| commit | a11aeeb5007bb118e49c60ff84c6edbfab4232a4 | [log] [tgz] |
|---|---|---|
| author | Stephen Adams <sra@google.com> | Thu Jan 30 20:45:49 2025 -0800 |
| committer | Stephen Adams <sra@google.com> | Thu Jan 30 20:45:49 2025 -0800 |
| tree | 7efa8f05ff4d7a063cba11a3ac5706103e0320b9 | |
| parent | e038d8ac8144cae1fbdd0185b3e901901b471993 [diff] |
[dart2js] Annotation for exception stacks with shorter prefix
Dart's `throw` expression does not correspond exactly to JavaScript's `throw` statement. To implement Dart semantics, and to reduce code size, dart2js uses the functions `wrapException` and `throwExpression` from the dart2js runtime. As a result, these functions appear in the stack trace (one or both).
A consequence of this is that a fixed prefix of an error stack is less useful, as potentially interesting frames are forced out of the prefix by these 'noise' frames.
This change ensures only one of the helpers on the stack trace.
It is also possible to get rid of the helper frame by an annotation.
The annotation `@pragma('dart2js:stack-starts-at-throw')` causes the stack to be captured in the current JavaScript function rather than in a helper. The cost is more code at the call site, about 12 bytes per `throw` expression in minified code. The annotation can be placed on a method, class or library, and applies to all `throw` expression in the scope of the annotated element.
This change uses the annotation to remove noise frames from type errors and some other errors in the runtime.
Change-Id: If15184a5963fb054199177bb4526b32f25e53fe9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/406684
Reviewed-by: Mayank Patke <fishythefish@google.com>
Reviewed-by: Nate Biggs <natebiggs@google.com>
Dart is:
Approachable: Develop with a strongly typed programming language that is consistent, concise, and offers modern language features like null safety and patterns.
Portable: Compile to ARM, x64, or RISC-V machine code for mobile, desktop, and backend. Compile to JavaScript or WebAssembly for the web.
Productive: Make changes iteratively: use hot reload to see the result instantly in your running app. Diagnose app issues using DevTools.
Dart's flexible compiler technology lets you run Dart code in different ways, depending on your target platform and goals:
Dart Native: For programs targeting devices (mobile, desktop, server, and more), Dart Native includes both a Dart VM with JIT (just-in-time) compilation and an AOT (ahead-of-time) compiler for producing machine code.
Dart Web: For programs targeting the web, Dart Web includes both a development time compiler (dartdevc) and a production time compiler (dart2js).
Dart is free and open source.
See LICENSE and PATENT_GRANT.
Visit dart.dev to learn more about the language, tools, and to find codelabs.
Browse pub.dev for more packages and libraries contributed by the community and the Dart team.
Our API reference documentation is published at api.dart.dev, based on the stable release. (We also publish docs from our beta and dev channels, as well as from the primary development branch).
If you want to build Dart yourself, here is a guide to getting the source, preparing your machine to build the SDK, and building.
There are more documents in our repo at docs.
The easiest way to contribute to Dart is to file issues.
You can also contribute patches, as described in Contributing.
Future plans for Dart are included in the combined Dart and Flutter roadmap on the Flutter wiki.