1 files changed, 257 insertions, 0 deletions
diff --git a/activerecord/test/cases/migration/references_foreign_key_test.rb b/activerecord/test/cases/migration/references_foreign_key_test.rb
new file mode 100644
index 0000000000..7a092103c7
--- /dev/null
+++ b/activerecord/test/cases/migration/references_foreign_key_test.rb
@@ -0,0 +1,257 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+if ActiveRecord::Base.connection.supports_foreign_keys_in_create?
+  module ActiveRecord
+    class Migration
+      class ReferencesForeignKeyInCreateTest < ActiveRecord::TestCase
+        setup do
+          @connection = ActiveRecord::Base.connection
+          @connection.create_table(:testing_parents, force: true)
+        end
+
+        teardown do
+          @connection.drop_table "testings", if_exists: true
+          @connection.drop_table "testing_parents", if_exists: true
+        end
+
+        test "foreign keys can be created with the table" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, foreign_key: true
+          end
+
+          fk = @connection.foreign_keys("testings").first
+          assert_equal "testings", fk.from_table
+          assert_equal "testing_parents", fk.to_table
+        end
+
+        test "no foreign key is created by default" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent
+          end
+
+          assert_equal [], @connection.foreign_keys("testings")
+        end
+
+        test "foreign keys can be created in one query when index is not added" do
+          assert_queries(1) do
+            @connection.create_table :testings do |t|
+              t.references :testing_parent, foreign_key: true, index: false
+            end
+          end
+        end
+
+        test "options hash can be passed" do
+          @connection.change_table :testing_parents do |t|
+            t.references :other, index: { unique: true }
+          end
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, foreign_key: { primary_key: :other_id }
+          end
+
+          fk = @connection.foreign_keys("testings").find { |k| k.to_table == "testing_parents" }
+          assert_equal "other_id", fk.primary_key
+        end
+
+        test "to_table option can be passed" do
+          @connection.create_table :testings do |t|
+            t.references :parent, foreign_key: { to_table: :testing_parents }
+          end
+          fks = @connection.foreign_keys("testings")
+          assert_equal([["testings", "testing_parents", "parent_id"]],
+                       fks.map { |fk| [fk.from_table, fk.to_table, fk.column] })
+        end
+      end
+    end
+  end
+end
+
+if ActiveRecord::Base.connection.supports_foreign_keys?
+  module ActiveRecord
+    class Migration
+      class ReferencesForeignKeyTest < ActiveRecord::TestCase
+        setup do
+          @connection = ActiveRecord::Base.connection
+          @connection.create_table(:testing_parents, force: true)
+        end
+
+        teardown do
+          @connection.drop_table "testings", if_exists: true
+          @connection.drop_table "testing_parents", if_exists: true
+        end
+
+        test "foreign keys cannot be added to polymorphic relations when creating the table" do
+          @connection.create_table :testings do |t|
+            assert_raises(ArgumentError) do
+              t.references :testing_parent, polymorphic: true, foreign_key: true
+            end
+          end
+        end
+
+        test "foreign keys can be created while changing the table" do
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            t.references :testing_parent, foreign_key: true
+          end
+
+          fk = @connection.foreign_keys("testings").first
+          assert_equal "testings", fk.from_table
+          assert_equal "testing_parents", fk.to_table
+        end
+
+        test "foreign keys are not added by default when changing the table" do
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            t.references :testing_parent
+          end
+
+          assert_equal [], @connection.foreign_keys("testings")
+        end
+
+        test "foreign keys accept options when changing the table" do
+          @connection.change_table :testing_parents do |t|
+            t.references :other, index: { unique: true }
+          end
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            t.references :testing_parent, foreign_key: { primary_key: :other_id }
+          end
+
+          fk = @connection.foreign_keys("testings").find { |k| k.to_table == "testing_parents" }
+          assert_equal "other_id", fk.primary_key
+        end
+
+        test "foreign keys cannot be added to polymorphic relations when changing the table" do
+          @connection.create_table :testings
+          @connection.change_table :testings do |t|
+            assert_raises(ArgumentError) do
+              t.references :testing_parent, polymorphic: true, foreign_key: true
