Analyzer: Fix incorrect type in PropertyElementResolver._resolve.

The `unpromotedType` computed by `PropertyElementResolver._resolve`
(which eventually propagates to both `FlowAnalysis.propertyGet` and to
`PropertyElementResolverResult.getType`) is intended to represent the
static type of the "property get" expression in the absence of
promotion. If the property get targets a `PropertyAccessorElement` (a
getter), this is the getter's return type. But if it targets a
`MethodElement`, this is the function type of the method (because the
"property get" is doing a tear-off of the method).

Previously, `PropertyElementResolver._resolve` was always using the
return type, meaning that if the property get was targeting a
`MethodElement`, it was computing the wrong type. Fortunately, this
didn't lead to any bugs, because (a) the type passed to
`FlowAnalysis.propertyGet` is only used for determining whether a
field access should be promoted, and method tear-offs aren't
promotable, and (b) the analyzer only uses the type stored in
`PropertyElementResolverResult.getType` when the element being
targeted is a `PropertyAccessorElement`.

I'm in the middle of a larger arc of work trying to introduce a new,
simpler mechanism for flow analysis to be told about the static types
of property gets, and part of that arc of work will involve
introducing a temporary check to verify that the old and new
mechanisms see the same static types. Fixing this incorrect type will
allow the temporary check to pass.

Change-Id: Ib13b12d1176a781dc56c3e79c150df481b48a0d5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/390585
Commit-Queue: Paul Berry <paulberry@google.com>
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
1 file changed
tree: cdd41365eab0cd5edf678ee890670611122920ae
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. AUTHORS
  22. BUILD.gn
  23. CHANGELOG.md
  24. codereview.settings
  25. CONTRIBUTING.md
  26. DEPS
  27. LICENSE
  28. OWNERS
  29. PATENT_GRANT
  30. PRESUBMIT.py
  31. README.dart-sdk
  32. README.md
  33. sdk.code-workspace
  34. sdk_args.gni
  35. sdk_packages.yaml
  36. SECURITY.md
  37. WATCHLISTS
README.md

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).

Dart platforms illustration

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.