babel-jest module isn't found if not added directly

Hi guys, I noticed today that I cannot run tests anymore if I have setup Babel transpilation for JS files.

I get this error

● Validation Error:

  Module babel-jest in the transform option was not found.
         <rootDir> is: D:\Sources\smile80\libs\renderer

  Configuration Documentation:
  https://jestjs.io/docs/configuration.html

I checked my yarn.lock file and babel-jest is actually present in the file, but there’s no folder into node_modules, that may be the cause. Lately I upgraded to yarn 1.16.0, so I tried downgrading to 1.15.2, but with no results: same error.

If I add it as a direct dependency, it restarts working. I’m pretty confused right now, I checked my history and I’m pretty sure that 2 days ago I launched my tests without problems and without babel-jest as direct dependency.

[inlightmedia]

I ran into this when using yarn workspaces. One of my packages was using babel-jest for testing but when I added babel-jest to the package.json it would add to the repo’s root yarn.lock file and not to the node_modules folder of the package. In my jest transform I was referencing babel-jest like this:

transform: {
        "^.+\\.(js|jsx|ts|tsx)$": "./node_modules/.bin/babel-jest",
},

To fix, I just removed the relative path:

transform: {
        "^.+\\.(js|jsx|ts|tsx)$": "babel-jest",
},

[aManNamedJed]

@inlightmedia Not all heroes wear capes, or perhaps you do, in which case I like you even more. Thank you!