Use any Error for caught error type of an exhaustive, non-throwing do..catch
#71129
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…do..catch
Prior to the introduction of typed throws, a `do..catch` always had a caught
error type of `any Error`, even if there were no throwing sites within
the `do` body. With typed throws, such a `do..catch` would have a
caught error type of `Never`, because it never throws. Unfortunately,
this causes code like the following to produce an error, because
`Never` cannot be pattern-matched to `HomeworkError.forgot`:
func test() {
do {
try nonthrowing()
} catch HomeworkError.forgot {
} catch {
}
}
For source-compatibility reasons, adjust the caught error type to
`any Error` in this case, so we continue to accept the code above.
Don't do this adjustment under `FullTypedThrows`, because it's only
there for compatibility.
Fixes rdar://121526201.
DougGregor
requested review from
hborla,
xedin,
ahoppen,
bnbarham,
CodaFi,
hamishknight,
rintaro and
slavapestov
as code owners
|
@swift-ci please smoke test |
|
No idea what this is from the Linux failure: |
|
@swift-ci please smoke test Linux |
1 similar comment
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@swift-ci please smoke test Linux |
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Prior to the introduction of typed throws, a
do..catchalways had a caught error type ofany Error, even if there were no throwing sites within thedobody. With typed throws, such ado..catchwould have a caught error type ofNever, because it never throws. Unfortunately, this causes code like the following to produce an error, becauseNevercannot be pattern-matched toHomeworkError.forgot:For source-compatibility reasons, adjust the caught error type to
any Errorin this case, so we continue to accept the code above. Don't do this adjustment underFullTypedThrows, because it's only there for compatibility.Fixes rdar://121526201.