error on add/import for implicit branch main

[KiaraGrouwstra]

using npins 0.2.4, npins import-flake...

works for inputs with implicit branch master:

    flake-compat.url = "github:edolstra/flake-compat";

[INFO ] Importing flake-compat

yet for inputs with implicit branch main fails:

    flake-parts.url = "github:hercules-ci/flake-parts";

[INFO ] Importing flake-parts
[ERROR] Failed to import pin 'flake-parts'
[ERROR] Couldn't fetch the latest commit
[ERROR]         git ls-remote output is empty. Are you sure 'refs/heads/master' exists? Note: If you want to tag a revision, you need to also specify a branch ('--branch').

something similar happens when adding such entries separately (without specifying branch):

npins add github hercules-ci flake-parts
[INFO ] Adding 'flake-parts' …
Error: Failed to fully initialize the pin

Caused by:
    Repository has no matching release tags

(a similar symptom also seemed reported at #100 (comment))

expected behavior: either default branch should just work

[piegamesde]

CC @stuebinm

[stuebinm]

oh dear.

afaict, there's two levels of unexpected things here: when I first wrote the flake importer, I assumes Nix would default to master rather than the repository's default branch, and that causes your npins import-flake to fail. Here, at least, the culprit is obvious, as is the fix: npins should run git ls-remote --symref <url> HEAD to find the default branch, if none was given as an argument. Perhaps I'll find the time to fix that soon-ish, if nobody else does (but I'm a bit tight on free time currently, so no outright promises).

The second error is unrelated, subtler, and (to me) much more surprising: npins is looking for a release tag, rather than a branch, and finding none (which is, as such, correct, as that repository has none, whereas flake-compat does, and hence for that this works). But I'm not sure if this is also the intended behaviour?

[piegamesde]

Let's focus on the import-flake issue, as in my eyes the failure of npins add github hercules-ci flake-parts is correct: npins add looks for releases unless a branch is specified. The UX of that may be changed of course, but to me things are working as intended..

[stuebinm]

(just in case it got missed: i opened a PR for this #114 — @KiaraGrouwstra can you try if it works for you?)

[KiaraGrouwstra]

@stuebinm thanks, #114 addresses this! 😌