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// Copyright 2018-2023 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, assertThrows } from "https://deno.land/std@$STD_VERSION/assert/mod.ts"; * * assertAlmostEquals(0.1, 0.2); * * // Using a custom tolerance value * assertAlmostEquals(0.1 + 0.2, 0.3, 1e-16); * assertThrows(() => assertAlmostEquals(0.1 + 0.2, 0.3, 1e-17)); * ``` */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}`,  );}