fix(install): store tags associated with package in node_modules dir

[nathanwhit]

Fixes #25998. Fixes #25928.

Originally I was just going to make this an error message instead of a panic, but once I got to a minimal repro I felt that this really should work.

The panic occurs when you have nodeModulesDir: manual (or a package.json present), and you have an npm package with a tag in your deno.json (see the spec test that illustrates this).

This code path only actually executes when trying to choose an appropriate package version from node_modules/.deno, so we should be able to fix it by storing some extra data at install time.

The fix proposed here is to repurpose the .initialized file that we store in node_modules to store the tags associated with a package. Basically, if you have a version requirement with a tag (e.g. npm:chalk@latest), when we set up the node_modules folder for that package, we store the tag (latest) in .initialized. Then, when doing BYONM resolution, if we have a version requirement with a tag, we read that file and check if the tag is present.

The downside is that we do more work when setting up node_modules. We could do this only when BYONM is enabled, but that would have the downside of needing to re-run deno install when you switch from auto -> manual, though maybe that's not a big deal.

[bartlomieju]

The fix proposed here is to repurpose the .initialized file that we store in node_modules to store the tags associated with a package. Basically, if you have a version requirement with a tag (e.g. npm:chalk@latest), when we set up the node_modules folder for that package, we store the tag (latest) in .initialized. Then, when doing BYONM resolution, if we have a version requirement with a tag, we read that file and check if the tag is present.

Will this not cause problem when switching to older Deno version? Ie. is this backwards compatible?

[nathanwhit]

The fix proposed here is to repurpose the .initialized file that we store in node_modules to store the tags associated with a package. Basically, if you have a version requirement with a tag (e.g. npm:chalk@latest), when we set up the node_modules folder for that package, we store the tag (latest) in .initialized. Then, when doing BYONM resolution, if we have a version requirement with a tag, we read that file and check if the tag is present.

Will this not cause problem when switching to older Deno version? Ie. is this backwards compatible?

Yeah it's backwards compatible, currently .intialized is just an empty file, so the contents don't matter to older versions.

[bartlomieju]

LGTM!