "read", "posts": ["read", "write"]}
     JsonDataType.reset_column_information
 
-    assert_equal({"users"=>"read", "posts"=>["read", "write"]}, JsonDataType.column_defaults['permissions'])
+    assert_equal({"users"=>"read", "posts"=>["read", "write"]}, JsonDataType.column_defaults["permissions"])
     assert_equal({"users"=>"read", "posts"=>["read", "write"]}, JsonDataType.new.permissions)
   ensure
     JsonDataType.reset_column_information
@@ -49,11 +49,11 @@ module PostgresqlJSONSharedTestCases
 
   def test_change_table_supports_json
     @connection.transaction do
-      @connection.change_table('json_data_type') do |t|
-        t.public_send column_type, 'users', default: '{}' # t.json 'users', default: '{}'
+      @connection.change_table("json_data_type") do |t|
+        t.public_send column_type, "users", default: "{}" # t.json 'users', default: '{}'
       end
       JsonDataType.reset_column_information
-      column = JsonDataType.columns_hash['users']
+      column = JsonDataType.columns_hash["users"]
       assert_equal column_type, column.type
 
       raise ActiveRecord::Rollback # reset the schema change
@@ -80,31 +80,31 @@ module PostgresqlJSONSharedTestCases
 
     data = "{\"a_key\":\"a_value\"}"
     hash = type.deserialize(data)
-    assert_equal({'a_key' => 'a_value'}, hash)
-    assert_equal({'a_key' => 'a_value'}, type.deserialize(data))
+    assert_equal({"a_key" => "a_value"}, hash)
+    assert_equal({"a_key" => "a_value"}, type.deserialize(data))
 
     assert_equal({}, type.deserialize("{}"))
-    assert_equal({'key'=>nil}, type.deserialize('{"key": null}'))
-    assert_equal({'c'=>'}','"a"'=>'b "a b'}, type.deserialize(%q({"c":"}", "\"a\"":"b \"a b"})))
+    assert_equal({"key"=>nil}, type.deserialize('{"key": null}'))
+    assert_equal({"c"=>"}",'"a"'=>'b "a b'}, type.deserialize(%q({"c":"}", "\"a\"":"b \"a b"})))
   end
 
   def test_rewrite
     @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
     x = JsonDataType.first
-    x.payload = { '"a\'' => 'b' }
+    x.payload = { '"a\'' => "b" }
     assert x.save!
   end
 
   def test_select
     @connection.execute "insert into json_data_type (payload) VALUES ('{\"k\":\"v\"}')"
     x = JsonDataType.first
-    assert_equal({'k' => 'v'}, x.payload)
+    assert_equal({"k" => "v"}, x.payload)
   end
 
   def test_select_multikey
     @connection.execute %q|insert into json_data_type (payload) VALUES ('{"k1":"v1", "k2":"v2", "k3":[1,2,3]}')|
     x = JsonDataType.first
-    assert_equal({'k1' => 'v1', 'k2' => 'v2', 'k3' => [1,2,3]}, x.payload)
+    assert_equal({"k1" => "v1", "k2" => "v2", "k3" => [1,2,3]}, x.payload)
   end
 
   def test_null_json
@@ -116,13 +116,13 @@ module PostgresqlJSONSharedTestCases
   def test_select_array_json_value
     @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
     x = JsonDataType.first
-    assert_equal(['v0', {'k1' => 'v1'}], x.payload)
+    assert_equal(["v0", {"k1" => "v1"}], x.payload)
   end
 
   def test_rewrite_array_json_value
     @connection.execute %q|insert into json_data_type (payload) VALUES ('["v0",{"k1":"v1"}]')|
     x = JsonDataType.first
-    x.payload = ['v1', {'k2' => 'v2'}, 'v3']
+    x.payload = ["v1", {"k2" => "v2"}, "v3"]
     assert x.save!
   end
 
@@ -161,20 +161,20 @@ module PostgresqlJSONSharedTestCases
     json = JsonDataType.new
     assert_not json.changed?
 
-    json.payload = { 'one' => 'two' }
+    json.payload = { "one" => "two" }
     assert json.changed?
     assert json.payload_changed?
 
     json.save!
     assert_not json.changed?
 
-    json.payload['three'] = 'four'
+    json.payload["three"] = "four"
     assert json.payload_changed?
 
     json.save!
     json.reload
 
-    assert_equal({ 'one' => 'two', 'three' => 'four' }, json.payload)
+    assert_equal({ "one" => "two", "three" => "four" }, json.payload)
     assert_not json.changed?
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/ltree_test.rb b/activerecord/test/cases/adapters/postgresql/ltree_test.rb
index 56516c82b4..2b5ac1cac6 100644
--- a/activerecord/test/cases/adapters/postgresql/ltree_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/ltree_test.rb
@@ -1,20 +1,20 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlLtreeTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
   class Ltree < ActiveRecord::Base
-    self.table_name = 'ltrees'
+    self.table_name = "ltrees"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
 
-    enable_extension!('ltree', @connection)
+    enable_extension!("ltree", @connection)
 
     @connection.transaction do
-      @connection.create_table('ltrees') do |t|
-        t.ltree 'path'
+      @connection.create_table("ltrees") do |t|
+        t.ltree "path"
       end
     end
   rescue ActiveRecord::StatementInvalid
@@ -22,28 +22,28 @@ class PostgresqlLtreeTest < ActiveRecord::PostgreSQLTestCase
   end
 
   teardown do
-    @connection.drop_table 'ltrees', if_exists: true
+    @connection.drop_table "ltrees", if_exists: true
   end
 
   def test_column
-    column = Ltree.columns_hash['path']
+    column = Ltree.columns_hash["path"]
     assert_equal :ltree, column.type
     assert_equal "ltree", column.sql_type
     assert_not column.array?
 
-    type = Ltree.type_for_attribute('path')
+    type = Ltree.type_for_attribute("path")
     assert_not type.binary?
   end
 
   def test_write
-    ltree = Ltree.new(path: '1.2.3.4')
+    ltree = Ltree.new(path: "1.2.3.4")
     assert ltree.save!
   end
 
   def test_select
     @connection.execute "insert into ltrees (path) VALUES ('1.2.3')"
     ltree = Ltree.first
-    assert_equal '1.2.3', ltree.path
+    assert_equal "1.2.3", ltree.path
   end
 
   def test_schema_dump_with_shorthand
diff --git a/activerecord/test/cases/adapters/postgresql/money_test.rb b/activerecord/test/cases/adapters/postgresql/money_test.rb
index c031178479..1b5d8362af 100644
--- a/activerecord/test/cases/adapters/postgresql/money_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/money_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -9,14 +9,14 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   setup do
     @connection = ActiveRecord::Base.connection
     @connection.execute("set lc_monetary = 'C'")
-    @connection.create_table('postgresql_moneys', force: true) do |t|
+    @connection.create_table("postgresql_moneys", force: true) do |t|
       t.money "wealth"
       t.money "depth", default: "150.55"
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_moneys', if_exists: true
+    @connection.drop_table "postgresql_moneys", if_exists: true
   end
 
   def test_column
@@ -31,7 +31,7 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_default
-    assert_equal BigDecimal.new("150.55"), PostgresqlMoney.column_defaults['depth']
+    assert_equal BigDecimal.new("150.55"), PostgresqlMoney.column_defaults["depth"]
     assert_equal BigDecimal.new("150.55"), PostgresqlMoney.new.depth
   end
 
@@ -46,7 +46,7 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_money_type_cast
-    type = PostgresqlMoney.type_for_attribute('wealth')
+    type = PostgresqlMoney.type_for_attribute("wealth")
     assert_equal(12345678.12, type.cast("$12,345,678.12"))
     assert_equal(12345678.12, type.cast("$12.345.678,12"))
     assert_equal(-1.15, type.cast("-$1.15"))
@@ -63,7 +63,7 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
     money = PostgresqlMoney.create(wealth: "987.65")
     assert_equal 987.65, money.wealth
 
-    new_value = BigDecimal.new('123.45')
+    new_value = BigDecimal.new("123.45")
     money.wealth = new_value
     money.save!
     money.reload
@@ -80,7 +80,7 @@ class PostgresqlMoneyTest < ActiveRecord::PostgreSQLTestCase
 
   def test_update_all_with_money_big_decimal
     money = PostgresqlMoney.create!
-    PostgresqlMoney.update_all(wealth: '123.45'.to_d)
+    PostgresqlMoney.update_all(wealth: "123.45".to_d)
     money.reload
 
     assert_equal 123.45, money.wealth
diff --git a/activerecord/test/cases/adapters/postgresql/network_test.rb b/activerecord/test/cases/adapters/postgresql/network_test.rb
index fe6ee4e2d9..a33b0ef8a7 100644
--- a/activerecord/test/cases/adapters/postgresql/network_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/network_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlNetworkTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
@@ -7,15 +7,15 @@ class PostgresqlNetworkTest < ActiveRecord::PostgreSQLTestCase
 
   setup do
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_network_addresses', force: true) do |t|
-      t.inet 'inet_address', default: "192.168.1.1"
-      t.cidr 'cidr_address', default: "192.168.1.0/24"
-      t.macaddr 'mac_address', default: "ff:ff:ff:ff:ff:ff"
+    @connection.create_table("postgresql_network_addresses", force: true) do |t|
+      t.inet "inet_address", default: "192.168.1.1"
+      t.cidr "cidr_address", default: "192.168.1.0/24"
+      t.macaddr "mac_address", default: "ff:ff:ff:ff:ff:ff"
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_network_addresses', if_exists: true
+    @connection.drop_table "postgresql_network_addresses", if_exists: true
   end
 
   def test_cidr_column
@@ -49,33 +49,33 @@ class PostgresqlNetworkTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_network_types
-    PostgresqlNetworkAddress.create(cidr_address: '192.168.0.0/24',
-                                    inet_address: '172.16.1.254/32',
-                                    mac_address: '01:23:45:67:89:0a')
+    PostgresqlNetworkAddress.create(cidr_address: "192.168.0.0/24",
+                                    inet_address: "172.16.1.254/32",
+                                    mac_address: "01:23:45:67:89:0a")
 
     address = PostgresqlNetworkAddress.first
-    assert_equal IPAddr.new('192.168.0.0/24'), address.cidr_address
-    assert_equal IPAddr.new('172.16.1.254'), address.inet_address
-    assert_equal '01:23:45:67:89:0a', address.mac_address
+    assert_equal IPAddr.new("192.168.0.0/24"), address.cidr_address
+    assert_equal IPAddr.new("172.16.1.254"), address.inet_address
+    assert_equal "01:23:45:67:89:0a", address.mac_address
 
