std/assert/assert_less_or_equal.ts
2024-04-29 11:57:30 +09:00

32 lines
849 B
TypeScript

// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
// This module is browser compatible.
import { format } from "@std/internal/format";
import { AssertionError } from "./assertion_error.ts";
/**
* Make an assertion that `actual` is less than or equal to `expected`.
* If not then throw.
*
* @example
* ```ts
* import { assertLessOrEqual } from "@std/assert/assert-less-or-equal";
*
* assertLessOrEqual(1, 2); // Doesn't throw
* assertLessOrEqual(1, 1); // Doesn't throw
* assertLessOrEqual(1, 0); // Throws
* ```
*/
export function assertLessOrEqual<T>(
actual: T,
expected: T,
msg?: string,
) {
if (actual <= expected) return;
const actualString = format(actual);
const expectedString = format(expected);
throw new AssertionError(
msg ?? `Expect ${actualString} <= ${expectedString}`,
);
}