+            end
+          end
+        end
+
+        test "foreign key column can be removed" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, index: true, foreign_key: true
+          end
+
+          assert_difference "@connection.foreign_keys('testings').size", -1 do
+            @connection.remove_reference :testings, :testing_parent, foreign_key: true
+          end
+        end
+
+        test "removing column removes foreign key" do
+          @connection.create_table :testings do |t|
+            t.references :testing_parent, index: true, foreign_key: true
+          end
+
+          assert_difference "@connection.foreign_keys('testings').size", -1 do
+            @connection.remove_column :testings, :testing_parent_id
+          end
+        end
+
+        test "foreign key methods respect pluralize_table_names" do
+          begin
+            original_pluralize_table_names = ActiveRecord::Base.pluralize_table_names
+            ActiveRecord::Base.pluralize_table_names = false
+            @connection.create_table :testing
+            @connection.change_table :testing_parents do |t|
+              t.references :testing, foreign_key: true
+            end
+
+            fk = @connection.foreign_keys("testing_parents").first
+            assert_equal "testing_parents", fk.from_table
+            assert_equal "testing", fk.to_table
+
+            assert_difference "@connection.foreign_keys('testing_parents').size", -1 do
+              @connection.remove_reference :testing_parents, :testing, foreign_key: true
+            end
+          ensure
+            ActiveRecord::Base.pluralize_table_names = original_pluralize_table_names
+            @connection.drop_table "testing", if_exists: true
+          end
+        end
+
+        class CreateDogsMigration < ActiveRecord::Migration::Current
+          def change
+            create_table :dog_owners
+
+            create_table :dogs do |t|
+              t.references :dog_owner, foreign_key: true
+            end
+          end
+        end
+
+        def test_references_foreign_key_with_prefix
+          ActiveRecord::Base.table_name_prefix = "p_"
+          migration = CreateDogsMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          assert_equal 1, @connection.foreign_keys("p_dogs").size
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+          ActiveRecord::Base.table_name_prefix = nil
+        end
+
+        def test_references_foreign_key_with_suffix
+          ActiveRecord::Base.table_name_suffix = "_s"
+          migration = CreateDogsMigration.new
+          silence_stream($stdout) { migration.migrate(:up) }
+          assert_equal 1, @connection.foreign_keys("dogs_s").size
+        ensure
+          silence_stream($stdout) { migration.migrate(:down) }
+          ActiveRecord::Base.table_name_suffix = nil
+        end
+
+        test "multiple foreign keys can be added to the same table" do
+          @connection.create_table :testings do |t|
+            t.references :parent1, foreign_key: { to_table: :testing_parents }
+            t.references :parent2, foreign_key: { to_table: :testing_parents }
+          end
+
+          fks = @connection.foreign_keys("testings").sort_by(&:column)
+
+          fk_definitions = fks.map { |fk| [fk.from_table, fk.to_table, fk.column] }
+          assert_equal([["testings", "testing_parents", "parent1_id"],
+                        ["testings", "testing_parents", "parent2_id"]], fk_definitions)
+        end
+
+        test "multiple foreign keys can be removed to the selected one" do
+          @connection.create_table :testings do |t|
+            t.references :parent1, foreign_key: { to_table: :testing_parents }
+            t.references :parent2, foreign_key: { to_table: :testing_parents }
+          end
+
+          assert_difference "@connection.foreign_keys('testings').size", -1 do
+            @connection.remove_reference :testings, :parent1, foreign_key: { to_table: :testing_parents }
+          end
+
+          fks = @connection.foreign_keys("testings").sort_by(&:column)
+
+          fk_definitions = fks.map { |fk| [fk.from_table, fk.to_table, fk.column] }
+          assert_equal([["testings", "testing_parents", "parent2_id"]], fk_definitions)
+        end
+      end
+    end
+  end
+else
+  class ReferencesWithoutForeignKeySupportTest < ActiveRecord::TestCase
+    setup do
+      @connection = ActiveRecord::Base.connection
+      @connection.create_table(:testing_parents, force: true)
+    end
+
+    teardown do
+      @connection.drop_table("testings", if_exists: true)
+      @connection.drop_table("testing_parents", if_exists: true)
+    end
+
+    test "ignores foreign keys defined with the table" do
+      @connection.create_table :testings do |t|
+        t.references :testing_parent, foreign_key: true
+      end
+
+      assert_includes @connection.data_sources, "testings"
+    end
+  end
+end