Dmitry Stefantsov
ce6f19da80
Bug: http://dartbug.com/40425 Change-Id: I640891b24ddaaceafe84460ea7396095ab42a0db Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/135647 Reviewed-by: Johnni Winther <johnniwinther@google.com> Commit-Queue: Dmitry Stefantsov <dmitryas@google.com>
51 lines
1.6 KiB
Dart
51 lines
1.6 KiB
Dart
// Copyright (c) 2020, 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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// The test checks that the new rules for falling over the last statement in a
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// case block is detected using flow analysis rather than a pre-determined list
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// of statements that should terminate the block. The new rules can be found at
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// the following link:
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// https://github.com/dart-lang/language/blob/master/accepted/future-releases/nnbd/feature-specification.md#errors-and-warnings
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bar() {}
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foo(int x, bool b) {
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switch (x) {
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// The only statement in the following case block doesn't complete normally
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// for any of its possible execution paths, so it's not a compile-time
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// error, even though the statement is not one of the list of statement that
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// should end any case block in pre-NNBD state.
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case 42:
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b ? throw "hest" : throw "fisk";
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// The following is still an error -- the statement completes normally.
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case -42: // Error.
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bar();
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// The following is not an error -- it's the last block in the switch
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// statement.
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default:
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bar();
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}
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}
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abstract class A {
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foo(int x, bool b) {
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switch (x) {
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// The following is not an error -- the expression in the only expression
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// statement of the following case block is of type Never, so it doesn't
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// complete normally.
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case 42:
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neverReturn();
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default:
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bar();
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}
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}
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Never neverReturn();
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}
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main() {}
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