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prefer-object-has-own

Prefer Object.hasOwn(...) over Object.prototype.hasOwnProperty.call(...).

Targeted pattern scope​

This rule targets property-ownership checks using hasOwnProperty.call.

What this rule reports​

This rule reports legacy Object.prototype.hasOwnProperty.call(...) patterns.

Why this rule exists​

Object.hasOwn(...) is shorter, clearer, and less error-prone.

❌ Incorrect​

Object.prototype.hasOwnProperty.call(record, "id");

✅ Correct​

Object.hasOwn(record, "id");

Behavior and migration notes​

This rule forwards options and behavior to ESLint core prefer-object-has-own.

Additional examples​

Object.prototype.hasOwnProperty.call(config, "port");
// ❌ reported

Object.hasOwn(config, "port");
// ✅ valid

ESLint flat config example​

import etcMisc from "eslint-plugin-etc-misc";

export default [
 {
  plugins: { "etc-misc": etcMisc },
  rules: {
   "etc-misc/prefer-object-has-own": "error",
  },
 },
];

When not to use it​

Disable this rule if you must support runtimes without Object.hasOwn(...) and cannot polyfill it.

Package documentation​

Rule catalog ID: R060

Further reading​

Adoption resources​

  • Start at warning level in CI, then move to error after cleanup.
  • Use focused codemods/autofix batches per package or directory.