Get [type] parameter types from @type tag #26694
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Previously only the return type was used in cases like this: ```js /** @type {<T>(param?: T) => T | undefined} */ function g(param) { return param; } ``` Now the type parameters from the type tag are used, and the compiler gets the type of the parameter by using the position in the signature of the type tag. Fixes #25618
ghost
approved these changes
Aug 27, 2018
src/compiler/utilities.ts
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| } | ||
| const typeTag = getJSDocType(node); | ||
| if (typeTag) { | ||
| if (isFunctionTypeNode(typeTag) && typeTag.typeParameters) { |
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Previously only the return type was used in cases like this:
Now the type parameters from the type tag are used, and the compiler gets the type of the parameter by using the position in the signature of the type tag.
Note that this isn't the most complete fix — it only works for function types written directly in the type tag, not type references. However, I don't think that's very common, so I'd prefer to wait until I have evidence that it is. (I believe that supporting arbitrary references would require quite a bit more code.)
Fixes #25618