fail()

Signature

fail() — returns void

Available in: test

Description

Forces a test to fail intentionally. You can call fail() inside a test when you want to stop execution and explicitly mark the test as failed or highlight cases that should never happen. When called, it throws an exception that results in a test failure. You can optionally pass a custom message to clarify why the failure occurred. Used in wheels legacy testing.

Parameters

Name	Type	Required	Default	Description
message	string	no	—

Examples

1. Simple fail with no message
function test_should_fail_on_purpose() {
 fail();
};

Marks the test as failed without explanation.

2. Fail with a custom message
function test_should_fail_with_a_message() {
 fail("This path should never be reached!");
};

Produces a failure with the message This path should never be reached!.

3. Guarding unexpected conditions
function test_should_not_allow_null_users() {
 var user = getUserById(123);
 if (isNull(user)) {
     fail("Expected user with ID 123 to exist but got null.");
 }
};