I've been testing out an Action I was building today and having issues when verifying a step to publish the package to the GitHub Package Registry, which instead attempts to publish the package to the original NPM Registry:

https://github.com/JamesMGreene/test-repo/runs/199833215

After trying to track down the issue for longer than I care to mention as I went down a few incorrect rabbit holes, I believe the root cause is pretty simple: my GitHub username has uppercase letters in it but my NPM scoped package name, by necessity for validation, is all lowercased.

This creates a casing mismatch between the .npmrc file contents that get generated by the setup-node@v1 Action and the scope used by npm publish in a later Step. Some highlights from the Workflow Run logs:

Luckily, the fix for this should also be pretty simple: to lowercase the repo owner's login scope that gets written to the .npmrc file. 👌