getEffectiveTypeParameterDeclarations: Always return a defined result #24251
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ghost
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sandersn
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May 18, 2018
| @@ -28199,8 +28196,8 @@ namespace ts { | |||
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| function checkGrammarConstructorTypeParameters(node: ConstructorDeclaration) { | |||
| const typeParameters = getEffectiveTypeParameterDeclarations(node); | |||
| if (typeParameters) { | |||
| const { pos, end } = isNodeArray(typeParameters) ? typeParameters : first(typeParameters); | |||
| if (isNodeArray(typeParameters)) { | |||
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Based on my reading of the new code, isNodeArray is only false when typeParameters is empty. So how did first(typeParameters) ever work? Was it just dead code?
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Yep, dead code. Maybe we should be linting that we never call isFoo(x) if x is already Foo, or is a type not assignable to Foo. (E.g. we shouldn't be able to call isIfStatement on an Expression.)
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This simplifies most of the uses of this function and helps with
--strictNullChecks.