While running oas-tools with jest for unit test cases it throws error: 'request for ./middleware/index.js is not yet fulfilled'

[vineetbro]

Describe the bug

I am using oas-tools 3.0.0 for my server and jest 29.0.0 for unit test case. My server runs as expected but when I ran my unit test cases it throws the error: 'request for ./middleware/index.js' is not yet fulfilled' and all test cases started failing. When I tried with oas-tools: 2.2.2 it works totally fine.

To Reproduce

Steps to reproduce the behavior:

1. initialize the server with @oas-tools/core
2. In jest configuration make sure the server files using @oas-tools/core is part of coverage.
3. Write a unit test case such that the 'initialize(express(), config)' is getting called.
4. Run the unit test cases using command: node --experimental-vm-modules node_modules/jest/bin/jest.js
5. See error

Expected behavior

The Oas must have initialized properly when running unit test cases using jest

Logs

2022-09-19T06:44:01.320Z - info: Specification file dereferenced
2022-09-19T06:44:01.402Z - info: Registered OASParams middleware
2022-09-19T06:44:01.403Z - info: Registered OASRequestValidator middleware
2022-09-19T06:44:01.403Z - info: Registered OASResponseValidator middleware
2022-09-19T06:44:01.403Z - info: Registered OASRouter middleware
2022-09-19T06:44:01.403Z - info: Registered OASSwagger middleware
2022-09-19T06:44:01.425Z - info: OAS Initialized successfully

● Test suite failed to run
request for './middleware/index.js' is not yet fulfilled
at Runtime.linkAndEvaluateModule (node_modules/jest-runtime/build/index.js:767:5)

Desktop (please complete the following information):

• OS: macOS Monteray 12.5
• Node Version: 14.18.1, 16.17.0

[alesancor1]

The initialize(app, cfg) function is asyncronous in v3.0.0, which may be the source of the problem. Are you using async/await to wait for the initialize promise to fulfill? I don't have much experience working with jest but with mocha for unit testing, take a look to OAS Tools tests, they may be similar to what you are trying to accomplish.

[vineetbro]

I have used the async/await to wait for initialization. The behaviour is such, with 'require(@oas-tools/core)' itself the error is thrown.

I am providing a zip file of project where the error can be reproduced. Here are the instructions to run and test the project

1. Download and extract the project
2. Run 'npm install' command
3. To start server run: make server
4. To execute unit test cases run: make test

Project ZIP
repro-server.zip:

Observation: The test cases will execute successfully but the Test Suit will fail because of the error:
● Test suite failed to run
request for './middleware/index.js' is not yet fulfilled
at Runtime.linkAndEvaluateModule (node_modules/jest-runtime/build/index.js:767:5)

[alesancor1]

This seems to be an issue with jest itself and the way it deals with ESM packages (see the issue here), so there's not much that can be done at the moment.

The core package will migrate to TS in the future and hopefully it will solve this problem due to the code being transpiled into CommonJS. For the time being, you could use mocha + c8 for coverage (I tested your repro-server using mocha and it works) or update to Node.js v18, which has an integrated testing library that I believe is pretty similar to jest.

[johonIngka]

@vineetbro did you find any solution or work arounds for this issue?

[vineetbro]

No, It is an issue with jest only. Right now I am using v2.2.2. The other option is to use mocha in place of jest