Revision: 6428
Author: [email protected]
Date: Fri Jan 21 03:44:29 2011
Log: Return the empty string when formatting recursive error messages. This
matches the behavior of Safari and Firefox. Our old behavior was to
throw a stack overflow exception.
BUG=crbug.com/70334
TEST=mjsunit/cyclic-error-to-string.js
Review URL: http://codereview.chromium.org/6261018
http://code.google.com/p/v8/source/detail?r=6428
Added:
/branches/bleeding_edge/test/mjsunit/cyclic-error-to-string.js
Modified:
/branches/bleeding_edge/src/messages.js
=======================================
--- /dev/null
+++ /branches/bleeding_edge/test/mjsunit/cyclic-error-to-string.js Fri Jan
21 03:44:29 2011
@@ -0,0 +1,46 @@
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following
+// disclaimer in the documentation and/or other materials provided
+// with the distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived
+// from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Test printing of cyclic errors which return the empty string for
+// compatibility with Safari and Firefox.
+
+var e = new Error();
+assertEquals('Error', e + '');
+
+e = new Error();
+e.name = e;
+e.message = e;
+e.stack = e;
+e.arguments = e;
+assertEquals('', e + '');
+
+e = new Error();
+e.name = [ e ];
+e.message = [ e ];
+e.stack = [ e ];
+e.arguments = [ e ];
+assertEquals('', e + '');
=======================================
--- /branches/bleeding_edge/src/messages.js Thu Jan 20 10:51:47 2011
+++ /branches/bleeding_edge/src/messages.js Fri Jan 21 03:44:29 2011
@@ -1011,20 +1011,48 @@
// Setup extra properties of the Error.prototype object.
$Error.prototype.message = '';
+
+// Global list of error objects visited during errorToString. This is
+// used to detect cycles in error toString formatting.
+var visited_errors = new $Array();
+var cyclic_error_marker = new $Object();
+
+function errorToStringDetectCycle() {
+ if (!%PushIfAbsent(visited_errors, this)) throw cyclic_error_marker;
+ try {
+ var type = this.type;
+ if (type && !this.hasOwnProperty("message")) {
+ var formatted = FormatMessage({ type: type, args: this.arguments });
+ return this.name + ": " + formatted;
+ }
+ var message = this.hasOwnProperty("message") ? (": " +
this.message) : "";
+ return this.name + message;
+ } finally {
+ visited_errors.pop();
+ }
+}
function errorToString() {
- var type = this.type;
- if (type && !this.hasOwnProperty("message")) {
- return this.name + ": " + FormatMessage({ type: type, args:
this.arguments });
- }
- var message = this.hasOwnProperty("message") ? (": " +
this.message) : "";
- return this.name + message;
+ // These helper functions are needed because access to properties on
+ // the builtins object do not work inside of a catch clause.
+ function isCyclicErrorMarker(o) { return o === cyclic_error_marker; }
+ function isVisitedErrorsEmpty() { return visited_errors.length === 0; }
+
+ try {
+ return %_CallFunction(this, errorToStringDetectCycle);
+ } catch(e) {
+ // Propagate cyclic_error_marker exception until all error
+ // formatting is finished and then return the empty string. Safari
+ // and Firefox also returns the empty string when converting a
+ // cyclic error to a string.
+ if (isCyclicErrorMarker(e) && isVisitedErrorsEmpty()) return '';
+ else throw e;
+ }
}
%FunctionSetName(errorToString, 'toString');
%SetProperty($Error.prototype, 'toString', errorToString, DONT_ENUM);
-
// Boilerplate for exceptions for stack overflows. Used from
// Top::StackOverflow().
const kStackOverflowBoilerplate = MakeRangeError('stack_overflow', []);
--
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