Assume that type node annotations resolving to error types can be reused #60195
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| // allow "reusing" type nodes that resolve to error types | ||
| // those can't truly be reused but it prevents cascading errors in isolatedDeclarations | ||
| // for source with errors there is no guarantee to emit correct code anyway | ||
| return true; | ||
| } |
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This could be handled elsewhere but this place is an easy and effective fix.
Note that in a sense this was already happening - just in different situations. Consider this:
export const foo3 = (type: Unresolved): void => {};In here both the annotationType and type are error types, they just happen to be the same aliased error types. So they are assumed to be the same on the basis of typeFromTypeNode === type in typeNodeIsEquivalentToType.
The reported case is the same yet different. Both types are also error types there but the type is a regular non-aliased error type whereas the annotationType is an aliased error type. Based on that typeNodeIsEquivalentToType doesn't assume that they are the same and thus typeFromParameter goes into inferTypeOfDeclaration which leads to reporting the error.
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Is there a condition in which this will cause us to try and print something unprintable?
Or will it not matter because it'll be an error anyway?
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I propose this fix mainly on the assumption of "will it not matter because it'll be an error anyway". It seems to me that if the error is there anyway then any emit is basically a fair game. It should reuse the annotation node - so at the very least it should just be broken in the same way.
This change allows type node annotations that resolve to error types to be reused in isolated declarations mode. This prevents cascading errors when source code contains unresolved type references. The fix adds: 1. A check in tryReuseExistingNonParameterTypeNode to detect error types and allow reuse 2. Logic in serializeTypeForDeclaration to attempt reusing existing type annotations before generating new ones This matches the behavior from microsoft/TypeScript#60195 which fixes issue #60192. Co-authored-by: RyanCavanaugh <[email protected]>
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fixes #60192
similar to #60129