Indicates the failure of an assertion. All errors thrown by the node:assert module will be instances of the AssertionError class.

This feature is deprecated and will be removed in a future version. Please consider using alternatives such as the mock helper function.

An alias of ok.

Strict assertion mode

Tests for deep equality between the actual and expected parameters. "Deep" equality means that the enumerable "own" properties of child objects are recursively evaluated also by the following rules.

Expects the string input not to match the regular expression.

Awaits the asyncFn promise or, if asyncFn is a function, immediately calls the function and awaits the returned promise to complete. It will then check that the promise is not rejected.

Asserts that the function fn does not throw an error.

Strict assertion mode

Throws an AssertionError with the provided error message or a default error message. If the message parameter is an instance of an Error then it will be thrown instead of the AssertionError.

Throws value if value is not undefined or null. This is useful when testing the error argument in callbacks. The stack trace contains all frames from the error passed to ifError() including the potential new frames for ifError() itself.

Expects the string input to match the regular expression.

Strict assertion mode

Tests for deep strict inequality. Opposite of deepStrictEqual.

Strict assertion mode

Tests strict inequality between the actual and expected parameters as determined by Object.is().

Tests if value is truthy. It is equivalent to assert.equal(!!value, true, message).

assert.partialDeepStrictEqual() Asserts the equivalence between the actual and expected parameters through a deep comparison, ensuring that all properties in the expected parameter are present in the actual parameter with equivalent values, not allowing type coercion. The main difference with assert.deepStrictEqual() is that assert.partialDeepStrictEqual() does not require all properties in the actual parameter to be present in the expected parameter. This method should always pass the same test cases as assert.deepStrictEqual(), behaving as a super set of it.

Awaits the asyncFn promise or, if asyncFn is a function, immediately calls the function and awaits the returned promise to complete. It will then check that the promise is rejected.

Tests strict equality between the actual and expected parameters as determined by Object.is().

Expects the function fn to throw an error.

In strict assertion mode, non-strict methods behave like their corresponding strict methods. For example, deepEqual will behave like deepStrictEqual.