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Rslint

    no-this-before-super

    Configuration

    PresetConfigured Value
    ✅ js.configs.recommended"error"
    rslint.config.ts
    import { defineConfig, js } from '@rslint/core';

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

    Rule Details

    Disallows use of this or super (for property access like super.foo) before calling super() in constructors of derived classes.

    In a derived class (a class that extends another class), the constructor must call super() before accessing this or super for property access. Accessing this or super before super() has been called will throw a ReferenceError at runtime.

    Examples of incorrect code for this rule:

    class A extends B {
  constructor() {
    this.a = 0; // "this" before "super()"
    super();
  }
}

class A extends B {
  constructor() {
    super.foo(); // "super" property access before "super()"
    super();
  }
}

class A extends B {
  constructor() {
    super(this.a); // "this" in super() arguments
  }
}

    Examples of correct code for this rule:

    class A extends B {
  constructor() {
    super();
    this.a = 0;
  }
}

class A {
  constructor() {
    this.a = 0; // OK - not a derived class
  }
}

class A extends B {
  constructor() {
    super();
    super.foo();
  }
}

    Original Documentation