1 files changed, 42 insertions, 0 deletions
diff --git a/activerecord/test/cases/migration/pending_migrations_test.rb b/activerecord/test/cases/migration/pending_migrations_test.rb
new file mode 100644
index 0000000000..119bfd372a
--- /dev/null
+++ b/activerecord/test/cases/migration/pending_migrations_test.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveRecord
+  class Migration
+    if current_adapter?(:SQLite3Adapter) && !in_memory_db?
+      class PendingMigrationsTest < ActiveRecord::TestCase
+        setup do
+          file = ActiveRecord::Base.connection.raw_connection.filename
+          @conn = ActiveRecord::Base.establish_connection adapter: "sqlite3", database: ":memory:", migrations_paths: MIGRATIONS_ROOT + "/valid"
+          source_db = SQLite3::Database.new file
+          dest_db = ActiveRecord::Base.connection.raw_connection
+          backup = SQLite3::Backup.new(dest_db, "main", source_db, "main")
+          backup.step(-1)
+          backup.finish
+        end
+
+        teardown do
+          @conn.release_connection if @conn
+          ActiveRecord::Base.establish_connection :arunit
+        end
+
+        def test_errors_if_pending
+          ActiveRecord::Base.connection.drop_table "schema_migrations", if_exists: true
+
+          assert_raises ActiveRecord::PendingMigrationError do
+            CheckPending.new(Proc.new { }).call({})
+          end
+        end
+
+        def test_checks_if_supported
+          ActiveRecord::SchemaMigration.create_table
+          migrator = Base.connection.migration_context
+          capture(:stdout) { migrator.migrate }
+
+          assert_nil CheckPending.new(Proc.new { }).call({})
+        end
+      end
+    end
+  end
+end