This plugs in the three basic similarity strategies for handling
whitespace via internal use of the pluggable API. In so doing, I
realized that the use of git_buf in the hashsig API was not needed
and actually just made it harder to use, so I tweaked that API as
well.
Note that the similarity metric is still not hooked up in the
find_similarity code - this is just setting out the function that
will be used.
This moves the similarity metric code out of buf_text and into a
new file. Also, this implements a different approach to similarity
measurement based on a Rabin-Karp rolling hash where we only keep
the top 100 and bottom 100 hashes. In theory, that should be
sufficient samples to given a fairly accurate measurement while
limiting the amount of data we keep for file signatures no matter
how large the file is.
This adds a new `git_buf_text_hashsig` type and functions to
generate these hash signatures and compare them to give a
similarity score. This can be plugged into diff similarity
scoring.
The recent changes with git_treebuilder_entrycount point out that
the test coverage for git_treebuilder_remove and
git_treebuilder_entrycount is completely absent. This adds tests.
The cppcheck static analyzer generates warnings for a bunch of
places in the libgit2 code base. All the ones fixed in this
commit are actually false positives, but I've reorganized the
code to hopefully make it easier for static analysis tools to
correctly understand the structure. I wouldn't do this if I
felt like it was making the code harder to read or worse for
humans, but in this case, these fixes don't seem too bad and will
hopefully make it easier for better analysis tools to get at any
real issues.
The callback will be called for each file, just before the `git_delta_t` gets inserted into the diff list.
When the callback:
- returns < 0, the diff process will be aborted
- returns > 0, the delta will not be inserted into the diff list, but the diff process continues
- returns 0, the delta is inserted into the diff list, and the diff process continues
A leading slash confuses the name normalization code when the flags
include ALLOW_ONELEVEL. Catch this case in particular to avoid
triggering an assertion in the uppercase check which expects us not to
pass it an empty string.
The existing tests don't catch this as they simply use the NORMAL
flag.
This fixes#1300.
