feat(blame): Support custom rev_opts for blame

The `git blame` CLI offers a repeated `-C` option that can be used to detect
lines that move within/between files. While a slower operation, it yields more
accurate authorship reports.
https://git-scm.com/docs/git-blame#Documentation/git-blame.txt--Cltnumgt

While GitPython does enable passing custom kwargs to the command line `git`
invocation, the fact that kwargs is a dictionary (i.e. no duplicate keys) means
that there was no way to request the `-C` option in `git blame` more than once.

This commit adds an optional `rev_opts` parameter to the `blame` method which
accepts a list of strings to propagate to the CLI invocation of `git blame`. By
using a `List[str]` for `rev_opts`, users of GitPython can pass now the `-C`
option multiple times to get more detailed authorship reports from `git blame`.

Author: thehale

AUTHORS

@@ -49,4 +49,5 @@ Contributors are:
 -Julien Mauroy <pro.julien.mauroy _at_ gmail.com>
 -Patrick Gerard
 -Luke Twist <[email protected]>
+-Joseph Hale <me _at_ jhale.dev>
 Portions derived from other open source works and are clearly marked.

git/repo/base.py

@@ -950,7 +950,7 @@ def blame_incremental(self, rev: str | HEAD, file: str, **kwargs: Any) -> Iterat
             )
 
     def blame(
-        self, rev: Union[str, HEAD], file: str, incremental: bool = False, **kwargs: Any
+        self, rev: Union[str, HEAD], file: str, incremental: bool = False, rev_opts: Optional[List[str]]=None, **kwargs: Any
     ) -> List[List[Commit | List[str | bytes] | None]] | Iterator[BlameEntry] | None:
         """The blame information for the given file at the given revision.
 
@@ -962,8 +962,8 @@ def blame(
             of appearance."""
         if incremental:
             return self.blame_incremental(rev, file, **kwargs)
-
-        data: bytes = self.git.blame(rev, "--", file, p=True, stdout_as_string=False, **kwargs)
+        rev_opts = rev_opts or []
+        data: bytes = self.git.blame(rev, *rev_opts, "--", file, p=True, stdout_as_string=False, **kwargs)
         commits: Dict[str, Commit] = {}
         blames: List[List[Commit | List[str | bytes] | None]] = []
 

test/test_repo.py

@@ -553,6 +553,13 @@ def test_blame_complex_revision(self, git):
         self.assertEqual(len(res), 1)
         self.assertEqual(len(res[0][1]), 83, "Unexpected amount of parsed blame lines")
 
+    @mock.patch.object(Git, "_call_process")
+    def test_blame_accepts_rev_opts(self, git):
+        res = self.rorepo.blame("HEAD", "README.md", rev_opts=["-M", "-C", "-C"])
+        expected_args = ['blame', 'HEAD', '-M', '-C', '-C', '--', 'README.md']
+        for idx, arg in enumerate(expected_args):
+            self.assertEqual(git.call_args.args[idx], arg)
+
     @skipIf(
         HIDE_WINDOWS_KNOWN_ERRORS and Git.is_cygwin(),
         """FIXME: File "C:\\projects\\gitpython\\git\\cmd.py", line 671, in execute