unicorn/prefer-class-fields Style

What it does

Prefers class field declarations over this assignments in constructors for static values.

Why is this bad?

Class field declarations are more readable and less error-prone than assigning static values to this in the constructor. Using class fields keeps the constructor cleaner and makes the intent clearer.

Examples

Examples of incorrect code for this rule:

class Foo {
  constructor() {
    this.bar = 1;
  }
}

Examples of correct code for this rule:

class Foo {
  bar = 1;
}

How to use

To enable this rule using the config file or in the CLI, you can use:

Config (.oxlintrc.json)

{
  "rules": {
    "unicorn/prefer-class-fields": "error"
  }
}

CLI

oxlint --deny unicorn/prefer-class-fields

References

• Rule Source