fix files list on file rename

[teknoraver]

GitPython parses the output of git diff --no-renames to get the files changed in a commit.
This breaks when a commit contains a file rename, because the output of git diff is different than expected.
This is the output of a normal commit:

$ git diff --numstat 6ab9810cfe6c^ 6ab9810cfe6c
5 2 drivers/clk/zynqmp/divider.c

And this a commit containing a rename:

$ git diff --numstat db401875f438^ db401875f438
1 1 tools/testing/selftests/drivers/net/mlxsw/{spectrum-2 => }/devlink_trap_tunnel_ipip6.sh

This can be triggered by this code:

forcommitinrepo.iter_commits():
print(commit.hexsha)
forfileincommit.stats.files:
print(file)

Which will print for the normal commit:

6ab9810cfe6c8f3d8b8750c827d7870abd3751b9
'drivers/clk/zynqmp/divider.c'

And when there is a rename:

db401875f438168c5804b295b93a28c7730bb57a
('tools/testing/selftests/drivers/net/mlxsw/{spectrum-2 => '
'}/devlink_trap_tunnel_ipip6.sh')

Fix this by pasing the --no-renames option to git diff which ignores renames and print the same output as if the file was deleted from the old path and created in the new one:

$ git diff --numstat --no-renames db401875f438^ db401875f438
250 0 tools/testing/selftests/drivers/net/mlxsw/devlink_trap_tunnel_ipip6.sh
0 250 tools/testing/selftests/drivers/net/mlxsw/spectrum-2/devlink_trap_tunnel_ipip6.sh

[Byron]

Thanks a lot!

It should be straightforward to add a test that motivates this changes. The test-suite uses fixture files which could be derived from an example repository.

With a test that fails without this change, the fix can be merged.

Thank you

[teknoraver]

@Byron done, and I rewrote the commit message using GitPython hashes, so is simpler for anyone to test

[Byron]

Thanks a lot, this looks like the way to go!

Instead of checking what it shouldn't be (which is a huge set of possible values), could you instead check what it should be? How does a rename look like with the current interface, I'd be very interested to see that.

For posterity, here is what git thinks about the commit being used in the test:

commit 185d847ec7647fd2642a82d9205fb3d07ea71715
Author: Dominic <<redacted>@gmail.com>
Date: Mon Jul 12 17:02:21 2021 +0100
Update and rename test_pytest.yml to Future.yml
diff --git a/.github/workflows/test_pytest.yml b/.github/workflows/Future.yml
similarity index 92%
rename from .github/workflows/test_pytest.yml
rename to .github/workflows/Future.yml
index 627e720f..39146533 100644
--- a/.github/workflows/test_pytest.yml+++ b/.github/workflows/Future.yml@@ -5,7 +5,9 @@ name: Future
on:
push:
- branches: [main]+ branches: [ main ]+ pull_request:+ branches: [ main ]
jobs:
build:

[teknoraver]

This is the output of git show, gitpython does git diff --numstat $commit^ $commit which gives:

3 1 .github/workflows/{test_pytest.yml => Future.yml}

And with --no-renames added:

57 0 .github/workflows/Future.yml
0 55 .github/workflows/test_pytest.yml

[Byron]

Thanks a million, that is what I had in mind.

Thanks again for contributing!