Catch useless comparisons like `===` when it should set a value with `=`

Question

I am entering quite a large project where there have been several times that developers wanted set a value like:

x = 10;

but instead used

x === 10;

I want an eslint rule that could catch this but so far have had no luck in my search.

Would anyone know a rule using preferably eslint or a plugin for eslint?

Answer 1

You can catch this with no-unused-expressions ESLint rule.

let x;
x = 0; // -> no error
x === 10; // -> ESLint: Expected an assignment or function call and instead saw an expression.(no-unused-expressions)