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CallableFunction inference does not match runtime behavior #30294
Description
Activity
Ron Buckton (@rbuckton) bug or no?
Ryan Cavanaugh (@RyanCavanaugh): This is likely due to overload resolution related to
--strictBindCallApply, as we see the same error in this case:declare class C { static x(y: number): number; static x(): number; } C.x.call(C, 1); // error, but should be ok C.x.call(C); // ok C.x.call(1); // ok (not an error because the `this` type of `x` is not constrained)
Note that if you switch the order of the overloads, you get the exact opposite results (
C.x.call(C, 1)works butC.x.call(C)andC.x.call(1)fail).Ryan Cavanaugh (@RyanCavanaugh): Not a bug per se, as we have documented this is the expected behavior, however it does result in a poor user experience.
TypeScript Version: 3.4.0-dev.20190309
Search Terms: CallableFunction, call, bind, inference
Code
Expected behavior:
Promise.resolve.call(1)should trigger a compile-time errorPromise.resolve.call(Promise, 1)should compileActual behavior:
The situation is reversed. The one that works in runtime does not compile. The one that does compile throws a runtime error.
Promise.resolve.call(1)compiles without error, throwsUncaught TypeError: PromiseResolve called on non-objectin runtimePromise.resolve.call(Promise, 1)gives a compile-time error (Expected 1 arguments, but got 2.), works fine in runtime (returns aPromise<number>)I'm using
"lib": ["dom", "esnext"], "target: "es2015". Tested on Chrome 72.0.3626.121, V8 7.2.502.28.Playground Link: The compile-time error is not there, but the runtime exception can be observed