Disallow unnecessary catch clauses (no-useless-catch)

The "extends": "eslint:recommended" property in a configuration file enables this rule.

A catch clause that only rethrows the original error is redundant, and has no effect on the runtime behavior of the program. These redundant clauses can be a source of confusion and code bloat, so it's better to disallow these unnecessary catch clauses.

Rule Details

This rule reports catch clauses that only throw the caught error.

Examples of incorrect code for this rule:

/*eslint no-useless-catch: "error"*/

try {
  doSomethingThatMightThrow();
} catch (e) {
  throw e;
}

try {
  doSomethingThatMightThrow();
} catch (e) {
  throw e;
} finally {
  cleanUp();
}

Examples of correct code for this rule:

/*eslint no-useless-catch: "error"*/

try {
  doSomethingThatMightThrow();
} catch (e) {
  doSomethingBeforeRethrow();
  throw e;
}

try {
  doSomethingThatMightThrow();
} catch (e) {
  handleError(e);
}

try {
  doSomethingThatMightThrow();
} finally {
  cleanUp();
}

When Not To Use It

If you don't want to be notified about unnecessary catch clauses, you can safely disable this rule.

Version

This rule was introduced in ESLint 5.11.0.

Resources

• Rule source
• Documentation source