[sql] Framework for allowing tests to handle errors.

sql/test/scoped_error_ignorer.h

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SQL_TEST_SCOPED_ERROR_IGNORER_H_
+#define SQL_TEST_SCOPED_ERROR_IGNORER_H_
+
+#include <set>
+
+#include "base/basictypes.h"
+#include "sql/connection.h"
+
+namespace sql {
+
+// sql::Connection and sql::Statement treat most SQLite errors as
+// fatal in debug mode.  The intention is to catch inappropriate uses
+// of SQL before the code is shipped to production.  This makes it
+// challenging to write tests for things like recovery from
+// corruption.  This scoper can be used to ignore selected errors
+// during a test.  Errors are ignored globally (on all connections).
+//
+// Since errors can be very context-dependent, the class is pedantic -
+// specific errors must be ignored, and every error ignored must be
+// seen.
+//
+// NOTE(shess): There are still fatal error cases this does not
+// address.  If your test is handling database errors and you're
+// hitting a case not handled, contact me.
+class ScopedErrorIgnorer {
+ public:
+  ScopedErrorIgnorer();
+  ~ScopedErrorIgnorer();
+
+  // Add an error to ignore.  Extended error codes can be ignored
+  // specifically, or the base code can ignore an entire group
+  // (SQLITE_IOERR_* versus SQLITE_IOERR).
+  void IgnoreError(int err);
+
+  // Allow containing test to check if the errors were encountered.
+  // Failure to call results in ADD_FAILURE() in destructor.
+  bool CheckIgnoredErrors();
+
+  // Record an error and check if it should be ignored.
+  bool ShouldIgnore(int err);
+
+ private:
+  // Storage for callback passed to Connection::SetErrorIgnorer().
+  Connection::ErrorIgnorerCallback callback_;
+
+  // Record whether CheckIgnoredErrors() has been called.
+  bool checked_;
+
+  // Errors to ignore.
+  std::set<int> ignore_errors_;
+
+  // Errors which have been ignored.
+  std::set<int> errors_ignored_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedErrorIgnorer);
+};
+
+}  // namespace sql
+
+#endif  // SQL_TEST_SCOPED_ERROR_IGNORER_H_