-    address.cidr_address = '10.1.2.3/32'
-    address.inet_address = '10.0.0.0/8'
-    address.mac_address = 'bc:de:f0:12:34:56'
+    address.cidr_address = "10.1.2.3/32"
+    address.inet_address = "10.0.0.0/8"
+    address.mac_address = "bc:de:f0:12:34:56"
 
     address.save!
     assert address.reload
-    assert_equal IPAddr.new('10.1.2.3/32'), address.cidr_address
-    assert_equal IPAddr.new('10.0.0.0/8'), address.inet_address
-    assert_equal 'bc:de:f0:12:34:56', address.mac_address
+    assert_equal IPAddr.new("10.1.2.3/32"), address.cidr_address
+    assert_equal IPAddr.new("10.0.0.0/8"), address.inet_address
+    assert_equal "bc:de:f0:12:34:56", address.mac_address
   end
 
   def test_invalid_network_address
-    invalid_address = PostgresqlNetworkAddress.new(cidr_address: 'invalid addr',
-                                                   inet_address: 'invalid addr')
+    invalid_address = PostgresqlNetworkAddress.new(cidr_address: "invalid addr",
+                                                   inet_address: "invalid addr")
     assert_nil invalid_address.cidr_address
     assert_nil invalid_address.inet_address
-    assert_equal 'invalid addr', invalid_address.cidr_address_before_type_cast
-    assert_equal 'invalid addr', invalid_address.inet_address_before_type_cast
+    assert_equal "invalid addr", invalid_address.cidr_address_before_type_cast
+    assert_equal "invalid addr", invalid_address.inet_address_before_type_cast
     assert invalid_address.save
 
     invalid_address.reload
diff --git a/activerecord/test/cases/adapters/postgresql/numbers_test.rb b/activerecord/test/cases/adapters/postgresql/numbers_test.rb
index ba7e7dc9a3..834354dcc9 100644
--- a/activerecord/test/cases/adapters/postgresql/numbers_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/numbers_test.rb
@@ -5,14 +5,14 @@ class PostgresqlNumberTest < ActiveRecord::PostgreSQLTestCase
 
   setup do
     @connection = ActiveRecord::Base.connection
-    @connection.create_table('postgresql_numbers', force: true) do |t|
-      t.column 'single', 'REAL'
-      t.column 'double', 'DOUBLE PRECISION'
+    @connection.create_table("postgresql_numbers", force: true) do |t|
+      t.column "single", "REAL"
+      t.column "double", "DOUBLE PRECISION"
     end
   end
 
   teardown do
-    @connection.drop_table 'postgresql_numbers', if_exists: true
+    @connection.drop_table "postgresql_numbers", if_exists: true
   end
 
   def test_data_type
diff --git a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
index 9832df7839..cd2b2d5bc9 100644
--- a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'support/ddl_helper'
-require 'support/connection_helper'
+require "support/ddl_helper"
+require "support/connection_helper"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -15,15 +15,15 @@ module ActiveRecord
 
       def test_bad_connection
         assert_raise ActiveRecord::NoDatabaseError do
-          configuration = ActiveRecord::Base.configurations['arunit'].merge(database: 'should_not_exist-cinco-dog-db')
+          configuration = ActiveRecord::Base.configurations["arunit"].merge(database: "should_not_exist-cinco-dog-db")
           connection = ActiveRecord::Base.postgresql_connection(configuration)
-          connection.exec_query('SELECT 1')
+          connection.exec_query("SELECT 1")
         end
       end
 
       def test_valid_column
         with_example_table do
-          column = @connection.columns('ex').find { |col| col.name == 'id' }
+          column = @connection.columns("ex").find { |col| col.name == "id" }
           assert @connection.valid_type?(column.type)
         end
       end
@@ -34,144 +34,144 @@ module ActiveRecord
 
       def test_primary_key
         with_example_table do
-          assert_equal 'id', @connection.primary_key('ex')
+          assert_equal "id", @connection.primary_key("ex")
         end
       end
 
       def test_primary_key_works_tables_containing_capital_letters
-        assert_equal 'id', @connection.primary_key('CamelCase')
+        assert_equal "id", @connection.primary_key("CamelCase")
       end
 
       def test_non_standard_primary_key
-        with_example_table 'data character varying(255) primary key' do
-          assert_equal 'data', @connection.primary_key('ex')
+        with_example_table "data character varying(255) primary key" do
+          assert_equal "data", @connection.primary_key("ex")
         end
       end
 
       def test_primary_key_returns_nil_for_no_pk
-        with_example_table 'id integer' do
-          assert_nil @connection.primary_key('ex')
+        with_example_table "id integer" do
+          assert_nil @connection.primary_key("ex")
         end
       end
 
       def test_primary_key_raises_error_if_table_not_found
         assert_raises(ActiveRecord::StatementInvalid) do
-          @connection.primary_key('unobtainium')
+          @connection.primary_key("unobtainium")
         end
       end
 
       def test_exec_insert_with_returning_disabled
         connection = connection_without_insert_returning
-        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], 'id', 'postgresql_partitioned_table_parent_id_seq')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], "id", "postgresql_partitioned_table_parent_id_seq")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
       def test_exec_insert_with_returning_disabled_and_no_sequence_name_given
         connection = connection_without_insert_returning
-        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], 'id')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert("insert into postgresql_partitioned_table_parent (number) VALUES (1)", nil, [], "id")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
       def test_exec_insert_default_values_with_returning_disabled_and_no_sequence_name_given
         connection = connection_without_insert_returning
-        result = connection.exec_insert("insert into postgresql_partitioned_table_parent DEFAULT VALUES", nil, [], 'id')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert("insert into postgresql_partitioned_table_parent DEFAULT VALUES", nil, [], "id")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
       def test_exec_insert_default_values_quoted_schema_with_returning_disabled_and_no_sequence_name_given
         connection = connection_without_insert_returning
-        result = connection.exec_insert('insert into "public"."postgresql_partitioned_table_parent" DEFAULT VALUES', nil, [], 'id')
-        expect = connection.query('select max(id) from postgresql_partitioned_table_parent').first.first
+        result = connection.exec_insert('insert into "public"."postgresql_partitioned_table_parent" DEFAULT VALUES', nil, [], "id")
+        expect = connection.query("select max(id) from postgresql_partitioned_table_parent").first.first
         assert_equal expect.to_i, result.rows.first.first
       end
 
       def test_sql_for_insert_with_returning_disabled
         connection = connection_without_insert_returning
-        sql, binds = connection.sql_for_insert('sql', nil, nil, nil, 'binds')
-        assert_equal ['sql', 'binds'], [sql, binds]
+        sql, binds = connection.sql_for_insert("sql", nil, nil, nil, "binds")
+        assert_equal ["sql", "binds"], [sql, binds]
       end
 
       def test_serial_sequence
-        assert_equal 'public.accounts_id_seq',
-          @connection.serial_sequence('accounts', 'id')
+        assert_equal "public.accounts_id_seq",
+          @connection.serial_sequence("accounts", "id")
 
         assert_raises(ActiveRecord::StatementInvalid) do
-          @connection.serial_sequence('zomg', 'id')
+          @connection.serial_sequence("zomg", "id")
         end
       end
 
       def test_default_sequence_name
-        assert_equal 'public.accounts_id_seq',
-          @connection.default_sequence_name('accounts', 'id')
+        assert_equal "public.accounts_id_seq",
+          @connection.default_sequence_name("accounts", "id")
 
-        assert_equal 'public.accounts_id_seq',
-          @connection.default_sequence_name('accounts')
+        assert_equal "public.accounts_id_seq",
+          @connection.default_sequence_name("accounts")
       end
 
       def test_default_sequence_name_bad_table
-        assert_equal 'zomg_id_seq',
-          @connection.default_sequence_name('zomg', 'id')
+        assert_equal "zomg_id_seq",
+          @connection.default_sequence_name("zomg", "id")
 
-        assert_equal 'zomg_id_seq',
-          @connection.default_sequence_name('zomg')
+        assert_equal "zomg_id_seq",
+          @connection.default_sequence_name("zomg")
       end
 
       def test_pk_and_sequence_for
         with_example_table do
-          pk, seq = @connection.pk_and_sequence_for('ex')
-          assert_equal 'id', pk
-          assert_equal @connection.default_sequence_name('ex', 'id'), seq.to_s
+          pk, seq = @connection.pk_and_sequence_for("ex")
+          assert_equal "id", pk
+          assert_equal @connection.default_sequence_name("ex", "id"), seq.to_s
         end
       end
 
       def test_pk_and_sequence_for_with_non_standard_primary_key
-        with_example_table 'code serial primary key' do
-          pk, seq = @connection.pk_and_sequence_for('ex')
-          assert_equal 'code', pk
-          assert_equal @connection.default_sequence_name('ex', 'code'), seq.to_s
+        with_example_table "code serial primary key" do
+          pk, seq = @connection.pk_and_sequence_for("ex")
+          assert_equal "code", pk
+          assert_equal @connection.default_sequence_name("ex", "code"), seq.to_s
         end
       end
 
       def test_pk_and_sequence_for_returns_nil_if_no_seq
-        with_example_table 'id integer primary key' do
-          assert_nil @connection.pk_and_sequence_for('ex')
+        with_example_table "id integer primary key" do
+          assert_nil @connection.pk_and_sequence_for("ex")
         end
       end
 
       def test_pk_and_sequence_for_returns_nil_if_no_pk
-        with_example_table 'id integer' do
-          assert_nil @connection.pk_and_sequence_for('ex')
+        with_example_table "id integer" do
+          assert_nil @connection.pk_and_sequence_for("ex")
         end
       end
 
       def test_pk_and_sequence_for_returns_nil_if_table_not_found
-        assert_nil @connection.pk_and_sequence_for('unobtainium')
+        assert_nil @connection.pk_and_sequence_for("unobtainium")
       end
 
       def test_pk_and_sequence_for_with_collision_pg_class_oid
-        @connection.exec_query('create table ex(id serial primary key)')
-        @connection.exec_query('create table ex2(id serial primary key)')
+        @connection.exec_query("create table ex(id serial primary key)")
+        @connection.exec_query("create table ex2(id serial primary key)")
 
         correct_depend_record = [
           "'pg_class'::regclass",
           "'ex_id_seq'::regclass",
-          '0',
+          "0",
           "'pg_class'::regclass",
           "'ex'::regclass",
-          '1',
+          "1",
           "'a'"
         ]
 
         collision_depend_record = [
           "'pg_attrdef'::regclass",
           "'ex2_id_seq'::regclass",
-          '0',
+          "0",
           "'pg_class'::regclass",
           "'ex'::regclass",
-          '1',
+          "1",
           "'a'"
         ]
 
@@ -185,15 +185,15 @@ module ActiveRecord
           "INSERT INTO pg_depend VALUES(#{correct_depend_record.join(',')})"
         )
 
-        seq = @connection.pk_and_sequence_for('ex').last
+        seq = @connection.pk_and_sequence_for("ex").last
         assert_equal PostgreSQL::Name.new("public", "ex_id_seq"), seq
 
         @connection.exec_query(
           "DELETE FROM pg_depend WHERE objid = 'ex2_id_seq'::regclass AND refobjid = 'ex'::regclass AND deptype = 'a'"
         )
       ensure
-        @connection.drop_table 'ex', if_exists: true
-        @connection.drop_table 'ex2', if_exists: true
+        @connection.drop_table "ex", if_exists: true
+        @connection.drop_table "ex2", if_exists: true
       end
 
       def test_table_alias_length
@@ -204,74 +204,74 @@ module ActiveRecord
 
       def test_exec_no_binds
         with_example_table do
-          result = @connection.exec_query('SELECT id, data FROM ex')
+          result = @connection.exec_query("SELECT id, data FROM ex")
           assert_equal 0, result.rows.length
           assert_equal 2, result.columns.length
           assert_equal %w{ id data }, result.columns
 
