Bind assignments to 'this' within static blocks in JS files #46472
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| //// [a.d.ts] | ||
| declare class Thing { | ||
| } |
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This is wrong, but not something I would consider in scope for this PR. I will create a follow-up issue for doSomething getting dropped in the .d.ts output.
| constructor(arrayLength?: number); | ||
| constructor(arrayLength: number); | ||
| constructor(...items: any[]); |
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Honestly, I don't know why this needs to be duplicated in the .d.ts emit.
| ~~~~~~~~~~~~~ | ||
| !!! error TS2417: Class static side 'typeof ElementsArray' incorrectly extends base class static side '{ isArray(arg: any): arg is any[]; readonly prototype: any[]; }'. | ||
| !!! error TS2417: Types of property 'isArray' are incompatible. | ||
| !!! error TS2417: Type '(arg: any) => boolean' is not assignable to type '(arg: any) => arg is any[]'. |
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not related to this PR, but I'm curious as to why this.isArray ends up with type (arg: any) => boolean instead of (arg: any) => arg is any[]
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We don't try to infer type predicate signatures - users always have to write them out deliberately, and can't rely on contextual types.
But even if we did rely on contextual types, we have another issue with class members not using them #23911 😢
…t#46472) * Add failing test case. * Handle 'this' assignments on class static blocks in JavaScript. * Accepted baselines.
Fixes #46468