This is a significant reorganization of the diff code to break it
into a set of more clearly distinct files and to document the new
organization. Hopefully this will make the diff code easier to
understand and to extend.
This adds a new `git_diff_driver` object that looks of diff driver
information from the attributes and the config so that things like
function content in diff headers can be provided. The full driver
spec is not implemented in the commit - this is focused on the
reorganization of the code and putting the driver hooks in place.
This also removes a few #includes from src/repository.h that were
overbroad, but as a result required extra #includes in a variety
of places since including src/repository.h no longer results in
pulling in the whole world.
* Rework GIT_DIRREMOVAL values to GIT_RMDIR flags, allowing
combinations of flags
* Add GIT_RMDIR_EMPTY_PARENTS flag to remove parent dirs that
are left empty after removal
* Add GIT_MKDIR_VERIFY_DIR to give an error if item is a file,
not a dir (previously an EEXISTS error was ignored, even for
files) and enable this flag for git_futils_mkpath2file call
* Improve accuracy of error messages from git_futils_mkdir
This started as a complex new test for checkout going through the
"typechanges" test repository, but that revealed numerous issues
with checkout, including:
* complete failure with submodules
* failure to create blobs with exec bits
* problems when replacing a tree with a blob because the tree
"example/" sorts after the blob "example" so the delete was
being processed after the single file blob was created
This fixes most of those problems and includes a number of other
minor changes that made it easier to do that, including improving
the TYPECHANGE support in diff/status, etc.