-          string = @connection.quote('foo')
+          string = @connection.quote("foo")
           @connection.exec_query("INSERT INTO ex (id, data) VALUES (1, #{string})")
-          result = @connection.exec_query('SELECT id, data FROM ex')
+          result = @connection.exec_query("SELECT id, data FROM ex")
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
       if ActiveRecord::Base.connection.prepared_statements
         def test_exec_with_binds
           with_example_table do
-            string = @connection.quote('foo')
+            string = @connection.quote("foo")
             @connection.exec_query("INSERT INTO ex (id, data) VALUES (1, #{string})")
 
             bind = Relation::QueryAttribute.new("id", 1, Type::Value.new)
-            result = @connection.exec_query('SELECT id, data FROM ex WHERE id = $1', nil, [bind])
+            result = @connection.exec_query("SELECT id, data FROM ex WHERE id = $1", nil, [bind])
 
             assert_equal 1, result.rows.length
             assert_equal 2, result.columns.length
 
-            assert_equal [[1, 'foo']], result.rows
+            assert_equal [[1, "foo"]], result.rows
           end
         end
 
         def test_exec_typecasts_bind_vals
           with_example_table do
-            string = @connection.quote('foo')
+            string = @connection.quote("foo")
             @connection.exec_query("INSERT INTO ex (id, data) VALUES (1, #{string})")
 
             bind = Relation::QueryAttribute.new("id", "1-fuu", Type::Integer.new)
-            result = @connection.exec_query('SELECT id, data FROM ex WHERE id = $1', nil, [bind])
+            result = @connection.exec_query("SELECT id, data FROM ex WHERE id = $1", nil, [bind])
 
             assert_equal 1, result.rows.length
             assert_equal 2, result.columns.length
 
-            assert_equal [[1, 'foo']], result.rows
+            assert_equal [[1, "foo"]], result.rows
           end
         end
       end
 
       def test_partial_index
         with_example_table do
-          @connection.add_index 'ex', %w{ id number }, :name => 'partial', :where => "number > 100"
-          index = @connection.indexes('ex').find { |idx| idx.name == 'partial' }
+          @connection.add_index "ex", %w{ id number }, :name => "partial", :where => "number > 100"
+          index = @connection.indexes("ex").find { |idx| idx.name == "partial" }
           assert_equal "(number > 100)", index.where
         end
       end
 
       def test_expression_index
         with_example_table do
-          @connection.add_index 'ex', 'mod(id, 10), abs(number)', name: 'expression'
-          index = @connection.indexes('ex').find { |idx| idx.name == 'expression' }
-          assert_equal 'mod(id, 10), abs(number)', index.columns
+          @connection.add_index "ex", "mod(id, 10), abs(number)", name: "expression"
+          index = @connection.indexes("ex").find { |idx| idx.name == "expression" }
+          assert_equal "mod(id, 10), abs(number)", index.columns
         end
       end
 
       def test_index_with_opclass
         with_example_table do
-          @connection.add_index 'ex', 'data varchar_pattern_ops', name: 'with_opclass'
-          index = @connection.indexes('ex').find { |idx| idx.name == 'with_opclass' }
-          assert_equal 'data varchar_pattern_ops', index.columns
+          @connection.add_index "ex", "data varchar_pattern_ops", name: "with_opclass"
+          index = @connection.indexes("ex").find { |idx| idx.name == "with_opclass" }
+          assert_equal "data varchar_pattern_ops", index.columns
         end
       end
 
@@ -292,8 +292,8 @@ module ActiveRecord
 
       def test_columns_for_distinct_with_case
         assert_equal(
-          'posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0',
-          @connection.columns_for_distinct('posts.id',
+          "posts.id, CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END AS alias_0",
+          @connection.columns_for_distinct("posts.id",
             ["CASE WHEN author.is_active THEN UPPER(author.name) ELSE UPPER(author.email) END"])
         )
       end
@@ -374,7 +374,7 @@ module ActiveRecord
       def test_unparsed_defaults_are_at_least_set_when_saving
         with_example_table "id SERIAL PRIMARY KEY, number INTEGER NOT NULL DEFAULT (4 + 4) * 2 / 4" do
           number_klass = Class.new(ActiveRecord::Base) do
-            self.table_name = 'ex'
+            self.table_name = "ex"
           end
           column = number_klass.columns_hash["number"]
           assert_nil column.default
@@ -390,12 +390,12 @@ module ActiveRecord
 
       private
 
-      def with_example_table(definition = 'id serial primary key, number integer, data character varying(255)', &block)
-        super(@connection, 'ex', definition, &block)
+      def with_example_table(definition = "id serial primary key, number integer, data character varying(255)", &block)
+        super(@connection, "ex", definition, &block)
       end
 
       def connection_without_insert_returning
-        ActiveRecord::Base.postgresql_connection(ActiveRecord::Base.configurations['arunit'].merge(:insert_returning => false))
+        ActiveRecord::Base.postgresql_connection(ActiveRecord::Base.configurations["arunit"].merge(:insert_returning => false))
       end
     end
   end
diff --git a/activerecord/test/cases/adapters/postgresql/quoting_test.rb b/activerecord/test/cases/adapters/postgresql/quoting_test.rb
index 5e6f4dbbb8..865a3a5098 100644
--- a/activerecord/test/cases/adapters/postgresql/quoting_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/quoting_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'ipaddr'
+require "ipaddr"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -10,11 +10,11 @@ module ActiveRecord
         end
 
         def test_type_cast_true
-          assert_equal 't', @conn.type_cast(true)
+          assert_equal "t", @conn.type_cast(true)
         end
 
         def test_type_cast_false
-          assert_equal 'f', @conn.type_cast(false)
+          assert_equal "f", @conn.type_cast(false)
         end
 
         def test_quote_float_nan
diff --git a/activerecord/test/cases/adapters/postgresql/range_test.rb b/activerecord/test/cases/adapters/postgresql/range_test.rb
index 0edfa4ed9d..3f819f7bd5 100644
--- a/activerecord/test/cases/adapters/postgresql/range_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/range_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 if ActiveRecord::Base.connection.respond_to?(:supports_ranges?) && ActiveRecord::Base.connection.supports_ranges?
   class PostgresqlRange < ActiveRecord::Base
@@ -23,7 +23,7 @@ if ActiveRecord::Base.connection.respond_to?(:supports_ranges?) && ActiveRecord:
             );
 _SQL
 
-          @connection.create_table('postgresql_ranges') do |t|
+          @connection.create_table("postgresql_ranges") do |t|
             t.daterange :date_range
             t.numrange :num_range
             t.tsrange :ts_range
@@ -32,7 +32,7 @@ _SQL
             t.int8range :int8_range
           end
 
-          @connection.add_column 'postgresql_ranges', 'float_range', 'floatrange'
+          @connection.add_column "postgresql_ranges", "float_range", "floatrange"
         end
         PostgresqlRange.reset_column_information
       rescue ActiveRecord::StatementInvalid
@@ -93,8 +93,8 @@ _SQL
     end
 
     teardown do
-      @connection.drop_table 'postgresql_ranges', if_exists: true
-      @connection.execute 'DROP TYPE IF EXISTS floatrange'
+      @connection.drop_table "postgresql_ranges", if_exists: true
+      @connection.execute "DROP TYPE IF EXISTS floatrange"
       reset_connection
     end
 
@@ -132,10 +132,10 @@ _SQL
     end
 
     def test_numrange_values
-      assert_equal BigDecimal.new('0.1')..BigDecimal.new('0.2'), @first_range.num_range
-      assert_equal BigDecimal.new('0.1')...BigDecimal.new('0.2'), @second_range.num_range
-      assert_equal BigDecimal.new('0.1')...BigDecimal.new('Infinity'), @third_range.num_range
-      assert_equal BigDecimal.new('-Infinity')...BigDecimal.new('Infinity'), @fourth_range.num_range
+      assert_equal BigDecimal.new("0.1")..BigDecimal.new("0.2"), @first_range.num_range
+      assert_equal BigDecimal.new("0.1")...BigDecimal.new("0.2"), @second_range.num_range
+      assert_equal BigDecimal.new("0.1")...BigDecimal.new("Infinity"), @third_range.num_range
+      assert_equal BigDecimal.new("-Infinity")...BigDecimal.new("Infinity"), @fourth_range.num_range
       assert_nil @empty_range.num_range
     end
 
@@ -148,8 +148,8 @@ _SQL
     end
 
     def test_tstzrange_values
-      assert_equal Time.parse('2010-01-01 09:30:00 UTC')..Time.parse('2011-01-01 17:30:00 UTC'), @first_range.tstz_range
-      assert_equal Time.parse('2010-01-01 09:30:00 UTC')...Time.parse('2011-01-01 17:30:00 UTC'), @second_range.tstz_range
+      assert_equal Time.parse("2010-01-01 09:30:00 UTC")..Time.parse("2011-01-01 17:30:00 UTC"), @first_range.tstz_range
+      assert_equal Time.parse("2010-01-01 09:30:00 UTC")...Time.parse("2011-01-01 17:30:00 UTC"), @second_range.tstz_range
       assert_equal(-Float::INFINITY...Float::INFINITY, @fourth_range.tstz_range)
       assert_nil @empty_range.tstz_range
     end
@@ -183,17 +183,17 @@ _SQL
     end
 
     def test_create_tstzrange
-      tstzrange = Time.parse('2010-01-01 14:30:00 +0100')...Time.parse('2011-02-02 14:30:00 CDT')
+      tstzrange = Time.parse("2010-01-01 14:30:00 +0100")...Time.parse("2011-02-02 14:30:00 CDT")
       round_trip(@new_range, :tstz_range, tstzrange)
       assert_equal @new_range.tstz_range, tstzrange
-      assert_equal @new_range.tstz_range, Time.parse('2010-01-01 13:30:00 UTC')...Time.parse('2011-02-02 19:30:00 UTC')
+      assert_equal @new_range.tstz_range, Time.parse("2010-01-01 13:30:00 UTC")...Time.parse("2011-02-02 19:30:00 UTC")
     end
 
     def test_update_tstzrange
       assert_equal_round_trip(@first_range, :tstz_range,
-                              Time.parse('2010-01-01 14:30:00 CDT')...Time.parse('2011-02-02 14:30:00 CET'))
+                              Time.parse("2010-01-01 14:30:00 CDT")...Time.parse("2011-02-02 14:30:00 CET"))
       assert_nil_round_trip(@first_range, :tstz_range,
-                            Time.parse('2010-01-01 14:30:00 +0100')...Time.parse('2010-01-01 13:30:00 +0000'))
+                            Time.parse("2010-01-01 14:30:00 +0100")...Time.parse("2010-01-01 13:30:00 +0000"))
     end
 
     def test_create_tsrange
@@ -232,14 +232,14 @@ _SQL
 
     def test_create_numrange
       assert_equal_round_trip(@new_range, :num_range,
-                              BigDecimal.new('0.5')...BigDecimal.new('1'))
+                              BigDecimal.new("0.5")...BigDecimal.new("1"))
     end
 
     def test_update_numrange
       assert_equal_round_trip(@first_range, :num_range,
-                              BigDecimal.new('0.5')...BigDecimal.new('1'))
+                              BigDecimal.new("0.5")...BigDecimal.new("1"))
       assert_nil_round_trip(@first_range, :num_range,
-                            BigDecimal.new('0.5')...BigDecimal.new('0.5'))
+                            BigDecimal.new("0.5")...BigDecimal.new("0.5"))
     end
 
     def test_create_daterange
diff --git a/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
index c895ab9db5..6997044d81 100644
--- a/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
@@ -1,5 +1,5 @@
-require 'cases/helper'
-require 'support/connection_helper'
+require "cases/helper"
+require "support/connection_helper"
 
