Enforces getter/setter pairs in classes (accessor-pairs)

[feross]

https://eslint.org/docs/rules/accessor-pairs

Add the enforceForClassMembers option to the accessor-pairs rule.

Current rule:

    "accessor-pairs": "error",

Proposed rule:

"accessor-pairs": ["error", { "setWithoutGet": true, "enforceForClassMembers": true }],

enforceForClassMembers

By default, this rule does not enforce getter/setter pairs in class declarations and class expressions,
as the default value for enforceForClassMembers is false.

When enforceForClassMembers is set to true:

• "setWithoutGet": true will also warn for setters without getters in classes.

Examples of incorrect code for { "setWithoutGet": true, "enforceForClassMembers": true }:

/*eslint accessor-pairs: ["error", { "setWithoutGet": true, "enforceForClassMembers": true }]*/

class Foo {
    set a(value) {
        this.val = value;
    }
}

const Bar = class {
    static set a(value) {
        this.val = value;
    }
}

[mightyiam]

I can think of at least one legit use case of using setters without getters. For example, in a test, where you pass a test object into some API that mutates it by assigning to its properties. If what you cared about is the order and perhaps timing of the mutations, then you could use setters to receive the values and make the assertions on that. You would not read from those properties, so there's no need for getters on those same properties. Does that sound like a legit use case?

[feross]

I agree that there seem to be valid use cases that this rule would prevent, but in practice it seems that it hasn't been an issue even though it's been enabled since this rule has been present ("setWithoutGet": true is the default).

So, let's also enforce it in classes to be consistent.

[feross]

0% ecosystem impact. This will ship in standard 16.