2 files changed, 66 insertions, 1 deletions
diff --git a/activerecord/test/cases/date_time_precision_test.rb b/activerecord/test/cases/date_time_precision_test.rb
index 4602ba6d0d..720f10a9d3 100644
--- a/activerecord/test/cases/date_time_precision_test.rb
+++ b/activerecord/test/cases/date_time_precision_test.rb
@@ -1,7 +1,7 @@
 require 'cases/helper'
 require 'support/schema_dumping_helper'
 
-if mysql_56? || current_adapter?(:PostgreSQLAdapter)
+if ActiveRecord::Base.connection.supports_datetime_with_precision?
 class DateTimePrecisionTest < ActiveRecord::TestCase
   include SchemaDumpingHelper
   self.use_transactional_fixtures = false
diff --git a/activerecord/test/cases/time_precision_test.rb b/activerecord/test/cases/time_precision_test.rb
new file mode 100644
index 0000000000..23422fd50a
--- /dev/null
+++ b/activerecord/test/cases/time_precision_test.rb
@@ -0,0 +1,65 @@
+require 'cases/helper'
+
+if ActiveRecord::Base.connection.supports_datetime_with_precision?
+class TimePrecisionTest < ActiveRecord::TestCase
+  setup do
+    @connection = ActiveRecord::Base.connection
+  end
+
+  teardown do
+    @connection.drop_table :foos, if_exists: true
+  end
+
+  def test_time_data_type_with_precision
+    @connection.create_table(:foos, force: true)
+    @connection.add_column :foos, :start,  :time, precision: 3
+    @connection.add_column :foos, :finish, :time, precision: 6
+    assert_equal 3, activerecord_column_option('foos', 'start',  'precision')
+    assert_equal 6, activerecord_column_option('foos', 'finish', 'precision')
+  end
+
+  def test_passing_precision_to_time_does_not_set_limit
+    @connection.create_table(:foos, force: true) do |t|
+      t.time :start,  precision: 3
+      t.time :finish, precision: 6
+    end
+    assert_nil activerecord_column_option('foos', 'start',  'limit')
+    assert_nil activerecord_column_option('foos', 'finish', 'limit')
+  end
+
+  def test_invalid_time_precision_raises_error
+    assert_raises ActiveRecord::ActiveRecordError do
+      @connection.create_table(:foos, force: true) do |t|
+        t.time :start,  precision: 7
+        t.time :finish, precision: 7
+      end
+    end
+  end
+
+  def test_database_agrees_with_activerecord_about_precision
+    @connection.create_table(:foos, force: true) do |t|
+      t.time :start,  precision: 2
+      t.time :finish, precision: 4
+    end
+    assert_equal 2, database_datetime_precision('foos', 'start')
+    assert_equal 4, database_datetime_precision('foos', 'finish')
+  end
+
+  private
+
+  def database_datetime_precision(table_name, column_name)
+    results = @connection.exec_query("SELECT column_name, datetime_precision FROM information_schema.columns WHERE table_name = '#{table_name}'")
+    result = results.find do |result_hash|
+      result_hash["column_name"] == column_name
+    end
+    result && result["datetime_precision"].to_i
+  end
+
+  def activerecord_column_option(tablename, column_name, option)
+    result = @connection.columns(tablename).find do |column|
+      column.name == column_name
+    end
+    result && result.send(option)
+  end
+end
+end