After doing further profiling, I found that a lot of time was
being spent attempting to insert hashes into the file hash
signature when using the rolling hash because the rolling hash
approach generates a hash per byte of the file instead of one
per run/line of data.
To optimize this, I decided to convert back to a run-based file
signature algorithm which would be more like core Git.
After changing this, a number of the existing tests started to
fail. In some cases, this appears to have been because the test
was coded to be too specific to the particular results of the file
similarity metric and in some cases there appear to have been bugs
in the core rename detection code where only by the coincidence
of the file similarity scoring were the expected results being
generated.
This renames all the variables in the core rename detection code
to be more consistent and hopefully easier to follow which made it
a bit easier to reason about the behavior of that code and fix the
problems that I was seeing. I think it's in better shape now.
There are a couple of tests now that attempt to stress test the
rename detection code and they are quite slow. Most of the time
is spent setting up the test data on disk and in the index. When
we roll out performance improvements for index insertion, it
should also speed up these tests I hope.
The performance improvements I introduced for rename detection
were not able to run successfully for tree-to-tree diffs because
the blob size was not known early enough and so the file signature
always had to be calculated nonetheless.
This change separates loading blobs into memory from calculating
the signature. I can't avoid having to load the large blobs into
memory, but by moving it forward, I'm able to avoid the signature
calculation if the blob won't come into play for renames.
Before the optimization commits, this test used to take about 20
seconds to run on my machine. Afterwards, there is still a couple
seconds of data setup, but the actual diff and rename detection
runs in a fraction of a second.
The git_reference_next API silently skips invalid references when
scanning the loose refs. The git_reference_next_name API should
skip the same ones even though it isn't creating the reference
object.
This adds a test with a an invalid loose reference and makes sure
that both APIs skip the same entries and generate the same results.
This restores a behavior that was accidentally lost during some
diff refactoring where an untracked directory that contains a .git
item should be treated as IGNORED, not as UNTRACKED. The submodule
code already detects this, but the diff code was not handling the
scenario right.
This also updates a number of existing tests that were actually
exercising the behavior but did not have the right expectations in
place. It actually makes the new
`test_diff_submodules__diff_ignore_options` test feel much better
because the "not-a-submodule" entries are now ignored instead of
showing up as untracked items.
Fixes#1697
This adds correct support for an equivalent to --ignore-submodules
in diff, where an actual ignore value can be passed to diff to
override the per submodule settings in the configuration.
This required tweaking the constants for ignore values so that
zero would not be used and could represent an unset option to the
diff. This was an opportunity to move the submodule values into
include/git2/types.h and to rename the poorly named DEFAULT values
for ignore and update constants to RESET instead.
Now the GIT_DIFF_IGNORE_SUBMODULES flag is exactly the same as
setting the ignore_submodules option to GIT_SUBMODULE_IGNORE_ALL
(which is actually a minor change from the old behavior in that
submodules will now be treated as UNMODIFIED deltas instead of
being left out totally - if you set GIT_DIFF_INCLUDE_UNMODIFIED).
This includes tests for the various new settings.
Submodules now expose an internal status API that allows diff to
get back the OID values from the submodule very easily and also
to avoiding caching issues and to override the ignore setting for
the submodule.
This adds a BARE option to git_repository_open_ext which allows
a fast open path that still knows how to read gitlinks and to
search for the actual .git directory from a subdirectory.
`git_repository_open_bare` is still simpler and faster, but having
a gitlink aware fast open is very useful for submodules where we
want to quickly be able to peek at the HEAD and index data without
doing any other meaningful repo operations.
This is probably not the final form of this change, but this is
a preliminary version of checking a timestamp to see if the cached
working directory HEAD OID matches the current. Right now, this
uses the timestamp on the index and is, like most of our timestamp
checking, subject to having only second accuracy.
The submodules code caches data about submodules in a way that
can cause problems. This adds some tests that try making various
modifications to the state of a submodule to see where we can
catch out problems in the submodule caching.
Right now, I've put in an extra git_submodule_reload_all so that
the test will pass, but with that commented out, the test fails.
I'm working on fixing the broken version of the test at which
point I'll commit the fix and delete the extra reload that makes
the test pass.
This controls for the diff.mnemonicprefix setting so that can't
break the tests. Also, this expands one test to emulate an
ObjectiveGit test more closely.
This adds an additional pathspec API that will match a pathspec
against a diff object. This is convenient if you want to handle
renames (so you need the whole diff and can't use the pathspec
constraint built into the diff API) but still want to tell if the
diff had any files that matched the pathspec.
When the pathspec is matched against a diff, instead of keeping
a list of filenames that matched, instead the API keeps the list
of git_diff_deltas that matched and they can be retrieved via a
new API git_pathspec_match_list_diff_entry.
There are a couple of other minor API extensions here that were
mostly for the sake of convenience and to reduce dependencies
on knowing the internal data structure between files inside the
library.
This is a simple bit vector object that is not resizable after
the initial allocation but can be of arbitrary size. It will
keep the bti vector entirely on the stack for vectors 64 bits
or less, and will allocate the vector on the heap for larger
sizes. The API is uniform regardless of storage location.
This is very basic right now and all the APIs are inline functions,
but it is useful for storing an array of boolean values.
This adds a new public API for compiling pathspecs and matching
them against the working directory, the index, or a tree from the
repository. This also reworks the pathspec internals to allow the
sharing of code between the existing internal usage of pathspec
matching and the new external API.
While this is working and the new API is ready for discussion, I
think there is still an incorrect behavior in which patterns are
always matched against the full path of an entry without taking
the subdirectories into account (so "s*" will match "subdir/file"
even though it wouldn't with core Git). Further enhancements are
coming, but this was a good place to take a functional snapshot.
The diff hunk context string that is returned to xdiff need not
be NUL terminated because the xdiff code just copies the number of
bytes that you report directly into the output. There was an off
by one in the diff driver code when the header context was longer
than the output buffer size, the output buffer length included
the NUL byte which was copied into the hunk header.
Fixes#1710
This option serves no benefit now that the git_status_list API
is available. It was of questionable value before and now it
would just be a bad idea to use it rather than the indexed API.
In both of these cases, the submodule data should still be loaded
just (obviously) without the data that comes from either the index
or the HEAD.
This fixes a bug in the orphaned head case.
There was a bug where submodules whose HEAD had not been moved
were being marked as having an UNMODIFIED delta record instead
of being left MODIFIED. This fixes that and fixes the tests to
notice if a submodule has been incorrectly marked as UNMODIFIED.
This adds the ability for checkout to write to a target directory
instead of having to use the working directory of the repository.
This makes it easier to do exports of repository data and the like.
This is similar to, but not quite the same as, the --prefix option
to `git checkout-index` (this will always be treated as a directory
name, not just as a simple text prefix).
As part of this, the workdir iterator was extended to take the
path to the working directory as a parameter and fallback on the
git_repository_workdir result only if it's not specified.
Fixes#1332
This fixes the checkout case when a file is modified between the
baseline and the target and yet missing in the working directory.
The logic for that case appears to have been wrong.
This also adds a useful checkout notify callback to the checkout
test helpers that will count notifications and also has a debug
mode to visualize what checkout thinks that it's doing.
