Fix issue with expression patterns in switch exhaustivity checking #23804
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@swift-ci Please test |
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@swift-ci Please test source compatibility |
CodaFi
reviewed
Apr 4, 2019
| @@ -1448,6 +1449,8 @@ namespace { | |||
| } | |||
| } else if (SP->getKind() == PatternKind::Tuple) { | |||
| Space argTupleSpace = projectPattern(TC, SP); | |||
| if (argTupleSpace.isEmpty()) | |||
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Same source compat failures seen elsewhere. @rintaro (current Apple build czar), do we have bugs tracking these? |
Expression patterns (and cast patterns) don't actually contribute to the exhaustivity of a switch statement---if you're matching against a String, matching "abc" doesn't meaningfully reduce the full space of the values you have to match. This was already handled, but didn't do the right thing in a particular case involving a tuple payload in an enum after the Space Engine (exhaustivity checker) optimizations that went out in Swift 5. https://bugs.swift.org/browse/SR-10301
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@swift-ci Please smoke test |
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Yes. rdar://problem/49610988 |
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Apr 5, 2019
…wiftlang#23804) Expression patterns (and cast patterns) don't actually contribute to the exhaustivity of a switch statement---if you're matching against a String, matching "abc" doesn't meaningfully reduce the full space of the values you have to match. This was already handled, but didn't do the right thing in a particular case involving a tuple payload in an enum after the Space Engine (exhaustivity checker) optimizations that went out in Swift 5. https://bugs.swift.org/browse/SR-10301 (cherry picked from commit d36a739)
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Expression patterns (and cast patterns) don't actually contribute to the exhaustivity of a switch statement—if you're matching against a String, matching "abc" doesn't meaningfully reduce the full space of the values you have to match. This was already handled, but didn't do the right thing in a particular case involving a tuple payload in an enum after the Space Engine (exhaustivity checker) optimizations that went out in Swift 5.
SR-10301 / rdar://problem/49609445