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Using "arguments" keyword with Function.prototype.apply causes TS2345 #36470
Description
TypeScript Version: 3.7.5
Search Terms:
typescript function prototype apply arguments
Code
window.console.log = (() => {
const originalFn = window.console.log;
return function () {
console.error('Called wrapped console.log()');
return originalFn.apply(window.console, arguments);
}
})();
console.log(1, 2, 3);Expected behavior:
That snippet is valid JS code, it shouldn't cause an error.
Actual behavior:
It causes a TS2345 error because IArguments is not compatible with T[].
Related Issues:
-
Activity
RyanCavanaugh commentedon Jan 29, 2020
When
applysynthesizes its argument type, it produces a tuple type like[any?, ...args: any[]]. Tuple types imply that they are actually implemented asArrays (e.g. you can use non-mutating methods likeslice), but this isn't strictly necessary forcall/apply- they can work onArrayLikes, which make sense becauseargumentsis only array-like (it's not really an array). So the more accurate type would be something likeArrayLikeify<[any?, ...args: any[]]>whereArrayLikeifywould somehow just move over the non-array bits, but we're not super equipped to do this right now.dead-claudia commentedon Apr 6, 2020
I have a local workaround for this:
Obviously unsafe and I'm not sure if it's ideal for everyone, but it works well enough for me.
zengyuanqiu commentedon May 4, 2023
MDN
The apply() method calls the specified function with a given this value, and arguments provided as an array (or an array-like object)
zengyuanqiu commentedon May 4, 2023
MDN
The apply() method calls the specified function with a given this value, and arguments provided as an array (or an array-like object)