 class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
   self.use_transactional_tests = false
@@ -14,7 +14,7 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
     def execute(sql)
       if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
         super "BROKEN;" rescue nil # put transaction in broken state
-        raise ActiveRecord::StatementInvalid, 'PG::InsufficientPrivilege'
+        raise ActiveRecord::StatementInvalid, "PG::InsufficientPrivilege"
       else
         super
       end
@@ -24,7 +24,7 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
   module ProgrammerMistake
     def execute(sql)
       if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
-        raise ArgumentError, 'something is not right.'
+        raise ArgumentError, "something is not right."
       else
         super
       end
@@ -48,10 +48,10 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
     warning = capture(:stderr) do
       e = assert_raises(ActiveRecord::InvalidForeignKey) do
         @connection.disable_referential_integrity do
-          raise ActiveRecord::InvalidForeignKey, 'Should be re-raised'
+          raise ActiveRecord::InvalidForeignKey, "Should be re-raised"
         end
       end
-      assert_equal 'Should be re-raised', e.message
+      assert_equal "Should be re-raised", e.message
     end
     assert_match (/WARNING: Rails was not able to disable referential integrity/), warning
     assert_match (/cause: PG::InsufficientPrivilege/), warning
@@ -63,10 +63,10 @@ class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
     warning = capture(:stderr) do
       e = assert_raises(ActiveRecord::StatementInvalid) do
         @connection.disable_referential_integrity do
-          raise ActiveRecord::StatementInvalid, 'Should be re-raised'
+          raise ActiveRecord::StatementInvalid, "Should be re-raised"
         end
       end
-      assert_equal 'Should be re-raised', e.message
+      assert_equal "Should be re-raised", e.message
     end
     assert warning.blank?, "expected no warnings but got:\n#{warning}"
   end
diff --git a/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb b/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
index 285a92f60e..7b565b348e 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_authorization_test.rb
@@ -6,12 +6,12 @@ end
 class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
   self.use_transactional_tests = false
 
-  TABLE_NAME = 'schema_things'
+  TABLE_NAME = "schema_things"
   COLUMNS = [
-    'id serial primary key',
-    'name character varying(50)'
+    "id serial primary key",
+    "name character varying(50)"
   ]
-  USERS = ['rails_pg_schema_user1', 'rails_pg_schema_user2']
+  USERS = ["rails_pg_schema_user1", "rails_pg_schema_user2"]
 
   def setup
     @connection = ActiveRecord::Base.connection
@@ -45,7 +45,7 @@ class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
 
   def test_session_auth=
     assert_raise(ActiveRecord::StatementInvalid) do
-      @connection.session_auth = 'DEFAULT'
+      @connection.session_auth = "DEFAULT"
       @connection.execute "SELECT * FROM #{TABLE_NAME}"
     end
   end
@@ -68,7 +68,7 @@ class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
         USERS.each do |u|
           @connection.clear_cache!
           set_session_auth u
-          assert_equal u, @connection.select_value("SELECT name FROM #{TABLE_NAME} WHERE id = $1", 'SQL', [bind_param(1)])
+          assert_equal u, @connection.select_value("SELECT name FROM #{TABLE_NAME} WHERE id = $1", "SQL", [bind_param(1)])
           set_session_auth
         end
       end
@@ -90,9 +90,9 @@ class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
     assert_nothing_raised do
       USERS.each do |u|
         set_session_auth u
-        st = SchemaThing.new :name => 'TEST1'
+        st = SchemaThing.new :name => "TEST1"
         st.save!
-        st = SchemaThing.new :id => 5, :name => 'TEST2'
+        st = SchemaThing.new :id => 5, :name => "TEST2"
         st.save!
         set_session_auth
       end
@@ -110,7 +110,7 @@ class SchemaAuthorizationTest < ActiveRecord::PostgreSQLTestCase
 
   private
     def set_session_auth auth = nil
-       @connection.session_auth =  auth || 'default'
+       @connection.session_auth =  auth || "default"
     end
 
     def bind_param(value)
diff --git a/activerecord/test/cases/adapters/postgresql/schema_test.rb b/activerecord/test/cases/adapters/postgresql/schema_test.rb
index 52ef07f654..029314874e 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'models/default'
-require 'support/schema_dumping_helper'
+require "models/default"
+require "support/schema_dumping_helper"
 
 module PGSchemaHelper
   def with_schema_search_path(schema_search_path)
@@ -17,32 +17,32 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   include PGSchemaHelper
   self.use_transactional_tests = false
 
-  SCHEMA_NAME = 'test_schema'
-  SCHEMA2_NAME = 'test_schema2'
-  TABLE_NAME = 'things'
-  CAPITALIZED_TABLE_NAME = 'Things'
-  INDEX_A_NAME = 'a_index_things_on_name'
-  INDEX_B_NAME = 'b_index_things_on_different_columns_in_each_schema'
-  INDEX_C_NAME = 'c_index_full_text_search'
-  INDEX_D_NAME = 'd_index_things_on_description_desc'
-  INDEX_E_NAME = 'e_index_things_on_name_vector'
-  INDEX_A_COLUMN = 'name'
-  INDEX_B_COLUMN_S1 = 'email'
-  INDEX_B_COLUMN_S2 = 'moment'
+  SCHEMA_NAME = "test_schema"
+  SCHEMA2_NAME = "test_schema2"
+  TABLE_NAME = "things"
+  CAPITALIZED_TABLE_NAME = "Things"
+  INDEX_A_NAME = "a_index_things_on_name"
+  INDEX_B_NAME = "b_index_things_on_different_columns_in_each_schema"
+  INDEX_C_NAME = "c_index_full_text_search"
+  INDEX_D_NAME = "d_index_things_on_description_desc"
+  INDEX_E_NAME = "e_index_things_on_name_vector"
+  INDEX_A_COLUMN = "name"
+  INDEX_B_COLUMN_S1 = "email"
+  INDEX_B_COLUMN_S2 = "moment"
   INDEX_C_COLUMN = %q{(to_tsvector('english', coalesce(things.name, '')))}
-  INDEX_D_COLUMN = 'description'
-  INDEX_E_COLUMN = 'name_vector'
+  INDEX_D_COLUMN = "description"
+  INDEX_E_COLUMN = "name_vector"
   COLUMNS = [
-    'id integer',
-    'name character varying(50)',
-    'email character varying(50)',
-    'description character varying(100)',
-    'name_vector tsvector',
-    'moment timestamp without time zone default now()'
+    "id integer",
+    "name character varying(50)",
+    "email character varying(50)",
+    "description character varying(100)",
+    "name_vector tsvector",
+    "moment timestamp without time zone default now()"
   ]
-  PK_TABLE_NAME = 'table_with_pk'
-  UNMATCHED_SEQUENCE_NAME = 'unmatched_primary_key_default_value_seq'
-  UNMATCHED_PK_TABLE_NAME = 'table_with_unmatched_sequence_for_pk'
+  PK_TABLE_NAME = "table_with_pk"
+  UNMATCHED_SEQUENCE_NAME = "unmatched_primary_key_default_value_seq"
+  UNMATCHED_PK_TABLE_NAME = "table_with_unmatched_sequence_for_pk"
 
   class Thing1 < ActiveRecord::Base
     self.table_name = "test_schema.things"
@@ -61,7 +61,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   class Thing5 < ActiveRecord::Base
-    self.table_name = 'things'
+    self.table_name = "things"
   end
 
   class Song < ActiveRecord::Base
@@ -168,21 +168,21 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_raise_wrapped_exception_on_bad_prepare
     assert_raises(ActiveRecord::StatementInvalid) do
-      @connection.exec_query "select * from developers where id = ?", 'sql', [bind_param(1)]
+      @connection.exec_query "select * from developers where id = ?", "sql", [bind_param(1)]
     end
   end
 
   if ActiveRecord::Base.connection.prepared_statements
     def test_schema_change_with_prepared_stmt
       altered = false
-      @connection.exec_query "select * from developers where id = $1", 'sql', [bind_param(1)]
-      @connection.exec_query "alter table developers add column zomg int", 'sql', []
+      @connection.exec_query "select * from developers where id = $1", "sql", [bind_param(1)]
+      @connection.exec_query "alter table developers add column zomg int", "sql", []
       altered = true
-      @connection.exec_query "select * from developers where id = $1", 'sql', [bind_param(1)]
+      @connection.exec_query "select * from developers where id = $1", "sql", [bind_param(1)]
     ensure
       # We are not using DROP COLUMN IF EXISTS because that syntax is only
       # supported by pg 9.X
-      @connection.exec_query("alter table developers drop column zomg", 'sql', []) if altered
+      @connection.exec_query("alter table developers drop column zomg", "sql", []) if altered
     end
   end
 
@@ -200,7 +200,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_data_source_exists_when_not_on_schema_search_path
-    with_schema_search_path('PUBLIC') do
+    with_schema_search_path("PUBLIC") do
       assert(!@connection.data_source_exists?(TABLE_NAME), "data_source exists but should not be found")
     end
   end
@@ -246,9 +246,9 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_proper_encoding_of_table_name
-    assert_equal '"table_name"', @connection.quote_table_name('table_name')
+    assert_equal '"table_name"', @connection.quote_table_name("table_name")
     assert_equal '"table.name"', @connection.quote_table_name('"table.name"')
-    assert_equal '"schema_name"."table_name"', @connection.quote_table_name('schema_name.table_name')
+    assert_equal '"schema_name"."table_name"', @connection.quote_table_name("schema_name.table_name")
     assert_equal '"schema_name"."table.name"', @connection.quote_table_name('schema_name."table.name"')
     assert_equal '"schema.name"."table_name"', @connection.quote_table_name('"schema.name".table_name')
     assert_equal '"schema.name"."table.name"', @connection.quote_table_name('"schema.name"."table.name"')
@@ -287,7 +287,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_raise_on_unquoted_schema_name
     assert_raises(ActiveRecord::StatementInvalid) do
-      with_schema_search_path '$user,public'
+      with_schema_search_path "$user,public"
     end
   end
 
@@ -307,7 +307,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
       assert @connection.index_name_exists?(TABLE_NAME, INDEX_D_NAME, true)
       assert @connection.index_name_exists?(TABLE_NAME, INDEX_E_NAME, true)
       assert @connection.index_name_exists?(TABLE_NAME, INDEX_E_NAME, true)
-      assert_not @connection.index_name_exists?(TABLE_NAME, 'missing_index', true)
+      assert_not @connection.index_name_exists?(TABLE_NAME, "missing_index", true)
     end
   end
 
@@ -356,13 +356,13 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
       %(#{SCHEMA_NAME}."#{PK_TABLE_NAME}"),
       %(#{SCHEMA_NAME}.#{PK_TABLE_NAME})
     ].each do |given|
-      assert_equal 'id', @connection.primary_key(given), "primary key should be found when table referenced as #{given}"
+      assert_equal "id", @connection.primary_key(given), "primary key should be found when table referenced as #{given}"
     end
   end
 
   def test_primary_key_assuming_schema_search_path
     with_schema_search_path(SCHEMA_NAME) do
-      assert_equal 'id', @connection.primary_key(PK_TABLE_NAME), "primary key should be found"
+      assert_equal "id", @connection.primary_key(PK_TABLE_NAME), "primary key should be found"
     end
   end
 
