Grouse doesn't support Hugo themes which use GitInfo

[shah]

I'm using an out of the box example site with the Google Docsy theme. In each version running "hugo serve" or "hugo" builds properly. When I try to use grouse, I get the following:

ERROR 2019/12/22 18:38:19 Failed to read Git log: fatal: not a git repository (or any of the parent directories): .git

I'm not sure what I could be doing wrong so I was hoping to get some help. Here's my debug log.

❯ grouse --debug b616a47158aaf6459119bafa56ad39e7773f7f0b master
Computing diff between revisions b616a47158aaf6459119bafa56ad39e7773f7f0b (b616a47) and master (637d5ad)
Building revision b616a47158aaf6459119bafa56ad39e7773f7f0b (b616a47)…
2019/12/22 18:38:12 Checking out b616a47158aaf6459119bafa56ad39e7773f7f0b (b616a47) to /tmp/grouse-diff361430417/source/b616a47158aaf6459119bafa56ad39e7773f7f0b…
2019/12/22 18:38:12 Found submodules file, figuring out where to source the submodule contents from
2019/12/22 18:38:12 Found commit for submodule in worktree.
2019/12/22 18:38:12 Found submodules file, figuring out where to source the submodule contents from
2019/12/22 18:38:12 Found commit for submodule in worktree.
2019/12/22 18:38:13 Found commit for submodule in worktree.
2019/12/22 18:38:19 …done checking out.
2019/12/22 18:38:19 Running command
> hugo --destination=/tmp/grouse-diff361430417/output
(from directory /tmp/grouse-diff361430417/source/b616a47158aaf6459119bafa56ad39e7773f7f0b)
Building sites … ERROR 2019/12/22 18:38:19 Failed to read Git log: fatal: not a git repository (or any of the parent directories): .git
Total in 1571 ms
Error: Error building site: logged 1 error(s)
Error: Building at commit b616a47158aaf6459119bafa56ad39e7773f7f0b (b616a47) failed: exit status 255

[capnfabs]

Hey @shah! Thanks for filing the report about this, and for all the info you provided; it's very helpful.

So - the issue here is that:

• The Docsy theme uses Hugo's Git Info Variables to display modification timestamps / commit info for each page
• Grouse doesn't work with sites that use Hugo's Git Info Variables. Grouse copies Hugo source files to a temporary working directory and runs the build from there. This means that there isn't .git directory copied over, and so the system git used by hugo can't load any info (which is the source of the error message in the build step).

I was super unsure of the decision to roll my own checkout code when I released Grouse (I discuss it briefly here), and I think at some point in the next month, I'll re-work the code-checkout system to use git worktree instead, which should fix the Hugo GitInfo support as well.

In the meantime, I'll rename this issue accordingly and keep you updated here when I make the requisite changes.