register OID for PostgreSQL citex datatype [Troy Kruthoff & Lachlan Sylvester]

citext makes it possible to use AR Hash finders for case-insensitive matching as sql UPPER/LOWER functions are not needed.

6 files changed, 89 insertions, 2 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 300c3761f1..2e4f653ea6 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,8 @@
+*   Support for Postgres `citext` data type enabling case-insensitive where
+    values without needing to wrap in UPPER/LOWER sql functions.
+
+    *Troy Kruthoff*, *Lachlan Sylvester*
+
 *   Only save has_one associations if record has changes.
     Previously after save related callbacks, such as `#after_commit`, were triggered when the has_one
     object did not get saved to the db.
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
index 697915f3e9..5d32aaed50 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
@@ -375,6 +375,7 @@ This is not reliable and will be removed in the future.
         register_type 'circle', OID::Text.new
         register_type 'hstore', OID::Hstore.new
         register_type 'json', OID::Json.new
+        register_type 'citext', OID::Text.new
         register_type 'ltree', OID::Text.new
 
         register_type 'cidr', OID::Cidr.new
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index a56ef91d07..f7b053aec6 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -215,6 +215,8 @@ module ActiveRecord
           # Character types
           when /^(?:character varying|bpchar)(?:\(\d+\))?$/
             :string
+          when /^citext(?:\(\d+\))?$/
+            :citext
           # Binary data types
           when 'bytea'
             :binary
@@ -393,6 +395,10 @@ module ActiveRecord
           column name, type, options
         end
 
+        def citext(name, options = {})
+          column(name, 'citext', options)
+        end
+
         def column(name, type = nil, options = {})
           super
           column = self[name]
@@ -441,7 +447,8 @@ module ActiveRecord
         macaddr:     { name: "macaddr" },
         uuid:        { name: "uuid" },
         json:        { name: "json" },
-        ltree:       { name: "ltree" }
+        ltree:       { name: "ltree" },
+        citext:      { name: "citext" }
       }
 
       include Quoting
diff --git a/activerecord/test/cases/adapters/postgresql/citext_test.rb b/activerecord/test/cases/adapters/postgresql/citext_test.rb
new file mode 100644
index 0000000000..89ef46b539
--- /dev/null
+++ b/activerecord/test/cases/adapters/postgresql/citext_test.rb
@@ -0,0 +1,58 @@
+# encoding: utf-8
+
+require 'cases/helper'
+require 'active_record/base'
+require 'active_record/connection_adapters/postgresql_adapter'
+
+class PostgresqlCitextTest < ActiveRecord::TestCase
+  class Citext < ActiveRecord::Base
+    self.table_name = 'citexts'
+  end
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+
+    unless @connection.extension_enabled?('citext')
+      @connection.enable_extension 'citext'
+      @connection.commit_db_transaction
+    end
+
+    @connection.reconnect!
+
+    @connection.transaction do
+      @connection.create_table('citexts') do |t|
+        t.citext 'cival'
+      end
+    end
+    @column = Citext.columns_hash['cival']
+  end
+
+  def teardown
+    @connection.execute 'DROP TABLE IF EXISTS citexts;'
+    @connection.execute 'DROP EXTENSION IF EXISTS citext CASCADE;'
+  end
+
+  def test_citext_enabled
+    assert @connection.extension_enabled?('citext')
+  end
+
+  def test_column_type
+    assert_equal :citext, @column.type
+  end
+
+  def test_column_sql_type
+    assert_equal 'citext', @column.sql_type
+  end
+
+  def test_write
+    x = Citext.new(cival: 'Some CI Text')
+    assert x.save!
+  end
+
+  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)
+  end
+
+end
\ No newline at end of file
diff --git a/activerecord/test/cases/schema_dumper_test.rb b/activerecord/test/cases/schema_dumper_test.rb
index 2748cbdbf4..575eb34a9c 100644
--- a/activerecord/test/cases/schema_dumper_test.rb
+++ b/activerecord/test/cases/schema_dumper_test.rb
@@ -319,6 +319,13 @@ class SchemaDumperTest < ActiveRecord::TestCase
       end
     end
 
+    def test_schema_dump_includes_citext_shorthand_definition
+      output = standard_dump
+      if %r{create_table "postgresql_citext"} =~ output
+        assert_match %r[t.citext "text_citext"], output
+      end
+    end
+
     def test_schema_dump_includes_ltrees_shorthand_definition
       output = standard_dump
       if %r{create_table "postgresql_ltrees"} =~ output
diff --git a/activerecord/test/schema/postgresql_specific_schema.rb b/activerecord/test/schema/postgresql_specific_schema.rb
index a86a188bcf..4fcbf4dbd2 100644
--- a/activerecord/test/schema/postgresql_specific_schema.rb
+++ b/activerecord/test/schema/postgresql_specific_schema.rb
@@ -1,7 +1,7 @@
 ActiveRecord::Schema.define do
 
   %w(postgresql_tsvectors postgresql_hstores postgresql_arrays postgresql_moneys postgresql_numbers postgresql_times postgresql_network_addresses postgresql_bit_strings postgresql_uuids postgresql_ltrees
-      postgresql_oids postgresql_xml_data_type defaults geometrics postgresql_timestamp_with_zones postgresql_partitioned_table postgresql_partitioned_table_parent postgresql_json_data_type).each do |table_name|
+      postgresql_oids postgresql_xml_data_type defaults geometrics postgresql_timestamp_with_zones postgresql_partitioned_table postgresql_partitioned_table_parent postgresql_json_data_type postgresql_citext).each do |table_name|
     execute "DROP TABLE IF EXISTS #{quote_table_name table_name}"
   end
 
@@ -99,6 +99,15 @@ _SQL
 _SQL
   end
 
+  if 't' == select_value("select 'citext'=ANY(select typname from pg_type)")
+  execute <<_SQL
+  CREATE TABLE postgresql_citext (
+    id SERIAL PRIMARY KEY,
+    text_citext citext default ''::citext
+  );
+_SQL
+  end
+
   if 't' == select_value("select 'json'=ANY(select typname from pg_type)")
   execute <<_SQL
   CREATE TABLE postgresql_json_data_type (