@@ -381,7 +381,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
       %("#{SCHEMA_NAME}"."#{UNMATCHED_PK_TABLE_NAME}")
     ].each do |given|
       pk, seq = @connection.pk_and_sequence_for(given)
-      assert_equal 'id', pk, "primary key should be found when table referenced as #{given}"
+      assert_equal "id", pk, "primary key should be found when table referenced as #{given}"
       assert_equal pg_name.new(SCHEMA_NAME, "#{PK_TABLE_NAME}_id_seq"), seq, "sequence name should be found when table referenced as #{given}" if given == %("#{SCHEMA_NAME}"."#{PK_TABLE_NAME}")
       assert_equal pg_name.new(SCHEMA_NAME, UNMATCHED_SEQUENCE_NAME), seq, "sequence name should be found when table referenced as #{given}" if given ==  %("#{SCHEMA_NAME}"."#{UNMATCHED_PK_TABLE_NAME}")
     end
@@ -389,10 +389,10 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_current_schema
     {
-      %('$user',public)                        => 'public',
+      %('$user',public)                        => "public",
       SCHEMA_NAME                              => SCHEMA_NAME,
       %(#{SCHEMA2_NAME},#{SCHEMA_NAME},public) => SCHEMA2_NAME,
-      %(public,#{SCHEMA2_NAME},#{SCHEMA_NAME}) => 'public'
+      %(public,#{SCHEMA2_NAME},#{SCHEMA_NAME}) => "public"
     }.each do |given,expect|
       with_schema_search_path(given) { assert_equal expect, @connection.current_schema }
     end
@@ -414,10 +414,10 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
 
   def test_schema_exists?
     {
-      'public'     => true,
+      "public"     => true,
       SCHEMA_NAME  => true,
       SCHEMA2_NAME => true,
-      'darkside'   => false
+      "darkside"   => false
     }.each do |given,expect|
       assert_equal expect, @connection.schema_exists?(given)
     end
@@ -442,7 +442,7 @@ class SchemaTest < ActiveRecord::PostgreSQLTestCase
   private
     def columns(table_name)
       @connection.send(:column_definitions, table_name).map do |name, type, default|
-        "#{name} #{type}" + (default ? " default #{default}" : '')
+        "#{name} #{type}" + (default ? " default #{default}" : "")
       end
     end
 
diff --git a/activerecord/test/cases/adapters/postgresql/serial_test.rb b/activerecord/test/cases/adapters/postgresql/serial_test.rb
index 8abe064bf1..d711b3b729 100644
--- a/activerecord/test/cases/adapters/postgresql/serial_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/serial_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class PostgresqlSerialTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
diff --git a/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb b/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
index 5aab246c99..eb9978a898 100644
--- a/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/statement_pool_test.rb
@@ -1,4 +1,4 @@
-require 'cases/helper'
+require "cases/helper"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -17,22 +17,22 @@ module ActiveRecord
         if Process.respond_to?(:fork)
           def test_cache_is_per_pid
             cache = StatementPool.new nil, 10
-            cache['foo'] = 'bar'
-            assert_equal 'bar', cache['foo']
+            cache["foo"] = "bar"
+            assert_equal "bar", cache["foo"]
 
             pid = fork {
-              lookup = cache['foo'];
+              lookup = cache["foo"];
               exit!(!lookup)
             }
 
             Process.waitpid pid
-            assert $?.success?, 'process should exit successfully'
+            assert $?.success?, "process should exit successfully"
           end
         end
 
         def test_dealloc_does_not_raise_on_inactive_connection
           cache = StatementPool.new InactivePGconn.new, 10
-          cache['foo'] = 'bar'
+          cache["foo"] = "bar"
           assert_nothing_raised { cache.clear }
         end
       end
diff --git a/activerecord/test/cases/adapters/postgresql/timestamp_test.rb b/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
index 4c4866b46b..ad290626ee 100644
--- a/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/timestamp_test.rb
@@ -1,6 +1,6 @@
-require 'cases/helper'
-require 'models/developer'
-require 'models/topic'
+require "cases/helper"
+require "models/developer"
+require "models/topic"
 
 class PostgresqlTimestampTest < ActiveRecord::PostgreSQLTestCase
   class PostgresqlTimestampWithZone < ActiveRecord::Base; end
@@ -32,7 +32,7 @@ class PostgresqlTimestampTest < ActiveRecord::PostgreSQLTestCase
     with_timezone_config default: :local, aware_attributes: false do
       @connection.reconnect!
       # make sure to use a non-UTC time zone
-      @connection.execute("SET time zone 'America/Jamaica'", 'SCHEMA')
+      @connection.execute("SET time zone 'America/Jamaica'", "SCHEMA")
 
       timestamp = PostgresqlTimestampWithZone.find(1)
       assert_equal Time.utc(2010,1,1, 11,0,0), timestamp.time
@@ -54,19 +54,19 @@ class PostgresqlTimestampFixtureTest < ActiveRecord::PostgreSQLTestCase
 
   def test_load_infinity_and_beyond
     d = Developer.find_by_sql("select 'infinity'::timestamp as updated_at")
-    assert d.first.updated_at.infinite?, 'timestamp should be infinite'
+    assert d.first.updated_at.infinite?, "timestamp should be infinite"
 
     d = Developer.find_by_sql("select '-infinity'::timestamp as updated_at")
     time = d.first.updated_at
-    assert time.infinite?, 'timestamp should be infinite'
+    assert time.infinite?, "timestamp should be infinite"
     assert_operator time, :<, 0
   end
 
   def test_save_infinity_and_beyond
-    d = Developer.create!(:name => 'aaron', :updated_at => 1.0 / 0.0)
+    d = Developer.create!(:name => "aaron", :updated_at => 1.0 / 0.0)
     assert_equal(1.0 / 0.0, d.updated_at)
 
-    d = Developer.create!(:name => 'aaron', :updated_at => -1.0 / 0.0)
+    d = Developer.create!(:name => "aaron", :updated_at => -1.0 / 0.0)
     assert_equal(-1.0 / 0.0, d.updated_at)
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/transaction_test.rb b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
index 8dea92c785..c5164fc1f8 100644
--- a/activerecord/test/cases/adapters/postgresql/transaction_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
@@ -1,21 +1,21 @@
 require "cases/helper"
-require 'support/connection_helper'
+require "support/connection_helper"
 
 module ActiveRecord
   class PostgresqlTransactionTest < ActiveRecord::PostgreSQLTestCase
     self.use_transactional_tests = false
 
     class Sample < ActiveRecord::Base
-      self.table_name = 'samples'
+      self.table_name = "samples"
     end
 
     setup do
       @connection = ActiveRecord::Base.connection
 
       @connection.transaction do
-        @connection.drop_table 'samples', if_exists: true
-        @connection.create_table('samples') do |t|
-          t.integer 'value'
+        @connection.drop_table "samples", if_exists: true
+        @connection.create_table("samples") do |t|
+          t.integer "value"
         end
       end
 
@@ -23,7 +23,7 @@ module ActiveRecord
     end
 
     teardown do
-      @connection.drop_table 'samples', if_exists: true
+      @connection.drop_table "samples", if_exists: true
     end
 
     test "raises SerializationFailure when a serialization failure occurs" do
@@ -89,7 +89,7 @@ module ActiveRecord
 
     def with_warning_suppression
       log_level = @connection.client_min_messages
-      @connection.client_min_messages = 'error'
+      @connection.client_min_messages = "error"
       yield
       @connection.client_min_messages = log_level
     end
diff --git a/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb b/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
index ea0f0b8fa5..bd45a9daa0 100644
--- a/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/type_lookup_test.rb
@@ -1,4 +1,4 @@
-require 'cases/helper'
+require "cases/helper"
 
 class PostgresqlTypeLookupTest < ActiveRecord::PostgreSQLTestCase
   setup do
@@ -9,8 +9,8 @@ class PostgresqlTypeLookupTest < ActiveRecord::PostgreSQLTestCase
     box_array = @connection.type_map.lookup(1020)
     int_array = @connection.type_map.lookup(1007)
 
-    assert_equal ';', box_array.delimiter
-    assert_equal ',', int_array.delimiter
+    assert_equal ";", box_array.delimiter
+    assert_equal ",", int_array.delimiter
   end
 
   test "array types correctly respect registration of subtypes" do
diff --git a/activerecord/test/cases/adapters/postgresql/utils_test.rb b/activerecord/test/cases/adapters/postgresql/utils_test.rb
index 095c1826e5..70f72dd929 100644
--- a/activerecord/test/cases/adapters/postgresql/utils_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/utils_test.rb
@@ -1,5 +1,5 @@
-require 'cases/helper'
-require 'active_record/connection_adapters/postgresql/utils'
+require "cases/helper"
+require "active_record/connection_adapters/postgresql/utils"
 
 class PostgreSQLUtilsTest < ActiveRecord::PostgreSQLTestCase
   Name = ActiveRecord::ConnectionAdapters::PostgreSQL::Name
@@ -7,14 +7,14 @@ class PostgreSQLUtilsTest < ActiveRecord::PostgreSQLTestCase
 
   def test_extract_schema_qualified_name
     {
-      %(table_name)            => [nil,'table_name'],
-      %("table.name")          => [nil,'table.name'],
+      %(table_name)            => [nil,"table_name"],
+      %("table.name")          => [nil,"table.name"],
       %(schema.table_name)     => %w{schema table_name},
       %("schema".table_name)   => %w{schema table_name},
       %(schema."table_name")   => %w{schema table_name},
       %("schema"."table_name") => %w{schema table_name},
-      %("even spaces".table)   => ['even spaces','table'],
-      %(schema."table.name")   => ['schema', 'table.name']
+      %("even spaces".table)   => ["even spaces","table"],
+      %(schema."table.name")   => ["schema", "table.name"]
     }.each do |given, expect|
       assert_equal Name.new(*expect), extract_schema_qualified_name(given)
     end
diff --git a/activerecord/test/cases/adapters/postgresql/uuid_test.rb b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
index 7628075ad2..2052d3851d 100644
--- a/activerecord/test/cases/adapters/postgresql/uuid_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 module PostgresqlUUIDHelper
   def connection
@@ -20,10 +20,10 @@ class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
   end
 
   setup do
-    enable_extension!('uuid-ossp', connection)
+    enable_extension!("uuid-ossp", connection)
 
     connection.create_table "uuid_data_type" do |t|
-      t.uuid 'guid'
+      t.uuid "guid"
     end
   end
 
@@ -34,13 +34,13 @@ class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
   def test_change_column_default
     @connection.add_column :uuid_data_type, :thingy, :uuid, null: false, default: "uuid_generate_v1()"
     UUIDType.reset_column_information
-    column = UUIDType.columns_hash['thingy']
+    column = UUIDType.columns_hash["thingy"]
     assert_equal "uuid_generate_v1()", column.default_function
 
     @connection.change_column :uuid_data_type, :thingy, :uuid, null: false, default: "uuid_generate_v4()"
 
