== Why is this an issue?

If the function call can be written in a normal way, then calling that function with `.call()` or `.apply()` methods is redundant and can be removed without affecting the behavior of the code.

The `.call()` and `.apply()` methods are traditionally used to explicitely set the value of `this` keyword when executing a function or an object method. When calling a method of an object the value of `this` by default will be the reference to that object. But if you call a function or a method using `.call()` and `.apply()` you can set the value of `this` to any object, whatever you put into the first argument.

[source,javascript]
----
let obj = {
    checkThis() {
        this === obj; // true, if called the normal way: obj.checkThis()
    }
};

let otherObject = {};

obj.checkThis.call(otherObject); // this === otherObject, if called this way
----

There is also a special case when your code is not in https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Strict_mode[strict mode] and the first argument to the `.call()` and `.apply()` methods is `null` or `undefined`. In this case the value of `this` is substituted with the `globalThis` object, usually `window` when in browser context, and it make such call equivalent to just calling the function the normal way.

So if you are calling a function using `.call()` or `.apply()` methods and the first argument is `null` or `undefined`, or you are calling an object method and the first argument is the object itself, then `.call()` or `.apply()` methods become redundant, and should be removed to make the code more simple and easier to understand.


[source,javascript,diff-id=1,diff-type=noncompliant]
----
foo.call(null, 1, 2); // Noncompliant: .call() is redundant
obj.foo.call(obj, arg1, arg2); // Noncompliant: .call() is redundant
bar.apply(undefined, [x, y, z]); // Noncompliant: .apply() is redundant
----

To fix your code remove redundant `.call()` or `.apply()` methods.

[source,javascript,diff-id=1,diff-type=compliant]
----
foo(1, 2);
obj.foo(arg1, arg2);
bar(x, y, z);
----

== Resources
=== Documentation

* MDN web docs - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions[Functions]
* MDN web docs - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/call[Function.prototype.call()]
* MDN web docs - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/apply[Function.prototype.apply()]
* MDN web docs - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this[this]
* MDN web docs - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis[globalThis]