When showing copy information because we are duplicating contents,
for example, when performing a `diff --find-copies-harder -M100 -B100`,
then show copy from/to lines in a patch, and do not show context.
Ensure that we can also parse such patches.
Avoid declaring old-style functions without any parameters.
Functions not accepting any parameters should be declared with
`void fn(void)`. See ISO C89 $3.5.4.3.
Read a tree into an index using `git_index_read_index` (by reading
a tree into a new index, then reading that index into the current
index), then write the index back out, ensuring that our new index
is treesame to the tree that we read.
Test with some postimages that actually grow/shrink from the
original, adding new lines or removing them. (Also do so without
context to ensure that we can add/remove from a non-zero part of
the line vector.)
Parse values up to and including `\377` (`0xff`) when unquoting.
Print octal values as an unsigned char when quoting, lest `printf`
think we're talking about negatives.
Patches can now come from a variety of sources - either internally
generated (from diffing two commits) or as the results of parsing
some external data.
When we are provided some input buffer (with a length) to inflate,
and it contains more data than simply the deflated data, fail.
zlib will helpfully tell us when it is done reading (via Z_STREAM_END),
so if there is data leftover in the input buffer, fail lest we
continually try to inflate it.
Handle the application of binary patches. Include tests that
produce a binary patch (an in-memory `git_patch` object),
then enusre that the patch applies correctly.
Instead of going through the usual steps of reading a tree recursively
into an index, modifying it and writing it back out as a tree, introduce
a function to perform simple updates more efficiently.
`git_tree_create_updated` avoids reading trees which are not modified
and supports upsert and delete operations. It is not as versatile as
modifying the index, but it makes some common operations much more
efficient.
`test_commit_commit__create_initial_commit_parent_not_current` was not correctly
testing that `HEAD` was not changed. Now we grab the oid that it was pointing to
before the call to `git_commit_create` and the oid that it's pointing to afterwards
and compare those.