     UUIDType.reset_column_information
-    column = UUIDType.columns_hash['thingy']
+    column = UUIDType.columns_hash["thingy"]
     assert_equal "uuid_generate_v4()", column.default_function
   ensure
     UUIDType.reset_column_information
@@ -57,46 +57,46 @@ class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
   end
 
   def test_treat_blank_uuid_as_nil
-    UUIDType.create! guid: ''
+    UUIDType.create! guid: ""
     assert_equal(nil, UUIDType.last.guid)
   end
 
   def test_treat_invalid_uuid_as_nil
-    uuid = UUIDType.create! guid: 'foobar'
+    uuid = UUIDType.create! guid: "foobar"
     assert_equal(nil, uuid.guid)
   end
 
   def test_invalid_uuid_dont_modify_before_type_cast
-    uuid = UUIDType.new guid: 'foobar'
-    assert_equal 'foobar', uuid.guid_before_type_cast
+    uuid = UUIDType.new guid: "foobar"
+    assert_equal "foobar", uuid.guid_before_type_cast
   end
 
   def test_acceptable_uuid_regex
     # Valid uuids
-    ['A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11',
-     '{a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11}',
-     'a0eebc999c0b4ef8bb6d6bb9bd380a11',
-     'a0ee-bc99-9c0b-4ef8-bb6d-6bb9-bd38-0a11',
-     '{a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11}',
+    ["A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11",
+     "{a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11}",
+     "a0eebc999c0b4ef8bb6d6bb9bd380a11",
+     "a0ee-bc99-9c0b-4ef8-bb6d-6bb9-bd38-0a11",
+     "{a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11}",
      # The following is not a valid RFC 4122 UUID, but PG doesn't seem to care,
      # so we shouldn't block it either. (Pay attention to "fb6d" – the "f" here
      # is invalid – it must be one of 8, 9, A, B, a, b according to the spec.)
-     '{a0eebc99-9c0b-4ef8-fb6d-6bb9bd380a11}',
+     "{a0eebc99-9c0b-4ef8-fb6d-6bb9bd380a11}",
     ].each do |valid_uuid|
       uuid = UUIDType.new guid: valid_uuid
       assert_not_nil uuid.guid
     end
 
     # Invalid uuids
-    [['A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11'],
+    [["A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11"],
      Hash.new,
      0,
      0.0,
      true,
-     'Z0000C99-9C0B-4EF8-BB6D-6BB9BD380A11',
-     'a0eebc999r0b4ef8ab6d6bb9bd380a11',
-     'a0ee-bc99------4ef8-bb6d-6bb9-bd38-0a11',
-     '{a0eebc99-bb6d6bb9-bd380a11}'].each do |invalid_uuid|
+     "Z0000C99-9C0B-4EF8-BB6D-6BB9BD380A11",
+     "a0eebc999r0b4ef8ab6d6bb9bd380a11",
+     "a0ee-bc99------4ef8-bb6d-6bb9-bd38-0a11",
+     "{a0eebc99-bb6d6bb9-bd380a11}"].each do |invalid_uuid|
       uuid = UUIDType.new guid: invalid_uuid
       assert_nil uuid.guid
     end
@@ -142,13 +142,13 @@ class PostgresqlUUIDGenerationTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
 
   class UUID < ActiveRecord::Base
-    self.table_name = 'pg_uuids'
+    self.table_name = "pg_uuids"
   end
 
   setup do
-    connection.create_table('pg_uuids', id: :uuid, default: 'uuid_generate_v1()') do |t|
-      t.string 'name'
-      t.uuid 'other_uuid', default: 'uuid_generate_v4()'
+    connection.create_table("pg_uuids", id: :uuid, default: "uuid_generate_v1()") do |t|
+      t.string "name"
+      t.uuid "other_uuid", default: "uuid_generate_v4()"
     end
 
     # Create custom PostgreSQL function to generate UUIDs
@@ -160,21 +160,21 @@ class PostgresqlUUIDGenerationTest < ActiveRecord::PostgreSQLTestCase
     SQL
 
     # Create such a table with custom function as default value generator
-    connection.create_table('pg_uuids_2', id: :uuid, default: 'my_uuid_generator()') do |t|
-      t.string 'name'
-      t.uuid 'other_uuid_2', default: 'my_uuid_generator()'
+    connection.create_table("pg_uuids_2", id: :uuid, default: "my_uuid_generator()") do |t|
+      t.string "name"
+      t.uuid "other_uuid_2", default: "my_uuid_generator()"
     end
   end
 
   teardown do
     drop_table "pg_uuids"
-    drop_table 'pg_uuids_2'
-    connection.execute 'DROP FUNCTION IF EXISTS my_uuid_generator();'
+    drop_table "pg_uuids_2"
+    connection.execute "DROP FUNCTION IF EXISTS my_uuid_generator();"
   end
 
   if ActiveRecord::Base.connection.supports_extensions?
     def test_id_is_uuid
-      assert_equal :uuid, UUID.columns_hash['id'].type
+      assert_equal :uuid, UUID.columns_hash["id"].type
       assert UUID.primary_key
     end
 
@@ -190,8 +190,8 @@ class PostgresqlUUIDGenerationTest < ActiveRecord::PostgreSQLTestCase
     end
 
     def test_pk_and_sequence_for_uuid_primary_key
-      pk, seq = connection.pk_and_sequence_for('pg_uuids')
-      assert_equal 'id', pk
+      pk, seq = connection.pk_and_sequence_for("pg_uuids")
+      assert_equal "id", pk
       assert_equal nil, seq
     end
 
@@ -214,9 +214,9 @@ class PostgresqlUUIDTestNilDefault < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
 
   setup do
-    connection.create_table('pg_uuids', id: false) do |t|
+    connection.create_table("pg_uuids", id: false) do |t|
       t.primary_key :id, :uuid, default: nil
-      t.string 'name'
+      t.string "name"
     end
   end
 
@@ -244,23 +244,23 @@ class PostgresqlUUIDTestInverseOf < ActiveRecord::PostgreSQLTestCase
   include PostgresqlUUIDHelper
 
   class UuidPost < ActiveRecord::Base
-    self.table_name = 'pg_uuid_posts'
+    self.table_name = "pg_uuid_posts"
     has_many :uuid_comments, inverse_of: :uuid_post
   end
 
   class UuidComment < ActiveRecord::Base
-    self.table_name = 'pg_uuid_comments'
+    self.table_name = "pg_uuid_comments"
     belongs_to :uuid_post
   end
 
   setup do
     connection.transaction do
-      connection.create_table('pg_uuid_posts', id: :uuid) do |t|
-        t.string 'title'
+      connection.create_table("pg_uuid_posts", id: :uuid) do |t|
+        t.string "title"
       end
-      connection.create_table('pg_uuid_comments', id: :uuid) do |t|
+      connection.create_table("pg_uuid_comments", id: :uuid) do |t|
         t.references :uuid_post, type: :uuid
-        t.string 'content'
+        t.string "content"
       end
     end
   end
diff --git a/activerecord/test/cases/adapters/postgresql/xml_test.rb b/activerecord/test/cases/adapters/postgresql/xml_test.rb
index add32699fa..dc80834b21 100644
--- a/activerecord/test/cases/adapters/postgresql/xml_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/xml_test.rb
@@ -1,28 +1,28 @@
-require 'cases/helper'
-require 'support/schema_dumping_helper'
+require "cases/helper"
+require "support/schema_dumping_helper"
 
 class PostgresqlXMLTest < ActiveRecord::PostgreSQLTestCase
   include SchemaDumpingHelper
   class XmlDataType < ActiveRecord::Base
-    self.table_name = 'xml_data_type'
+    self.table_name = "xml_data_type"
   end
 
   def setup
     @connection = ActiveRecord::Base.connection
     begin
       @connection.transaction do
-        @connection.create_table('xml_data_type') do |t|
-          t.xml 'payload'
+        @connection.create_table("xml_data_type") do |t|
+          t.xml "payload"
         end
       end
     rescue ActiveRecord::StatementInvalid
       skip "do not test on PG without xml"
     end
-    @column = XmlDataType.columns_hash['payload']
+    @column = XmlDataType.columns_hash["payload"]
   end
 
   teardown do
-    @connection.drop_table 'xml_data_type', if_exists: true
+    @connection.drop_table "xml_data_type", if_exists: true
   end
 
   def test_column
diff --git a/activerecord/test/cases/adapters/sqlite3/collation_test.rb b/activerecord/test/cases/adapters/sqlite3/collation_test.rb
index 58a9469ce5..28e8f12c18 100644
--- a/activerecord/test/cases/adapters/sqlite3/collation_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/collation_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'support/schema_dumping_helper'
+require "support/schema_dumping_helper"
 
 class SQLite3CollationTest < ActiveRecord::SQLite3TestCase
   include SchemaDumpingHelper
@@ -7,8 +7,8 @@ class SQLite3CollationTest < ActiveRecord::SQLite3TestCase
   def setup
     @connection = ActiveRecord::Base.connection
     @connection.create_table :collation_table_sqlite3, force: true do |t|
-      t.string :string_nocase, collation: 'NOCASE'
-      t.text :text_rtrim, collation: 'RTRIM'
+      t.string :string_nocase, collation: "NOCASE"
+      t.text :text_rtrim, collation: "RTRIM"
     end
   end
 
@@ -17,32 +17,32 @@ class SQLite3CollationTest < ActiveRecord::SQLite3TestCase
   end
 
   test "string column with collation" do
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'string_nocase' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "string_nocase" }
     assert_equal :string, column.type
-    assert_equal 'NOCASE', column.collation
+    assert_equal "NOCASE", column.collation
   end
 
   test "text column with collation" do
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'text_rtrim' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "text_rtrim" }
     assert_equal :text, column.type
-    assert_equal 'RTRIM', column.collation
+    assert_equal "RTRIM", column.collation
   end
 
   test "add column with collation" do
-    @connection.add_column :collation_table_sqlite3, :title, :string, collation: 'RTRIM'
+    @connection.add_column :collation_table_sqlite3, :title, :string, collation: "RTRIM"
 
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'title' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "title" }
     assert_equal :string, column.type
-    assert_equal 'RTRIM', column.collation
+    assert_equal "RTRIM", column.collation
   end
 
   test "change column with collation" do
     @connection.add_column :collation_table_sqlite3, :description, :string
-    @connection.change_column :collation_table_sqlite3, :description, :text, collation: 'RTRIM'
+    @connection.change_column :collation_table_sqlite3, :description, :text, collation: "RTRIM"
 
-    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == 'description' }
+    column = @connection.columns(:collation_table_sqlite3).find { |c| c.name == "description" }
     assert_equal :text, column.type
-    assert_equal 'RTRIM', column.collation
+    assert_equal "RTRIM", column.collation
   end
 
   test "schema dump includes collation" do
diff --git a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
index 34e3b2e023..81058064e2 100644
--- a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
@@ -10,7 +10,7 @@ class CopyTableTest < ActiveRecord::SQLite3TestCase
     end
   end
 
-  def test_copy_table(from = 'customers', to = 'customers2', options = {})
+  def test_copy_table(from = "customers", to = "customers2", options = {})
     assert_nothing_raised {copy_table(from, to, options)}
     assert_equal row_count(from), row_count(to)
 
