How to Fix: How to test the type of a thrown exception in Jest

In Jest, you can use the t.error method to test the type of an exception thrown by a function.

💡 How to Use it

• Pass the expected error type as the first argument:

it('should throw TypeError when no params were passed', (t) => {
  t.error(() => {
    throwError();
  }, TypeError);
  t.is(true, true); // You can add additional assertions here
});

Alternatively, you can use the t.throws method with a regular expression to match the error type:

it('should throw TypeError when no params were passed', (t) => {
  t.throws(() => {
    throwError();
  }, /TypeError/);
  t.is(true, true); // You can add additional assertions here
});

✅ Best Solutions to Fix It

🎯 Final Words

By using t.error or a regular expression with t.throws, you can easily test the type of an exception thrown by a function in Jest.