Type Alias CustomOutputAsserter<FunctionToCall>

CustomOutputAsserter<FunctionToCall>: ((actual: Awaited<ReturnType<FunctionToCall>>, expected: Awaited<ReturnType<FunctionToCall>>, failureMessage?: string) => void)

A customer asserter for .output guards (assert.output, check.output, etc.). This is typically not necessary, as the .output guards already perform deep equality checks by default.

Type Parameters

  • FunctionToCall extends AnyFunction

    The function type that your custom asserter will be run on.

import {assert, AssertionError, CustomOutputAsserter} from '@augment-vir/assert';

function myFunctionToTest(name: string) {
return `Hello there ${name}`;
}

const myCustomAsserter: CustomOutputAsserter<typeof myFunctionToTest> = (
actual,
expected,
failureMessage,
) => {
// Write your assertion in an `if`.
if (!actual.startsWith('hello there') || actual.endsWith(expected)) {
// Throw an `AssertionError` if the `if` fails.
throw new AssertionError('', failureMessage);
}
};
// Use your custom asserter as the first input to any `.output` guard.
assert.output(myCustomAsserter, myFunctionToTest, ['John'], 'John', 'Name insertion failed');