[RFC PATCH 0/7] Fix `git clean` with pathspecs

Sometimes, multiple `git clean $ARGS` invocations (with the exact same flags and parameters for each invocation) are needed to properly clean out the desired files. Sometimes, `git clean $PATHS` just refuses to clean the files it was explicitly told to clean. This patch series aims to address these (very old) problems.

I was made aware of the problems when a user brought to me the
following testcase:
    mkdir d{1,2}
    touch d{1,2}/ut
    touch d1/t
    git add d1/t
With this setup, the user would need to run
    git clean -ffd */ut
twice to delete both ut files.  Digging further, I found multiple
interesting variants.

However, I am still slightly unsure of what the correct behavior is
supposed to be for one particular case, namely, if the clean command
were instead:
    git clean -f '*ut'
(note that the glob is quoted to protect from shell expansion, and
that the -d option was removed), should the files still be cleaned?  I
assumed yes and implemented that in patches 5-6, but the commit message
discusses this case, and patch 7 exists to change the implementation
to answer this question with a 'no'.  Patch 7 should NOT should not be
accepted as-is -- it should either be dropped or squashed into earlier
commits, but which depends on the desired behavior.

Patches 1-2 are almost independent one-line fixes that could be submitted independently. However, if we decide to keep the changes from patch 7, then this series does depend on patch 2 for the tests to pass.

Patch 3 adds four new testcases covering the variants I noticed.

Patch 4 fixes clean with explicit pathspecs and the -d option.

Patches 5-7 fixes clean with explicit pathspecs without the -d option.

Elijah Newren (7):
  dir.c: Fix typo in comment
  dir.c: fix off-by-one error in match_pathspec_item
  t7300: Add some testcases showing failure to clean specified pathspecs
  dir: Directories should be checked for matching pathspecs too
  dir: Make the DO_MATCH_SUBMODULE code reusable for a non-submodule
    case
  dir: If our pathspec might match files under a dir, recurse into it
  If we do not want globs to recurse into subdirs without -d...

 dir.c            | 23 +++++++++++++++--------
 dir.h            |  5 +++--
 t/t7300-clean.sh | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 50 insertions(+), 10 deletions(-)