1 files changed, 168 insertions, 0 deletions
diff --git a/activerecord/test/cases/migration/create_join_table_test.rb b/activerecord/test/cases/migration/create_join_table_test.rb
new file mode 100644
index 0000000000..83fb4f9385
--- /dev/null
+++ b/activerecord/test/cases/migration/create_join_table_test.rb
@@ -0,0 +1,168 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveRecord
+  class Migration
+    class CreateJoinTableTest < ActiveRecord::TestCase
+      attr_reader :connection
+
+      def setup
+        super
+        @connection = ActiveRecord::Base.connection
+      end
+
+      teardown do
+        %w(artists_musics musics_videos catalog).each do |table_name|
+          connection.drop_table table_name, if_exists: true
+        end
+      end
+
+      def test_create_join_table
+        connection.create_join_table :artists, :musics
+
+        assert_equal %w(artist_id music_id), connection.columns(:artists_musics).map(&:name).sort
+      end
+
+      def test_create_join_table_set_not_null_by_default
+        connection.create_join_table :artists, :musics
+
+        assert_equal [false, false], connection.columns(:artists_musics).map(&:null)
+      end
+
+      def test_create_join_table_with_strings
+        connection.create_join_table "artists", "musics"
+
+        assert_equal %w(artist_id music_id), connection.columns(:artists_musics).map(&:name).sort
+      end
+
+      def test_create_join_table_with_symbol_and_string
+        connection.create_join_table :artists, "musics"
+
+        assert_equal %w(artist_id music_id), connection.columns(:artists_musics).map(&:name).sort
+      end
+
+      def test_create_join_table_with_the_proper_order
+        connection.create_join_table :videos, :musics
+
+        assert_equal %w(music_id video_id), connection.columns(:musics_videos).map(&:name).sort
+      end
+
+      def test_create_join_table_with_the_table_name
+        connection.create_join_table :artists, :musics, table_name: :catalog
+
+        assert_equal %w(artist_id music_id), connection.columns(:catalog).map(&:name).sort
+      end
+
+      def test_create_join_table_with_the_table_name_as_string
+        connection.create_join_table :artists, :musics, table_name: "catalog"
+
+        assert_equal %w(artist_id music_id), connection.columns(:catalog).map(&:name).sort
+      end
+
+      def test_create_join_table_with_column_options
+        connection.create_join_table :artists, :musics, column_options: { null: true }
+
+        assert_equal [true, true], connection.columns(:artists_musics).map(&:null)
+      end
+
+      def test_create_join_table_without_indexes
+        connection.create_join_table :artists, :musics
+
+        assert_predicate connection.indexes(:artists_musics), :blank?
+      end
+
+      def test_create_join_table_with_index
+        connection.create_join_table :artists, :musics do |t|
+          t.index [:artist_id, :music_id]
+        end
+
+        assert_equal [%w(artist_id music_id)], connection.indexes(:artists_musics).map(&:columns)
+      end
+
+      def test_create_join_table_respects_reference_key_type
+        connection.create_join_table :artists, :musics do |t|
+          t.references :video
+        end
+
+        artist_id, music_id, video_id = connection.columns(:artists_musics).sort_by(&:name)
+
+        assert_equal video_id.sql_type, artist_id.sql_type
+        assert_equal video_id.sql_type, music_id.sql_type
+      end
+
+      def test_drop_join_table
+        connection.create_join_table :artists, :musics
+        connection.drop_join_table :artists, :musics
+
+        assert !connection.table_exists?("artists_musics")
+      end
+
+      def test_drop_join_table_with_strings
+        connection.create_join_table :artists, :musics
+        connection.drop_join_table "artists", "musics"
+
+        assert !connection.table_exists?("artists_musics")
+      end
+
+      def test_drop_join_table_with_the_proper_order
+        connection.create_join_table :videos, :musics
+        connection.drop_join_table :videos, :musics
+
+        assert !connection.table_exists?("musics_videos")
+      end
+
+      def test_drop_join_table_with_the_table_name
+        connection.create_join_table :artists, :musics, table_name: :catalog
+        connection.drop_join_table :artists, :musics, table_name: :catalog
+
+        assert !connection.table_exists?("catalog")
+      end
+
+      def test_drop_join_table_with_the_table_name_as_string
+        connection.create_join_table :artists, :musics, table_name: "catalog"
+        connection.drop_join_table :artists, :musics, table_name: "catalog"
+
+        assert !connection.table_exists?("catalog")
+      end
+
+      def test_drop_join_table_with_column_options
+        connection.create_join_table :artists, :musics, column_options: { null: true }
+        connection.drop_join_table :artists, :musics, column_options: { null: true }
+
+        assert !connection.table_exists?("artists_musics")
+      end
+
+      def test_create_and_drop_join_table_with_common_prefix
+        with_table_cleanup do
+          connection.create_join_table "audio_artists", "audio_musics"
+          assert connection.table_exists?("audio_artists_musics")
+
+          connection.drop_join_table "audio_artists", "audio_musics"
+          assert !connection.table_exists?("audio_artists_musics"), "Should have dropped join table, but didn't"
+        end
+      end
+
+      if current_adapter?(:PostgreSQLAdapter)
+        def test_create_join_table_with_uuid
+          connection.create_join_table :artists, :musics, column_options: { type: :uuid }
+          assert_equal [:uuid, :uuid], connection.columns(:artists_musics).map(&:type)
+        end
+      end
+
+      private
+
+        def with_table_cleanup
+          tables_before = connection.data_sources
+
+          yield
+        ensure
+          tables_after = connection.data_sources - tables_before
+
+          tables_after.each do |table|
+            connection.drop_table table
+          end
+        end
+    end
+  end
+end