Kevin Millikin
9bdf2489b5
Implement the feature spec for checking returns against inferred function return types: https://github.com/dart-lang/sdk/blob/master/docs/language/informal/invalid_returns.md with the change that an invalid return without a subexpression is a warning, not an error. This is because it is a warning in the analyzer and it would be a breaking change to turn it into an error. The check for valid returns is moved to exactly where we handle returns, rather than in ensureAssignable which is used as a helper in a lot of places. A bug in type inference was fixed: we would use `void` for the type of return without a subexpression instead of `null`. To accommodate that we would use a non-standard subtyping relation for returns. This could lead to us inferring a return type of `void` in cases where we should not. Change-Id: Iee9ece9c722f47efa305f49490d3022d0bbb9f44 Reviewed-on: https://dart-review.googlesource.com/72403 Commit-Queue: Kevin Millikin <kmillikin@google.com> Reviewed-by: Aske Simon Christensen <askesc@google.com>
15 lines
414 B
Dart
15 lines
414 B
Dart
// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
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// for details. All rights reserved. Use of this source code is governed by a
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// BSD-style license that can be found in the LICENSE file.
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/*@testedFeatures=inference*/
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library test;
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f() {
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List<int> o;
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o. /*@target=Iterable::forEach*/ forEach(
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/*@returnType=int*/ (/*@type=int*/ i) => i /*@target=num::+*/ + 1);
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}
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main() {}
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