response.ts

// Copyright 2023-latest the httpland authors. All rights reserved. MIT license.
// This module is browser compatible.

import { equalsHeaders } from "./header.ts";
import { equalsType } from "./_utils.ts";

/** Check two `Response` fields equality.
 *
 * @example
 * ```ts
 * import { equalsResponse } from "https://deno.land/x/http_utils@$VERSION/response.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(
 *   equalsResponse(
 *     new Response(null, { status: 204, headers: { "content-length": "0" } }),
 *     new Response(null, { status: 204, headers: { "content-length": "0" } }),
 *   ),
 * );
 * ```
 *
 * @deprecated Move to [response-utils](https://github.com/httpland/response-utils).
 */
export function equalsResponse(left: Response, right: Response): boolean;
/** Strict check two `Response` fields equality.
 *
 * @example
 * ```ts
 * import { equalsResponse } from "https://deno.land/x/http_utils@$VERSION/response.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(
 *   await equalsResponse(
 *     new Response("test1", { status: 200, headers: { "content-length": "5" } }),
 *     new Response("test2", { status: 200, headers: { "content-length": "5" } }),
 *     false,
 *   ),
 * );
 * ```
 *
 * @throws {Error} In strict mode, if response body has already been read.
 */
export function equalsResponse(
  left: Response,
  right: Response,
  strict: boolean,
): boolean | Promise<boolean>;
export function equalsResponse(
  left: Response,
  right: Response,
  strict?: boolean,
): boolean | Promise<boolean> {
  strict ??= false;

  const staticResult = left.ok === right.ok &&
    left.bodyUsed === right.bodyUsed &&
    left.redirected === right.redirected &&
    left.status === right.status &&
    left.statusText === right.statusText &&
    left.type === right.type &&
    left.url === right.url &&
    equalsType(left.body, right.body) &&
    equalsHeaders(left.headers, right.headers);

  if (!staticResult || !strict) return staticResult;

  if (left.bodyUsed || right.bodyUsed) {
    throw Error(
      "response body has already been read and the body cannot be strictly compared",
    );
  }

  return Promise.all([left.clone().text(), right.clone().text()]).then((
    [left, right],
  ) => Object.is(left, right));
}

/** Whether the input is `Response` or not.
 *
 * ```ts
 * import { isResponse } from "https://deno.land/x/http_utils@$VERSION/response.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(isResponse(new Response()), true);
 * assertEquals(isResponse({}), false);
 * assertEquals(isResponse(null), false);
 * ```
 *
 * @deprecated Move to [response-utils](https://github.com/httpland/response-utils).
 */
export function isResponse(input: unknown): input is Response {
  return input instanceof Response;
}