eslint/no-dupe-class-members Correctness

✅ This rule is turned on by default.

What it does

Disallow duplicate class members

Why is this bad?

If there are declarations of the same name in class members, the last declaration overwrites other declarations silently. It can cause unexpected behaviors.

Example

class A {
  foo() {
    console.log("foo");
  }
  foo = 123;
}
let a = new A();
a.foo(); // Uncaught TypeError: a.foo is not a function

References

• Rule Source