How do I find which packages are dependent on Angular versions higher than 6.x?

I'm on a project that is is utilizing Angular 5.x and I'm tasked to upgrade it to 6.x. After nearly 2 weeks now trying to figure out how all this works with NPM and unsuccessfully getting the upgrade to build due to what I believe are package errors, I'm at a complete loss.

I have wiped out the node_modules multiple times and reran this project but the ng build fails from what looks like package issues.

How can I find which packages are dependent on Angular versions higher than 6.x?

I've tried doing one package at a time but I'm missing something as it won't build. Errors vary from Observable not being found within some package or it is looking for the Angular 6 hack package.

The best solution that I was able to come up with is as follows

• Follow the update guide from Angular
• For each package that is defined in the package.json
• Execute the following commands
• • See outdated packages: npm outdated
• • Update the package.json file to match versions

Note: I would not just update the packages to the latest and greatest as their may be some dependency issue with doing a big version change. Instead follow the below approach.

• For all packages, executed the following commands
• • View the available version: npm view packageName versions --json
• • View the version dependencies: npm view packageName dependencies --json
• • View the version peerDependencies: npm view packageName peerDependencies --json
• • Update the package.json file to match highest version that goes with Angular 6.1.10

Maybe this was all unnecessary but not really knowing the ins and out of npm as well as Angular it is the best that I could come up with.

Everything is now updated from 5.x to 6.1.10 and npm install fully functions when I remove the node_modules folder, ng build compiles without errors, and the application is fully operational.