How to resolve conflicting dependencies

Hi, I have an issue on build when I install react-aad-msal where the build script complains about conflicting versions of “babel-jest”. Running “npm ls babel-jest” gives the following:

Library: Dependency: react-aad-msal@0.4.1 | ±- babel-jest@22.4.4 react-scripts@2.1.3 `-- babel-jest@23.6.0

The suggested solution is to remove the babel-jest dependency from package.json but there’s no such thing in my package.json, it simply comes embedded as a dependency in the react-aad-msal library. Note I am using yarn not npm so don’t have switching to yarn as a possible solution.

So my next step was to try downloading the CRA sample project and adding react-aad-msal to it. This showed exactly the same dependency conflict when you run “npm ls babel-jest” BUT it then proceeds to build without any error! So my question is why does the build script complain in one situation but not in the other? And what sort of thing should I be trying next?

The full error on build is below…thanks

yarn run v1.12.1 $ set REACT_APP_ENV=dev&&react-scripts start There might be a problem with the project dependency tree. It is likely not a bug in Create React App, but something you need to fix locally. The react-scripts package provided by Create React App requires a dependency: “babel-jest”: “23.6.0” Don’t try to install it manually: your package manager does it automatically. However, a different version of babel-jest was detected higher up in the tree: …\node_modules\babel-jest (version: 22.4.4) Manually installing incompatible versions is known to cause hard-to-debug issues. If you would prefer to ignore this check, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project. That will permanently disable this message but you might encounter other issues.

To fix the dependency tree, try following the steps below in the exact order:

1. Delete package-lock.json (not package.json!) and/or yarn.lock in your project folder.
2. Delete node_modules in your project folder.
3. Remove “babel-jest” from dependencies and/or devDependencies in the package.json file in your project folder.
4. Run npm install or yarn, depending on the package manager you use. In most cases, this should be enough to fix the problem. If this has not helped, there are a few other things you can try:
5. If you used npm, install yarn (http://yarnpkg.com/) and repeat the above steps with it instead. This may help because npm has known issues with package hoisting which may get resolved in future versions.
6. Check if C:\ecp\ecpwebapplications\ecpexternal\node_modules\babel-jest is outside your project directory. For example, you might have accidentally installed something in your home folder.
7. Try running npm ls babel-jest in your project folder. This will tell you which other package (apart from the expected react-scripts) installed babel-jest.

If nothing else helps, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project. That would permanently disable this preflight check in case you want to proceed anyway.

P.S. We know this message is long but please read the steps above 😃 We hope you find them helpful!

[roberthchapman]

Thanks so much for the assistance, the solution is actually a lot simpler than what I thought I was meant to be trying. It’s just forcing all packages to use the same version, simple. And much more simple than the examples I could see. All I had to do was:

1. yarn remove react-aad-msal
2. add “resolutions”: { “jest”: “23.6.0”, “babel-jest”: “23.6.0” }, to package.json
3. yarn install
4. yarn add react-aad-msal

and that’s it!

[mrmckeb]

Thanks for the update @roberthchapman.