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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.import { format } from "./_format.ts";import { AssertionError } from "./assertion_error.ts";import { buildMessage, diff, diffstr } from "./_diff.ts";import { CAN_NOT_DISPLAY } from "./_constants.ts";import { red } from "../fmt/colors.ts";
/** * Make an assertion that `actual` and `expected` are strictly equal. If * not then throw. * * @example * ```ts * import { assertStrictEquals } from "https://deno.land/std@$STD_VERSION/assert/assert_strict_equals.ts"; * * const a = {}; * const b = a; * assertStrictEquals(a, b); // Doesn't throw * * const c = {}; * const d = {}; * assertStrictEquals(c, d); // Throws * ``` */export function assertStrictEquals<T>( actual: unknown, expected: T, msg?: string,): asserts actual is T { if (Object.is(actual, expected)) { return; }
const msgSuffix = msg ? `: ${msg}` : "."; let message: string;
const actualString = format(actual); const expectedString = format(expected);
if (actualString === expectedString) { const withOffset = actualString .split("\n") .map((l) => ` ${l}`) .join("\n"); message = `Values have the same structure but are not reference-equal${msgSuffix}\n\n${ red(withOffset) }\n`; } else { try { const stringDiff = (typeof actual === "string") && (typeof expected === "string"); const diffResult = stringDiff ? diffstr(actual as string, expected as string) : diff(actualString.split("\n"), expectedString.split("\n")); const diffMsg = buildMessage(diffResult, { stringDiff }).join("\n"); message = `Values are not strictly equal${msgSuffix}\n${diffMsg}`; } catch { message = `\n${red(CAN_NOT_DISPLAY)} + \n\n`; } }
throw new AssertionError(message);}