[Parser] When recovering from expression parsing don't stop at '{' #42214
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hamishknight
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When recovering from a parser error in an expression, we resumed parsing at a '{'. I assume this was because we wanted to continue inside e.g. an if-body if parsing the condition failed, but it's actually causing more issue because when parsing e.g.
```swift
expr + has - error +
functionTakesClosure {
}
```
we continue parsing at the `{` of the trailing closure, which is a completely garbage location to continue parsing.
The motivating example for this change was (in a result builder)
```swift
Text("\(island.#^COMPLETE^#)")
takeTrailingClosure {}
```
Here `Text(…)` has an error (because it contains a code completion token) and thus we skip `takeTrailingClosure`, effectively parsing
```swift
Text(….) {}
```
which the type checker wasn’t very happy with and thus refused to provide code completion. With this change, we completely drop `takeTrailingClosure {}`. The type checker is a lot happier with that.
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When recovering from a parser error in an expression, we resumed parsing at a '{'. I assume this was because we wanted to continue inside e.g. an if-body if parsing the condition failed, but it's actually causing more issue because when parsing e.g.
we continue parsing at the
{of the trailing closure, which is a completely garbage location to continue parsing.The motivating example for this change was (in a result builder)
Here
Text(…)has an error (because it contains a code completion token) and thus we skiptakeTrailingClosure, effectively parsingwhich the type checker wasn’t very happy with and thus refused to provide code completion. With this change, we completely drop
takeTrailingClosure {}. The type checker is a lot happier with that.rdar://78781625