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Rslint

    no-useless-call

    Configuration

    rslint.config.ts
    import { defineConfig, js } from '@rslint/core';

export default defineConfig([
  js.configs.recommended,
  {
    rules: {
      'no-useless-call': 'error',
    },
  },
]);

    Rule Details

    Function.prototype.call() and Function.prototype.apply() are slower than the normal function invocation. This rule reports cases where .call() / .apply() does not change this (so the call could be a normal invocation).

    A call is reported when its thisArg matches the receiver implied by the applied expression:

    • foo.call(undefined, …) / foo.apply(null, …) — the applied expression has no implied this, so null/undefined/void 0 are equivalent to a plain call.
    • obj.foo.call(obj, …) / obj.foo.apply(obj, …) — the thisArg is the same expression (token-for-token) as the receiver of the applied member access.

    .apply() is only flagged when the second argument is an array literal — the variadic / spread case is the responsibility of prefer-spread.

    Examples of incorrect code for this rule:

    foo.call(undefined, 1, 2, 3);
foo.apply(undefined, [1, 2, 3]);
foo.call(null, 1, 2, 3);
foo.apply(null, [1, 2, 3]);

obj.foo.call(obj, 1, 2, 3);
obj.foo.apply(obj, [1, 2, 3]);

    Examples of correct code for this rule:

    // The `this` binding actually changes.
foo.call(obj, 1, 2, 3);
foo.apply(obj, [1, 2, 3]);
obj.foo.call(null, 1, 2, 3);
obj.foo.apply(null, [1, 2, 3]);
obj.foo.call(otherObj, 1, 2, 3);
obj.foo.apply(otherObj, [1, 2, 3]);

// Variadic is delegated to `prefer-spread`.
foo.apply(undefined, args);
foo.apply(null, args);
obj.foo.apply(obj, args);

    Original Documentation