1 files changed, 111 insertions, 0 deletions
diff --git a/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
new file mode 100644
index 0000000000..c895ab9db5
--- /dev/null
+++ b/activerecord/test/cases/adapters/postgresql/referential_integrity_test.rb
@@ -0,0 +1,111 @@
+require 'cases/helper'
+require 'support/connection_helper'
+
+class PostgreSQLReferentialIntegrityTest < ActiveRecord::PostgreSQLTestCase
+  self.use_transactional_tests = false
+
+  include ConnectionHelper
+
+  IS_REFERENTIAL_INTEGRITY_SQL = lambda do |sql|
+    sql.match(/DISABLE TRIGGER ALL/) || sql.match(/ENABLE TRIGGER ALL/)
+  end
+
+  module MissingSuperuserPrivileges
+    def execute(sql)
+      if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
+        super "BROKEN;" rescue nil # put transaction in broken state
+        raise ActiveRecord::StatementInvalid, 'PG::InsufficientPrivilege'
+      else
+        super
+      end
+    end
+  end
+
+  module ProgrammerMistake
+    def execute(sql)
+      if IS_REFERENTIAL_INTEGRITY_SQL.call(sql)
+        raise ArgumentError, 'something is not right.'
+      else
+        super
+      end
+    end
+  end
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+  end
+
+  def teardown
+    reset_connection
+    if ActiveRecord::Base.connection.is_a?(MissingSuperuserPrivileges)
+      raise "MissingSuperuserPrivileges patch was not removed"
+    end
+  end
+
+  def test_should_reraise_invalid_foreign_key_exception_and_show_warning
+    @connection.extend MissingSuperuserPrivileges
+
+    warning = capture(:stderr) do
+      e = assert_raises(ActiveRecord::InvalidForeignKey) do
+        @connection.disable_referential_integrity do
+          raise ActiveRecord::InvalidForeignKey, 'Should be re-raised'
+        end
+      end
+      assert_equal 'Should be re-raised', e.message
+    end
+    assert_match (/WARNING: Rails was not able to disable referential integrity/), warning
+    assert_match (/cause: PG::InsufficientPrivilege/), warning
+  end
+
+  def test_does_not_print_warning_if_no_invalid_foreign_key_exception_was_raised
+    @connection.extend MissingSuperuserPrivileges
+
+    warning = capture(:stderr) do
+      e = assert_raises(ActiveRecord::StatementInvalid) do
+        @connection.disable_referential_integrity do
+          raise ActiveRecord::StatementInvalid, 'Should be re-raised'
+        end
+      end
+      assert_equal 'Should be re-raised', e.message
+    end
+    assert warning.blank?, "expected no warnings but got:\n#{warning}"
+  end
+
+  def test_does_not_break_transactions
+    @connection.extend MissingSuperuserPrivileges
+
+    @connection.transaction do
+      @connection.disable_referential_integrity do
+        assert_transaction_is_not_broken
+      end
+      assert_transaction_is_not_broken
+    end
+  end
+
+  def test_does_not_break_nested_transactions
+    @connection.extend MissingSuperuserPrivileges
+
+    @connection.transaction do
+      @connection.transaction(requires_new: true) do
+        @connection.disable_referential_integrity do
+          assert_transaction_is_not_broken
+        end
+      end
+      assert_transaction_is_not_broken
+    end
+  end
+
+  def test_only_catch_active_record_errors_others_bubble_up
+    @connection.extend ProgrammerMistake
+
+    assert_raises ArgumentError do
+      @connection.disable_referential_integrity {}
+    end
+  end
+
+  private
+
+  def assert_transaction_is_not_broken
+    assert_equal 1, @connection.select_value("SELECT 1")
+  end
+end