@@ -24,39 +24,39 @@ class CopyTableTest < ActiveRecord::SQLite3TestCase
   end
 
   def test_copy_table_renaming_column
-    test_copy_table('customers', 'customers2',
-        :rename => {'name' => 'person_name'}) do |from, to, options|
-      expected = column_values(from, 'name')
-      assert_equal expected, column_values(to, 'person_name')
+    test_copy_table("customers", "customers2",
+        :rename => {"name" => "person_name"}) do |from, to, options|
+      expected = column_values(from, "name")
+      assert_equal expected, column_values(to, "person_name")
       assert expected.any?, "No values in table: #{expected.inspect}"
     end
   end
 
   def test_copy_table_allows_to_pass_options_to_create_table
-    @connection.create_table('blocker_table')
-    test_copy_table('customers', 'blocker_table', force: true)
+    @connection.create_table("blocker_table")
+    test_copy_table("customers", "blocker_table", force: true)
   end
 
   def test_copy_table_with_index
-    test_copy_table('comments', 'comments_with_index') do
-      @connection.add_index('comments_with_index', ['post_id', 'type'])
-      test_copy_table('comments_with_index', 'comments_with_index2') do
-        assert_equal table_indexes_without_name('comments_with_index'),
-                     table_indexes_without_name('comments_with_index2')
+    test_copy_table("comments", "comments_with_index") do
+      @connection.add_index("comments_with_index", ["post_id", "type"])
+      test_copy_table("comments_with_index", "comments_with_index2") do
+        assert_equal table_indexes_without_name("comments_with_index"),
+                     table_indexes_without_name("comments_with_index2")
       end
     end
   end
 
   def test_copy_table_without_primary_key
-    test_copy_table('developers_projects', 'programmers_projects') do
-      assert_nil @connection.primary_key('programmers_projects')
+    test_copy_table("developers_projects", "programmers_projects") do
+      assert_nil @connection.primary_key("programmers_projects")
     end
   end
 
   def test_copy_table_with_id_col_that_is_not_primary_key
-    test_copy_table('goofy_string_id', 'goofy_string_id2') do
-      original_id = @connection.columns('goofy_string_id').detect{|col| col.name == 'id' }
-      copied_id = @connection.columns('goofy_string_id2').detect{|col| col.name == 'id' }
+    test_copy_table("goofy_string_id", "goofy_string_id2") do
+      original_id = @connection.columns("goofy_string_id").detect{|col| col.name == "id" }
+      copied_id = @connection.columns("goofy_string_id2").detect{|col| col.name == "id" }
       assert_equal original_id.type, copied_id.type
       assert_equal original_id.sql_type, copied_id.sql_type
       assert_equal original_id.limit, copied_id.limit
@@ -64,15 +64,15 @@ class CopyTableTest < ActiveRecord::SQLite3TestCase
   end
 
   def test_copy_table_with_unconventional_primary_key
-    test_copy_table('owners', 'owners_unconventional') do
-      original_pk = @connection.primary_key('owners')
-      copied_pk = @connection.primary_key('owners_unconventional')
+    test_copy_table("owners", "owners_unconventional") do
+      original_pk = @connection.primary_key("owners")
+      copied_pk = @connection.primary_key("owners_unconventional")
       assert_equal original_pk, copied_pk
     end
   end
 
   def test_copy_table_with_binary_column
-    test_copy_table 'binaries', 'binaries2'
+    test_copy_table "binaries", "binaries2"
   end
 
 protected
@@ -81,7 +81,7 @@ protected
   end
 
   def column_names(table)
-    @connection.table_structure(table).map {|column| column['name']}
+    @connection.table_structure(table).map {|column| column["name"]}
   end
 
   def column_values(table, column)
@@ -93,6 +93,6 @@ protected
   end
 
   def row_count(table)
-    @connection.select_one("SELECT COUNT(*) AS count FROM #{table}")['count']
+    @connection.select_one("SELECT COUNT(*) AS count FROM #{table}")["count"]
   end
 end
diff --git a/activerecord/test/cases/adapters/sqlite3/explain_test.rb b/activerecord/test/cases/adapters/sqlite3/explain_test.rb
index 4d25bd615d..128acb79cf 100644
--- a/activerecord/test/cases/adapters/sqlite3/explain_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/explain_test.rb
@@ -1,6 +1,6 @@
 require "cases/helper"
-require 'models/developer'
-require 'models/computer'
+require "models/developer"
+require "models/computer"
 
 class SQLite3ExplainTest < ActiveRecord::SQLite3TestCase
   fixtures :developers
diff --git a/activerecord/test/cases/adapters/sqlite3/quoting_test.rb b/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
index fe2425b845..80a37e83ff 100644
--- a/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/quoting_test.rb
@@ -1,7 +1,7 @@
 require "cases/helper"
-require 'bigdecimal'
-require 'yaml'
-require 'securerandom'
+require "bigdecimal"
+require "yaml"
+require "securerandom"
 
 class SQLite3QuotingTest < ActiveRecord::SQLite3TestCase
   def setup
@@ -16,7 +16,7 @@ class SQLite3QuotingTest < ActiveRecord::SQLite3TestCase
   end
 
   def test_type_cast_symbol
-    assert_equal 'foo', @conn.type_cast(:foo)
+    assert_equal "foo", @conn.type_cast(:foo)
   end
 
   def test_type_cast_date
@@ -41,15 +41,15 @@ class SQLite3QuotingTest < ActiveRecord::SQLite3TestCase
   end
 
   def test_type_cast_true
-    assert_equal 't', @conn.type_cast(true)
+    assert_equal "t", @conn.type_cast(true)
   end
 
   def test_type_cast_false
-    assert_equal 'f', @conn.type_cast(false)
+    assert_equal "f", @conn.type_cast(false)
   end
 
   def test_type_cast_bigdecimal
-    bd = BigDecimal.new '10.0'
+    bd = BigDecimal.new "10.0"
     assert_equal bd.to_f, @conn.type_cast(bd)
   end
 
@@ -79,7 +79,7 @@ class SQLite3QuotingTest < ActiveRecord::SQLite3TestCase
   end
 
   def test_quoting_binary_strings
-    value = "hello".encode('ascii-8bit')
+    value = "hello".encode("ascii-8bit")
     type = ActiveRecord::Type::String.new
 
     assert_equal "'hello'", @conn.quote(type.serialize(value))
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
index bbc9f978bf..7edec0cb47 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
@@ -1,7 +1,7 @@
 require "cases/helper"
-require 'models/owner'
-require 'tempfile'
-require 'support/ddl_helper'
+require "models/owner"
+require "tempfile"
+require "support/ddl_helper"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -14,22 +14,22 @@ module ActiveRecord
       end
 
       def setup
-        @conn = Base.sqlite3_connection database: ':memory:',
-                                        adapter: 'sqlite3',
+        @conn = Base.sqlite3_connection database: ":memory:",
+                                        adapter: "sqlite3",
                                         timeout: 100
       end
 
       def test_bad_connection
         assert_raise ActiveRecord::NoDatabaseError do
           connection = ActiveRecord::Base.sqlite3_connection(adapter: "sqlite3", database: "/tmp/should/_not/_exist/-cinco-dog.db")
-          connection.drop_table 'ex', if_exists: true
+          connection.drop_table "ex", if_exists: true
         end
       end
 
       unless in_memory_db?
         def test_connect_with_url
           original_connection = ActiveRecord::Base.remove_connection
-          tf = Tempfile.open 'whatever'
+          tf = Tempfile.open "whatever"
           url = "sqlite3:#{tf.path}"
           ActiveRecord::Base.establish_connection(url)
           assert ActiveRecord::Base.connection
@@ -51,7 +51,7 @@ module ActiveRecord
 
       def test_valid_column
         with_example_table do
-          column = @conn.columns('ex').find { |col| col.name == 'id' }
+          column = @conn.columns("ex").find { |col| col.name == "id" }
           assert @conn.valid_type?(column.type)
         end
       end
@@ -66,9 +66,9 @@ module ActiveRecord
       end
 
       def test_column_types
-        owner = Owner.create!(name: "hello".encode('ascii-8bit'))
+        owner = Owner.create!(name: "hello".encode("ascii-8bit"))
         owner.reload
-        select = Owner.columns.map { |c| "typeof(#{c.name})" }.join ', '
+        select = Owner.columns.map { |c| "typeof(#{c.name})" }.join ", "
         result = Owner.connection.exec_query <<-esql
           SELECT #{select}
           FROM   #{Owner.table_name}
@@ -83,10 +83,10 @@ module ActiveRecord
       def test_exec_insert
         with_example_table do
           vals = [Relation::QueryAttribute.new("number", 10, Type::Value.new)]
-          @conn.exec_insert('insert into ex (number) VALUES (?)', 'SQL', vals)
+          @conn.exec_insert("insert into ex (number) VALUES (?)", "SQL", vals)
 
           result = @conn.exec_query(
-            'select number from ex where number = ?', 'SQL', vals)
+            "select number from ex where number = ?", "SQL", vals)
 
           assert_equal 1, result.rows.length
           assert_equal 10, result.rows.first.first
@@ -94,8 +94,8 @@ module ActiveRecord
       end
 
       def test_primary_key_returns_nil_for_no_pk
-        with_example_table 'id int, data string' do
-          assert_nil @conn.primary_key('ex')
+        with_example_table "id int, data string" do
+          assert_nil @conn.primary_key("ex")
         end
       end
 
@@ -107,69 +107,69 @@ module ActiveRecord
 
       def test_bad_timeout
         assert_raises(TypeError) do
-          Base.sqlite3_connection database: ':memory:',
-                                  adapter: 'sqlite3',
-                                  timeout: 'usa'
+          Base.sqlite3_connection database: ":memory:",
+                                  adapter: "sqlite3",
+                                  timeout: "usa"
         end
       end
 
       # connection is OK with a nil timeout
       def test_nil_timeout
-        conn = Base.sqlite3_connection database: ':memory:',
-                                       adapter: 'sqlite3',
+        conn = Base.sqlite3_connection database: ":memory:",
+                                       adapter: "sqlite3",
                                        timeout: nil
-        assert conn, 'made a connection'
+        assert conn, "made a connection"
       end
 
       def test_connect
-        assert @conn, 'should have connection'
+        assert @conn, "should have connection"
       end
 
       # sqlite3 defaults to UTF-8 encoding
       def test_encoding
-        assert_equal 'UTF-8', @conn.encoding
+        assert_equal "UTF-8", @conn.encoding
       end
 
       def test_exec_no_binds
-        with_example_table 'id int, data string' do
-          result = @conn.exec_query('SELECT id, data FROM ex')
+        with_example_table "id int, data string" do
+          result = @conn.exec_query("SELECT id, data FROM ex")
           assert_equal 0, result.rows.length
           assert_equal 2, result.columns.length
           assert_equal %w{ id data }, result.columns
 
           @conn.exec_query('INSERT INTO ex (id, data) VALUES (1, "foo")')
-          result = @conn.exec_query('SELECT id, data FROM ex')
+          result = @conn.exec_query("SELECT id, data FROM ex")
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
       def test_exec_query_with_binds
-        with_example_table 'id int, data string' do
+        with_example_table "id int, data string" do
           @conn.exec_query('INSERT INTO ex (id, data) VALUES (1, "foo")')
           result = @conn.exec_query(
-            'SELECT id, data FROM ex WHERE id = ?', nil, [Relation::QueryAttribute.new(nil, 1, Type::Value.new)])
+            "SELECT id, data FROM ex WHERE id = ?", nil, [Relation::QueryAttribute.new(nil, 1, Type::Value.new)])
 
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
       def test_exec_query_typecasts_bind_vals
-        with_example_table 'id int, data string' do
+        with_example_table "id int, data string" do
           @conn.exec_query('INSERT INTO ex (id, data) VALUES (1, "foo")')
 
           result = @conn.exec_query(
-            'SELECT id, data FROM ex WHERE id = ?', nil, [Relation::QueryAttribute.new("id", "1-fuu", Type::Integer.new)])
+            "SELECT id, data FROM ex WHERE id = ?", nil, [Relation::QueryAttribute.new("id", "1-fuu", Type::Integer.new)])
 
           assert_equal 1, result.rows.length
           assert_equal 2, result.columns.length
 
-          assert_equal [[1, 'foo']], result.rows
+          assert_equal [[1, "foo"]], result.rows
         end
       end
 
