Jest not able to resolve subpaths with / only with \\

[BillyCottrell]

Hi,

So I am currently building an environment for AWS together with the SST framework.
I made a Lambda with an express server behind it and this is currently what I am trying to setup jest for.
This is my current file structure:

Root:
- packages
  - core
  - functions <-- location of my express server
- portal
- stacks

So inside my functions directory I have a separate package.json, tsconfig.json and jest.config.ts file.
Now my tests work but I am unable to access the core directory.
In my tsconfig I have the following path configured:

"paths": {
  "@packages/core/*": ["../core/src/*"]
}

I tried to add this inside my jest config like this:

moduleNameMapper: {
  "@packages/core/(.*)": "<rootDir>/../core/src/$1",
},

Which does work for paths like: @packages/core/controllers, but not when a subpath is added as it is unable to resolve it and gives the following error:

    Configuration error:

    Could not locate module @packages/core/src/utils/database mapped as:
    D:\test\aws\myProject\packages\core\src\$1.

    Please check your configuration for these entries:
    {
      "moduleNameMapper": {
        "/@packages\/core\/(.*)/": "D:\test\aws\myProject\packages\core\src\$1"
      },
      "resolver": undefined
    }

The only way I could get it to work was if I changed my import, from using "/" to using "\" as then it was able to resolve it without an issue. Probably because its trying to resolve the path like this:

D:\test\aws\myProject\packages\core\src\utils/database
                                             ^

Which obviously doesn't work.

So now my question is am I doing something wrong here do I need to change my configuration or do I just update my imports to use "\" instead?

FYI, I am using the following dependencies:

  "devDependencies": {
    "@types/aws-lambda": "^8.10.114",
    "@types/express": "^4.17.17",
    "@types/jest": "^29.5.3",
    "@types/node": "^18.15.5",
    "@types/passport": "^1.0.12",
    "@types/supertest": "^2.0.12",
    "jest": "^29.6.1",
    "sst": "^2.2.4",
    "supertest": "^6.3.3",
    "ts-jest": "^29.1.1"
  },
  "dependencies": {
    "body-parser": "^1.20.2",
    "cookie-parser": "^1.4.6",
    "cors": "^2.8.5",
    "express": "^4.18.2",
    "mongodb": "^5.3.0",
    "mongoose": "^7.1.1",
    "passport": "^0.6.0",
    "passport-local": "^1.0.0",
    "serverless-http": "^3.2.0"
  }

Hope someone can clear this out for me!

Thanks in advance!

Kind regards,

Billy