1 files changed, 103 insertions, 0 deletions
diff --git a/activerecord/test/cases/time_precision_test.rb b/activerecord/test/cases/time_precision_test.rb
new file mode 100644
index 0000000000..086500de38
--- /dev/null
+++ b/activerecord/test/cases/time_precision_test.rb
@@ -0,0 +1,103 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "support/schema_dumping_helper"
+
+if subsecond_precision_supported?
+  class TimePrecisionTest < ActiveRecord::TestCase
+    include SchemaDumpingHelper
+    self.use_transactional_tests = false
+
+    class Foo < ActiveRecord::Base; end
+
+    setup do
+      @connection = ActiveRecord::Base.connection
+      Foo.reset_column_information
+    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, Foo.columns_hash["start"].precision
+      assert_equal 6, Foo.columns_hash["finish"].precision
+    end
+
+    def test_time_precision_is_truncated_on_assignment
+      @connection.create_table(:foos, force: true)
+      @connection.add_column :foos, :start,  :time, precision: 0
+      @connection.add_column :foos, :finish, :time, precision: 6
+
+      time = ::Time.now.change(nsec: 123456789)
+      foo = Foo.new(start: time, finish: time)
+
+      assert_equal 0, foo.start.nsec
+      assert_equal 123456000, foo.finish.nsec
+
+      foo.save!
+      foo.reload
+
+      assert_equal 0, foo.start.nsec
+      assert_equal 123456000, foo.finish.nsec
+    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 Foo.columns_hash["start"].limit
+      assert_nil Foo.columns_hash["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_formatting_time_according_to_precision
+      @connection.create_table(:foos, force: true) do |t|
+        t.time :start,  precision: 0
+        t.time :finish, precision: 4
+      end
+      time = ::Time.utc(2000, 1, 1, 12, 30, 0, 999999)
+      Foo.create!(start: time, finish: time)
+      assert foo = Foo.find_by(start: time)
+      assert_equal 1, Foo.where(finish: time).count
+      assert_equal time.to_s, foo.start.to_s
+      assert_equal time.to_s, foo.finish.to_s
+      assert_equal 000000, foo.start.usec
+      assert_equal 999900, foo.finish.usec
+    end
+
+    def test_schema_dump_includes_time_precision
+      @connection.create_table(:foos, force: true) do |t|
+        t.time :start,  precision: 4
+        t.time :finish, precision: 6
+      end
+      output = dump_table_schema("foos")
+      assert_match %r{t\.time\s+"start",\s+precision: 4$}, output
+      assert_match %r{t\.time\s+"finish",\s+precision: 6$}, output
+    end
+
+    if current_adapter?(:PostgreSQLAdapter, :SQLServerAdapter)
+      def test_time_precision_with_zero_should_be_dumped
+        @connection.create_table(:foos, force: true) do |t|
+          t.time :start,  precision: 0
+          t.time :finish, precision: 0
+        end
+        output = dump_table_schema("foos")
+        assert_match %r{t\.time\s+"start",\s+precision: 0$}, output
+        assert_match %r{t\.time\s+"finish",\s+precision: 0$}, output
+      end
+    end
+  end
+end