Relative path in a repo subdirectory not found when using hash symmetric difference

[dshemetov]

Describe the bug
Relative path in a repo subdirectory not found when using --revision=<hash>...<hash> but not when using --revision=origin/main....

To Reproduce
Steps to reproduce the behavior:

1. Clone this repository: https://github.com/dshemetov/darker-test
2. See the README.md in the repo for instructions

Expected behavior
The behavior between these should be consistent, I believe.

Environment (please complete the following information):

• OS: Ubuntu 20.04
• Python version 3.8, 3.10 (doesn't really matter)
• Darker version 1.7.2
• Black version 23.10.1

Steps before ready to implement:

• Reproduce
• Understand the reason
• Design a fix and update the description

[akaihola]

Hi @dshemetov,

Could you check whether your description is correct ("not found" in both cases)?

Relative path in a repo subdirectory not found when using --revision=... but not when using --revision=origin/main....

[dshemetov]

Hi @akaihola, thanks for looking into this. It'll take me a little time to remember the context here, but I'll try and verify soon.

[akaihola]

I just managed to reproduce this issue using your repository:

[/tmp/darker-test]$ darker --check -r a994113...origin/dev subdir
[/tmp/darker-test]$ darker --check -r a994113...origin/dev subdir/subsubdir
[/tmp/darker-test]$ cd subdir
[/tmp/darker-test/subdir]$ darker --check -r a994113...origin/dev subsubdir
argument PATH: Error: Path(s) 'subsubdir' do not exist in origin/dev

[akaihola]

To reproduce and understand this on the Git level:

[/tmp/darker-test]$ git cat-file -p origin/dev:subdir
100644 blob 6f1c2a548639ac49507a525b63597938878b2e6d	Makefile
100644 blob 921b47f1f8168d376ad41a120c1d79a4ab8fe5fa	requirements.txt
040000 tree adc767417cd500fe67e0add3ca9a71c670ca4b29	subsubdir

[/tmp/darker-test]$ git cat-file -p origin/dev:subdir/subsubdir
100644 blob 14c0d0b5e618b2921fceaee13f4965974d3f137a	file.py

[/tmp/darker-test]$ cd subdir

[/tmp/darker-test/subdir]$ git cat-file -p origin/dev:subsubdir
fatal: path 'subsubdir' does not exist in 'origin/dev'

[/tmp/darker/test/subdir]$ git cat-file -p origin/dev:subdir/subsubdir
100644 blob 14c0d0b5e618b2921fceaee13f4965974d3f137a	file.py

[/tmp/darker/test/subdir]$ git cat-file -p origin/dev:./subsubdir
100644 blob 14c0d0b5e618b2921fceaee13f4965974d3f137a	file.py

[/tmp/darker-test/subdir]$ cd subsubdir

[/tmp/darker-test/subdir/subsubdir]$ git cat-file -p origin/dev:./file.py
a = ["really", "really", "really","really",     "really", "really", "really", "really","really",  "really", "long", "line"] # add comment

So git cat-file seems to treat paths relative to repository root and not the current working directory – unless the path begins with ./

The fix then is to either prepend ./ to paths in the git cat-file call, or to always include all path elements starting from the repository root.

[akaihola]

@dshemetov would you like to accept the invite to become a collaborator on the Darker repository, and review the fix in PR #584?

[dshemetov]

Hey @akaihola, thanks for addressing this! I see you've already received a review and merged the fix, I will double check and confirm that the issue I had is resolved 👍

[akaihola]

thanks for addressing this! I see you've already received a review and merged the fix, I will double check and confirm that the issue I had is resolved

Glad @dshemetov if it helps! I hope my fix works. Path handling is a bit messy in Darker, could be simplified in the future...