1234567891011121314151617181920212223242526272829303132333435363738394041
// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.import { AssertionError } from "./assertion_error.ts";
/** * Make an assertion that `actual` and `expected` are almost equal numbers * through a given tolerance. It can be used to take into account IEEE-754 * double-precision floating-point representation limitations. If the values * are not almost equal then throw. * * @example * ```ts * import { assertAlmostEquals } from "https://deno.land/std@$STD_VERSION/assert/mod.ts"; * * assertAlmostEquals(0.01, 0.02, 0.1); // Doesn't throw * assertAlmostEquals(0.01, 0.02); // Throws * assertAlmostEquals(0.1 + 0.2, 0.3, 1e-16); // Doesn't throw * assertAlmostEquals(0.1 + 0.2, 0.3, 1e-17); // Throws * ``` */export function assertAlmostEquals(  actual: number,  expected: number,  tolerance = 1e-7,  msg?: string,) {  if (Object.is(actual, expected)) {    return;  }  const delta = Math.abs(expected - actual);  if (delta <= tolerance) {    return;  }
  const msgSuffix = msg ? `: ${msg}` : ".";  const f = (n: number) => Number.isInteger(n) ? n : n.toExponential();  throw new AssertionError(    `Expected actual: "${f(actual)}" to be close to "${f(expected)}": \delta "${f(delta)}" is greater than "${f(tolerance)}"${msgSuffix}`,  );}