Assert.every()

added in 0.0.1 • updated in 0.5.0 • last revisions

Syntax

function every<T>(array: readonly T[], callback: (value: T, index: number) => void | boolean, name?: string): void

Asserts that every element of an array passes an arbitrary assertion.

Parameters
`array`	The array whose elements to check.
`callback`	A callback that will be called once for every array element and should throw an assertion error (via one of the other assertion functions) if the element does not pass the assertion. Alternatively it is possible to return a `boolean` from the callback, but this will generate an unexpressive default error message if the assertion fails and is therefore not encouraged.
`name` Optional	A variable, property, or parameter name which, if specified, will print the name as part of the assertion error to make it more clear where the error originated.

Example

import { Assert } from 'potence';

const bits = [1, 1, 1, 1, 0, 1];

Assert.every(bits, bit => Assert.truthy(bit), 'bits');
// AssertionError: "bits failed assertion. Element at index 4 reported:
// "Assertion failed: expected truthy value but got 0"

Remarks

If the assertion fails, the error message prints out the index of the first element which failed, along with the failure message of the “inner” assertion error.

Note that iteration over the array stops as soon as one of the callbacks throws an assertion error.