git_index_read_tree() was exposing a parameter to provide the user with
a progress indicator. Unfortunately, due to the recursive nature of the
tree walk, the maximum number of items to process was unknown. Thus,
the indicator was only counting processed entries, without providing
any information how the number of remaining items.
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.
Renamed git_checkout_index to what it really was,
and removed duplicate code from clone.c. Added
git_checkout_ref, which updates HEAD and hands off
to git_checkout_head.
Added tests for the options the caller can pass to
git_checkout_*.