@@ -182,15 +182,15 @@ module ActiveRecord
           )
         eosql
         str = "\x80".force_encoding("ASCII-8BIT")
-        binary = DualEncoding.new name: 'いただきます！', data: str
+        binary = DualEncoding.new name: "いただきます！", data: str
         binary.save!
         assert_equal str, binary.data
       ensure
-        DualEncoding.connection.drop_table 'dual_encodings', if_exists: true
+        DualEncoding.connection.drop_table "dual_encodings", if_exists: true
       end
 
       def test_type_cast_should_not_mutate_encoding
-        name  = 'hello'.force_encoding(Encoding::ASCII_8BIT)
+        name  = "hello".force_encoding(Encoding::ASCII_8BIT)
         Owner.create(name: name)
         assert_equal Encoding::ASCII_8BIT, name.encoding
       ensure
@@ -204,8 +204,8 @@ module ActiveRecord
           assert_equal 1, records.length
 
           record = records.first
-          assert_equal 10, record['number']
-          assert_equal 1, record['id']
+          assert_equal 10, record["number"]
+          assert_equal 1, record["id"]
         end
       end
 
@@ -226,7 +226,7 @@ module ActiveRecord
       def test_insert_id_value_returned
         with_example_table do
           sql = "INSERT INTO ex (number) VALUES (10)"
-          idval = 'vuvuzela'
+          idval = "vuvuzela"
           id = @conn.insert(sql, nil, nil, idval)
           assert_equal idval, id
         end
@@ -237,7 +237,7 @@ module ActiveRecord
           2.times do |i|
             @conn.create "INSERT INTO ex (number) VALUES (#{i})"
           end
-          rows = @conn.select_rows 'select number, id from ex'
+          rows = @conn.select_rows "select number, id from ex"
           assert_equal [[0, 1], [1, 2]], rows
         end
       end
@@ -254,7 +254,7 @@ module ActiveRecord
 
       def test_transaction
         with_example_table do
-          count_sql = 'select count(*) from ex'
+          count_sql = "select count(*) from ex"
 
           @conn.begin_db_transaction
           @conn.create "INSERT INTO ex (number) VALUES (10)"
@@ -268,7 +268,7 @@ module ActiveRecord
       def test_tables
         with_example_table do
           ActiveSupport::Deprecation.silence { assert_equal %w{ ex }, @conn.tables }
-          with_example_table 'id integer PRIMARY KEY AUTOINCREMENT, number integer', 'people' do
+          with_example_table "id integer PRIMARY KEY AUTOINCREMENT, number integer", "people" do
             ActiveSupport::Deprecation.silence { assert_equal %w{ ex people }.sort, @conn.tables.sort }
           end
         end
@@ -279,17 +279,17 @@ module ActiveRecord
           SELECT name FROM sqlite_master
           WHERE type IN ('table','view') AND name <> 'sqlite_sequence'
         SQL
-        assert_logged [[sql.squish, 'SCHEMA', []]] do
+        assert_logged [[sql.squish, "SCHEMA", []]] do
           ActiveSupport::Deprecation.silence do
-            @conn.tables('hello')
+            @conn.tables("hello")
           end
         end
       end
 
       def test_indexes_logs_name
         with_example_table do
-          assert_logged [["PRAGMA index_list(\"ex\")", 'SCHEMA', []]] do
-            @conn.indexes('ex', 'hello')
+          assert_logged [["PRAGMA index_list(\"ex\")", "SCHEMA", []]] do
+            @conn.indexes("ex", "hello")
           end
         end
       end
@@ -300,9 +300,9 @@ module ActiveRecord
             SELECT name FROM sqlite_master
             WHERE type IN ('table','view') AND name <> 'sqlite_sequence' AND name = 'ex'
           SQL
-          assert_logged [[sql.squish, 'SCHEMA', []]] do
+          assert_logged [[sql.squish, "SCHEMA", []]] do
             ActiveSupport::Deprecation.silence do
-              assert @conn.table_exists?('ex')
+              assert @conn.table_exists?("ex")
             end
           end
         end
@@ -310,7 +310,7 @@ module ActiveRecord
 
       def test_columns
         with_example_table do
-          columns = @conn.columns('ex').sort_by(&:name)
+          columns = @conn.columns("ex").sort_by(&:name)
           assert_equal 2, columns.length
           assert_equal %w{ id number }.sort, columns.map(&:name)
           assert_equal [nil, nil], columns.map(&:default)
@@ -319,17 +319,17 @@ module ActiveRecord
       end
 
       def test_columns_with_default
-        with_example_table 'id integer PRIMARY KEY AUTOINCREMENT, number integer default 10' do
-          column = @conn.columns('ex').find { |x|
-            x.name == 'number'
+        with_example_table "id integer PRIMARY KEY AUTOINCREMENT, number integer default 10" do
+          column = @conn.columns("ex").find { |x|
+            x.name == "number"
           }
-          assert_equal '10', column.default
+          assert_equal "10", column.default
         end
       end
 
       def test_columns_with_not_null
-        with_example_table 'id integer PRIMARY KEY AUTOINCREMENT, number integer not null' do
-          column = @conn.columns('ex').find { |x| x.name == 'number' }
+        with_example_table "id integer PRIMARY KEY AUTOINCREMENT, number integer not null" do
+          column = @conn.columns("ex").find { |x| x.name == "number" }
           assert_not column.null, "column should not be null"
         end
       end
@@ -337,59 +337,59 @@ module ActiveRecord
       def test_indexes_logs
         with_example_table do
           assert_logged [["PRAGMA index_list(\"ex\")", "SCHEMA", []]] do
-            @conn.indexes('ex')
+            @conn.indexes("ex")
           end
         end
       end
 
       def test_no_indexes
-        assert_equal [], @conn.indexes('items')
+        assert_equal [], @conn.indexes("items")
       end
 
       def test_index
         with_example_table do
-          @conn.add_index 'ex', 'id', unique: true, name: 'fun'
-          index = @conn.indexes('ex').find { |idx| idx.name == 'fun' }
+          @conn.add_index "ex", "id", unique: true, name: "fun"
+          index = @conn.indexes("ex").find { |idx| idx.name == "fun" }
 
-          assert_equal 'ex', index.table
-          assert index.unique, 'index is unique'
-          assert_equal ['id'], index.columns
+          assert_equal "ex", index.table
+          assert index.unique, "index is unique"
+          assert_equal ["id"], index.columns
         end
       end
 
       def test_non_unique_index
         with_example_table do
-          @conn.add_index 'ex', 'id', name: 'fun'
-          index = @conn.indexes('ex').find { |idx| idx.name == 'fun' }
-          assert_not index.unique, 'index is not unique'
+          @conn.add_index "ex", "id", name: "fun"
+          index = @conn.indexes("ex").find { |idx| idx.name == "fun" }
+          assert_not index.unique, "index is not unique"
         end
       end
 
       def test_compound_index
         with_example_table do
-          @conn.add_index 'ex', %w{ id number }, name: 'fun'
-          index = @conn.indexes('ex').find { |idx| idx.name == 'fun' }
+          @conn.add_index "ex", %w{ id number }, name: "fun"
+          index = @conn.indexes("ex").find { |idx| idx.name == "fun" }
           assert_equal %w{ id number }.sort, index.columns.sort
         end
       end
 
       def test_primary_key
         with_example_table do
-          assert_equal 'id', @conn.primary_key('ex')
-          with_example_table 'internet integer PRIMARY KEY AUTOINCREMENT, number integer not null', 'foos' do
-            assert_equal 'internet', @conn.primary_key('foos')
+          assert_equal "id", @conn.primary_key("ex")
+          with_example_table "internet integer PRIMARY KEY AUTOINCREMENT, number integer not null", "foos" do
+            assert_equal "internet", @conn.primary_key("foos")
           end
         end
       end
 
       def test_no_primary_key
-        with_example_table 'number integer not null' do
-          assert_nil @conn.primary_key('ex')
+        with_example_table "number integer not null" do
+          assert_nil @conn.primary_key("ex")
         end
       end
 
       def test_supports_extensions
-        assert_not @conn.supports_extensions?, 'does not support extensions'
+        assert_not @conn.supports_extensions?, "does not support extensions"
       end
 
       def test_respond_to_enable_extension
@@ -402,15 +402,15 @@ module ActiveRecord
 
       def test_statement_closed
         db = ::SQLite3::Database.new(ActiveRecord::Base.
-                                   configurations['arunit']['database'])
+                                   configurations["arunit"]["database"])
         statement = ::SQLite3::Statement.new(db,
-                                           'CREATE TABLE statement_test (number integer not null)')
-        statement.stub(:step, ->{ raise ::SQLite3::BusyException.new('busy') }) do
+                                           "CREATE TABLE statement_test (number integer not null)")
+        statement.stub(:step, ->{ raise ::SQLite3::BusyException.new("busy") }) do
           assert_called(statement, :columns, returns: []) do
             assert_called(statement, :close) do
               ::SQLite3::Statement.stub(:new, statement) do
                 assert_raises ActiveRecord::StatementInvalid do
-                  @conn.exec_query 'select * from statement_test'
+                  @conn.exec_query "select * from statement_test"
                 end
               end
             end
@@ -422,14 +422,14 @@ module ActiveRecord
 
       def assert_logged logs
         subscriber = SQLSubscriber.new
-        subscription = ActiveSupport::Notifications.subscribe('sql.active_record', subscriber)
+        subscription = ActiveSupport::Notifications.subscribe("sql.active_record", subscriber)
         yield
         assert_equal logs, subscriber.logged
       ensure
         ActiveSupport::Notifications.unsubscribe(subscription)
       end
 
-      def with_example_table(definition = nil, table_name = 'ex', &block)
+      def with_example_table(definition = nil, table_name = "ex", &block)
         definition ||= <<-SQL
           id integer PRIMARY KEY AUTOINCREMENT,
           number integer
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
index 9b675b804b..6b1b266372 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_create_folder_test.rb
@@ -1,5 +1,5 @@
 require "cases/helper"
-require 'models/owner'
+require "models/owner"
 
 module ActiveRecord
   module ConnectionAdapters
@@ -9,11 +9,11 @@ module ActiveRecord
           begin
             dir = Pathname.new(dir)
             @conn = Base.sqlite3_connection :database => dir.join("db/foo.sqlite3"),
-                                 :adapter => 'sqlite3',
+                                 :adapter => "sqlite3",
                                  :timeout => 100
 
-            assert Dir.exist? dir.join('db')
-            assert File.exist? dir.join('db/foo.sqlite3')
+            assert Dir.exist? dir.join("db")
+            assert File.exist? dir.join("db/foo.sqlite3")
           ensure
             @conn.disconnect! if @conn
           end
diff --git a/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb b/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
index 24cc6875ab..aebcce3691 100644
--- a/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/statement_pool_test.rb
@@ -1,20 +1,20 @@
-require 'cases/helper'
+require "cases/helper"
 
 class SQLite3StatementPoolTest < ActiveRecord::SQLite3TestCase
   if Process.respond_to?(:fork)
     def test_cache_is_per_pid
 
       cache = ActiveRecord::ConnectionAdapters::SQLite3Adapter::StatementPool.new(10)
-      cache['foo'] = 'bar'
-      assert_equal 'bar', cache['foo']
+      cache["foo"] = "bar"
+      assert_equal "bar", cache["foo"]
 
       pid = fork {
-        lookup = cache['foo'];
+        lookup = cache["foo"];
         exit!(!lookup)
       }
 
       Process.waitpid pid
-      assert $?.success?, 'process should exit successfully'
+      assert $?.success?, "process should exit successfully"
     end
   end
 end