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typescript/no-unnecessary-parameter-property-assignment Correctness

✅ This rule is turned on by default.

💡 A suggestion is available for this rule.

What it does

Prevents unnecessary assignment of parameter properties.

Why is this bad?

Constructor parameters marked with one of the visibility modifiers public, private, protected, or readonly are automatically initialized. Providing an explicit assignment is unnecessary and can be removed.

Examples

Examples of incorrect code for this rule:

class Foo {
  constructor(public name: unknown) {
    this.name = name;
  }
}

Examples of correct code for this rule:

class Foo {
  constructor(public name: unknown) {}
}

How to use

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

Config (.oxlintrc.json)

{
  "rules": {
    "typescript/no-unnecessary-parameter-property-assignment": "error"
  }
}

Config (oxlint.config.ts)

import { defineConfig } from "oxlint";

export default defineConfig({
  rules: {
    "typescript/no-unnecessary-parameter-property-assignment": "error",
  },
});

CLI

oxlint --deny typescript/no-unnecessary-parameter-property-assignment

Version

This rule was added in v0.15.13.

References

• Rule Source
• Upstream rule docs
• Open rule in Oxc Playground