Support Bun runtime

[OleksandrKucherenko]

Prerequisites

• I confirm my issue is not in the opened issues
• I confirm the Frequently Asked Questions didn't contain the answer to my issue

Environment check

• I'm using the latest msw version
• I'm using Node.js version 14 or higher

Node.js version

v18.15.0

Reproduction repository

OleksandrKucherenko/chatgpt-translate-md#8

Reproduction steps

• Take the branch - from PR Make possible execution via BUN tool OleksandrKucherenko/chatgpt-translate-md#8
• Install BUN curl -fsSL https://bun.sh/install | bash (details: https://bun.sh/)
• Run bun install
• Run bun test

Refs:

• Can be related to incomplete implementation of the TEST API in BUN: bun test oven-sh/bun#1825

Notes:
For switching between TS-NODE JEST and BUN you will need to changes lines:

this is YARN 3.xx monorepo with multiple packages, that I try to make compatible with BUN 0.8.1

Current behaviour

BUN produce this error

clis/gpt/src/gpt.test.ts:
879 |     if (this.aborted)
880 |       return;
881 |     this[kAbortController].abort();
882 |   }
883 | 
884 |   constructor(input, options, cb) {
                             ^
TypeError: Cannot call a class constructor without |new|
      at ClientRequest (node:http:884:26)
      at new NodeClientRequest (/Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/@mswjs/interceptors/lib/interceptors/ClientRequest/NodeClientRequest.js:104:20)
      at /Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/@mswjs/interceptors/lib/interceptors/ClientRequest/http.request.js:37:15
      at /Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/follow-redirects/index.js:284:8
      at new RedirectableRequest (/Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/follow-redirects/index.js:66:2)
      at request (/Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/follow-redirects/index.js:523:13)
      at /Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/axios/lib/adapters/http.js:438:10
      at dispatchHttpRequest (/Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/axios/lib/adapters/http.js:149:54)
      at /Users/o.kucherenko2/workspace/gitlabs/gpt.md.translate/node_modules/axios/lib/adapters/http.js:143:4
      at new Promise (:1:20)

Expected behavior

YARN+TS-NONE - produce this error

 FAIL  clis/gpt/src/gpt.test.ts
  ● gpt › should raise custom error on API error 429

    ⛔ API error.

      117 |   // raise errors on non-2xx responses or empty content
      118 |   if (!(response.status >= 200 && response.status < 300))
    > 119 |     throw new Error(Errors.ApiError, { cause: createAxiosError(response) })
          |           ^
      120 |   if (content === ``) throw new Error(Errors.EmptyContent)
      121 |
      122 |   return content

      at askGPT (clis/gpt/src/gpt.ts:119:11)
      at Object.<anonymous> (clis/gpt/src/gpt.test.ts:66:20)

    Cause:
    AxiosError: Request failed with status code 429

      3 | /** stolen from: axios/lib/core/settle.js:17:12 */
      4 | export const createAxiosError = (response: AxiosResponse): AxiosError =>
    > 5 |   new AxiosError(
        |   ^
      6 |     `Request failed with status code ${response.status}`,
      7 |     [AxiosError.ERR_BAD_REQUEST, AxiosError.ERR_BAD_RESPONSE][Math.floor(response.status / 100) - 4],
      8 |     response.config,

      at createAxiosError (clis/gpt/src/createAxiosError.ts:5:3)
      at askGPT (clis/gpt/src/gpt.ts:119:63)
      at Object.<anonymous> (clis/gpt/src/gpt.test.ts:66:20)

[kettanaito]

I'm closing this because MSW functions without issues in Node.js. If there are any issues in Bun, those are likely Bun issues with Node.js compatibility. I highly recommend you file those in Bun's repo to make the team aware. If you find something MSW-specific, feel free to update this thread.

[Valdermeyder]

Regarding your response above. It can be hard to draw a line between who should support what. Bun is not 100% compatible with NodeJs and maybe it shouldn't be. In both cases it would be great to have msw works in bun

Anyway, just wanted to share with you another error.
I'm trying to use Bun just as a testing runtime and the issue I spotted today is msw is failing on

458 |     const { status, statusText, headers, body } = mockedResponse;
459 |     this.response.statusCode = status;
          ^
TypeError: Attempted to assign to read only property.
      at respondWith (/Users/volodymyrhuzar/Sources/Twill/twill-email-templates/node_modules/@mswjs/interceptors/lib/node/chunk-YXLNUCS2.mjs:459:5)
      at /Users/volodymyrhuzar/Sources/Twill/twill-email-templates/node_modules/@mswjs/interceptors/lib/node/chunk-YXLNUCS2.mjs:342:9

bun - 1.0.26
"msw": "2.2.0"
Let me know if you are interested in more details

[kettanaito]

@VinceMalone, I can say with rather solid confidence that MSW will not ship anything specific to Bun. If you want to use MSW in Bun, you have to ensure Bun provides sufficient compatibility with Node.js (the http module and the global Fetch API, mainly).

Regarding the error, looks like a bug in Bun. The IncomingMessage.statusCode is not a readonly property. It's being assigned in the Interceptors library correctly.