Quote Each Path in Both Refusals, So a Space or Comma Cannot Read as a Separator

Both messages joined raw paths with commas, so a single path holding a
comma read as two and one holding a space read ambiguously. That is worst
exactly when the message matters, since it fires on a path the caller did
not expect to be there.
One `quoted` helper serves both, rather than a repr at each site, since the
two messages drifting apart is the smaller version of the problem this PR
is about.
Two cases added, one per message.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: ptr727

scripts/prose_lint.py

@@ -199,6 +199,15 @@ def repo_prefix(root: Path) -> str:
 returnr.stdout.strip() ifr.returncode==0else''
 
 
+defquoted(paths) ->str:
+"""Paths as a sorted, quoted, comma-joined list for an error message.
+
+ Quoted because a path holding a space or a comma is indistinguishable from two paths once
+ joined, which makes the message unreadable exactly when it names something unexpected.
+ """
+return', '.join(repr(str(p)) forpinsorted(paths))
+
+
 defrepo_root(path: Path) ->str:
 """The repository top level containing `path`, or '' when git cannot say."""
 start=pathifpath.is_dir() elsepath.parent
@@ -1114,16 +1123,16 @@ def main(argv: list[str] | None = None) -> int:
 # `discover` reads a non-file, non-directory argument as `.`, so a typo scanned the caller's directory while the rule set anchored on the missing path's parent.
 absent= [pforpinscan_pathsifnotPath(p).exists()]
 ifabsent:
-print(f"error: requested path(s) do not exist: {', '.join(sorted(absent))}. Refusing "
-'rather than falling back to the current directory, which would scan one tree and '
-'choose the rule set from another.', file=sys.stderr)
+# Quoted, since a path holding a space or a comma is unreadable in a bare comma-joined list.
+print(f"error: requested path(s) do not exist: {quoted(absent)}. Refusing rather than "
+'falling back to the current directory, which would scan one tree and choose the '
+'rule set from another.', file=sys.stderr)
 return2
 git_roots= {foundforfoundin (repo_root(Path(p)) forpinscan_paths) iffound}
 iflen(git_roots) >1:
-print('error: the requested paths span more than one repository ('+
-', '.join(sorted(git_roots)) +'). Each declares its own workflow model, so no '
-'single rule set is correct for all of them. Run the gate once per repository.',
-file=sys.stderr)
+print(f'error: the requested paths span more than one repository ({quoted(git_roots)}). '
+'Each declares its own workflow model, so no single rule set is correct for all of '
+'them. Run the gate once per repository.', file=sys.stderr)
 return2
 # A file anchors on its own parent rather than on `.`, which is where the caller stands.
 ifgit_roots:

scripts/test_prose_lint.py

@@ -1868,6 +1868,21 @@ def test_a_path_that_does_not_exist_is_refused_rather_than_absorbed(self) -> Non
  [str(self.tmp/'no-such-dir'), '--check', 'home-path']))
 self.assertIn('do not exist', self.err.getvalue())
 
+deftest_a_path_holding_a_space_or_comma_is_quoted_in_the_refusal(self) ->None:
+"""Joined bare, one path with a comma in it reads as two paths and the message misleads."""
+awkward=self.tmp/'a dir, with comma'
+withmock.patch.object(prose_lint, 'repo_root', return_value=''):
+self.assertEqual(2, prose_lint.main([str(awkward), '--check', 'home-path']))
+self.assertIn(repr(str(awkward)), self.err.getvalue())
+
+deftest_repository_roots_are_quoted_in_the_span_refusal(self) ->None:
+spaced=self.tmp/'root with space'
+spaced.mkdir()
+withmock.patch.object(prose_lint, 'repo_root', side_effect=lambdap: str(Path(p))):
+self.assertEqual(2, prose_lint.main(
+ [str(self.release), str(spaced), '--check', 'home-path']))
+self.assertIn(repr(str(spaced)), self.err.getvalue())
+
 deftest_an_existing_path_is_not_refused_by_that_check(self) ->None:
 """The guard must not reject the ordinary case it sits in front of."""
 good=self.tmp/'good.md'