Ömer Ağacan
992a07a552
Reuse dart2js's source map extension format to map minified class names
shown in error messages and runtime type strings ("minified:Class123")
to original class names.
The extension field is only generated when minifying, and with multiple
modules, only in the main module's source map.
- Without minification runtime type strings and error messages already
include the full class name, so mapping is not necessary.
- With multiple modules, the existing tools use the main module's source
map to deobfuscate errors.
Because wasm-opt is not aware of this custom section and it also changes
the names section, when optimizing, we read the original names before
calling wasm-opt, and write the section back to the source map file for
the optimized Wasm.
When not optimizing we generate the source map with the custom section
directly.
Example deobfuscation using the new source maps:
$ dart pkg/dart2js_tools/bin/lookup_name.dart test.wasm.map Class123
Class123 => AsyncError (a global name)
The custom section is a bit verbose for what dart2wasm needs: we could
map numbers to name indices instead of strings to name indices, as
dart2wasm minifies class names to numbers. However to avoid updating a
bunch of tools in g3, SDK, maybe also in Flutter and devtools, we reuse
dart2js's format, at least for now.
Issue: https://github.com/dart-lang/sdk/issues/60711
Change-Id: I2cda331723c6f0c7e7ef5f4772feaf420dc8c6ba
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/474660
Commit-Queue: Ömer Ağacan <omersa@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Dart
An approachable, portable, and productive language for high-quality apps on any platform
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).
License & patents
Dart is free and open source.
See LICENSE and PATENT_GRANT.
Using Dart
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).
Building Dart
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.
Contributing to Dart
The easiest way to contribute to Dart is to file issues.
You can also contribute patches, as described in Contributing.
Roadmap
Future plans for Dart are included in the combined Dart and Flutter roadmap on the Flutter wiki.