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get_provisional_directory_renames() has code to detect directories being
evenly split between different locations. However, as noted previously,
if there are no new files added to that directory that was split evenly,
our inability to determine where the directory was renamed to doesn't
matter since there are no new files to try to move into the new
location. Unfortunately, that code is unaware of whether there are new
files under the directory in question and we just ignore that, causing
us to fail t6423 test 2b but pass test 2a; turn off the error for now,
swapping which tests pass and fail.
The motivating reason for switching this off as a temporary measure is
that as we add optimizations, we'll start looking at only subsets of
renames, and subsets of renames can start switching the result we get
when this error is (wrongly) on. Once we get enough optimizations,
however, we can prevent that code from even running when there are no
new files added to the relevant directory, at which point we can revert
this commit and then both testcases 2a and 2b will pass simultaneously.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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When a series of merges was performed (such as for a rebase or series of
cherry-picks), only the data structures allocated by the final merge
operation were being freed. The problem was that while picking out
pieces of merge-ort to upstream, I previously misread a certain section
of merge_start() and assumed it was associated with a later
optimization. Include that section now, which ensures that if there was
a previous merge operation, that we clear out result->priv and then
re-use it for opt->priv, and otherwise we allocate opt->priv.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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* en/ort-directory-rename: (28 commits)
merge-ort: fix a directory rename detection bug
merge-ort: process_renames() now needs more defensiveness
merge-ort: implement apply_directory_rename_modifications()
merge-ort: add a new toplevel_dir field
merge-ort: implement handle_path_level_conflicts()
merge-ort: implement check_for_directory_rename()
merge-ort: implement apply_dir_rename() and check_dir_renamed()
merge-ort: implement compute_collisions()
merge-ort: modify collect_renames() for directory rename handling
merge-ort: implement handle_directory_level_conflicts()
merge-ort: implement compute_rename_counts()
merge-ort: copy get_renamed_dir_portion() from merge-recursive.c
merge-ort: add outline of get_provisional_directory_renames()
merge-ort: add outline for computing directory renames
merge-ort: collect which directories are removed in dirs_removed
merge-ort: initialize and free new directory rename data structures
merge-ort: add new data structures for directory rename detection
merge-ort: add implementation of type-changed rename handling
merge-ort: add implementation of normal rename handling
merge-ort: add implementation of rename collisions
...
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As noted in commit 902c521a35 ("t6423: more involved directory rename
test", 2020-10-15), when we have a case where
* dir/subdir/ has several files
* almost all files in dir/subdir/ are renamed to folder/subdir/
* one of the files in dir/subdir/ is renamed to folder/subdir/newsubdir/
* the other side of history (that doesn't do the renames) adds a
new file to dir/subdir/
Then for the majority of the file renames, the directory rename of
dir/subdir/ -> folder/subdir/
is actually not represented that way but as
dir/ -> folder/
We also had one rename that was represented as
dir/subdir/ -> folder/subdir/newsubdir/
Now, since there's a new file in dir/subdir/, where does it go? Well,
there's only one rule for dir/subdir/, so the code previously noted that
this rule had the "majority" of the one "relevant" rename and thus
erroneously used it to place the file in folder/subdir/newsubdir/. We
really want the heavy weight associated with dir/ -> folder/ to also be
treated as dir/subdir/ -> folder/subdir/, so that we correctly place the
file in folder/subdir/.
Add a bunch of logic to make sure that we use all relevant renamings in
directory rename detection.
Note that testcase 12f of t6423 still fails after this, but it gets
further than merge-recursive does. There are some performance related
bits in that testcase (the region_enter messages) that do not yet
succeed, but the rest of the testcase works after this patch.
Subsequent patch series will fix up the performance side.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Since directory rename detection adds new paths to opt->priv->paths and
removes old ones, process_renames() needs to now check whether
pair->one->path actually exists in opt->priv->paths instead of just
assuming it does.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This function roughly follows the same outline as the function of the
same name from merge-recursive.c, but the code diverges in multiple
ways due to some special considerations:
* merge-ort's version needs to update opt->priv->paths with any new
paths (and opt->priv->paths points to struct conflict_infos which
track quite a bit of metadata for each path); merge-recursive's
version would directly update the index
* merge-ort requires that opt->priv->paths has any leading directories
of any relevant files also be included in the set of paths. And
due to pointer equality requirements on merged_info.directory_name,
we have to be careful how we compute and insert these.
* due to the above requirements on opt->priv->paths, merge-ort's
version starts with a long comment to explain all the special
considerations that need to be handled
* merge-ort can use the full data stored in opt->priv->paths to avoid
making expensive get_tree_entry() calls to regather the necessary
data.
* due to messages being deferred automatically in merge-ort, this is
the best place to handle conflict messages whereas in
merge-recursive.c they are deferred manually so that processing of
entries does all the printing
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Due to the string-equality-iff-pointer-equality requirements placed on
merged_info.directory_name, apply_directory_rename_modifications() will
need to have access to the exact toplevel directory name string pointer
and can't just use a new empty string. Store it in a field that we can
use.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This is copied from merge-recursive.c, with minor tweaks due to:
* using strmap API
* merge-ort not using the non_unique_new_dir field, since it'll
obviate its need entirely later with performance improvements
* adding a new path_in_way() function that uses opt->priv->paths
instead of doing an expensive tree_has_path() lookup to see if
a tree has a given path.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This is copied from merge-recursive.c, with minor tweaks due to using strmap
API and the fact that it can use opt->priv->paths to get all pathnames that
exist instead of taking a tree object.
This depends on a new function, handle_path_level_conflicts(), which
just has a placeholder die-not-yet-implemented implementation for now; a
subsequent patch will implement it.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Both of these are copied from merge-recursive.c, with just minor tweaks
due to using strmap API and not having a non_unique_new_dir field.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This is nearly a wholesale copy of compute_collisions() from
merge-recursive.c, and the logic remains the same, but it has been
tweaked slightly due to:
* using strmap.h API (instead of direct hashmaps)
* allocation/freeing of data structures were done separately in
merge_start() and clear_or_reinit_internal_opts() in an earlier
patch in this series
* there is no non_unique_new_dir data field in merge-ort; that will
be handled a different way
It does depend on two new functions, apply_dir_rename() and
check_dir_renamed() which were introduced with simple
die-not-yet-implemented shells and will be implemented in subsequent
patches.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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collect_renames() is similar to merge-recursive.c's get_renames(), but
lacks the directory rename handling found in the latter. Port that code
structure over to merge-ort. This introduces three new
die-not-yet-implemented functions that will be defined in future
commits.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This is modelled on the version of handle_directory_level_conflicts()
from merge-recursive.c, but is massively simplified due to the following
factors:
* strmap API provides simplifications over using direct hashmap
* we have a dirs_removed field in struct rename_info that we have an
easy way to populate from collect_merge_info(); this was already
used in compute_rename_counts() and thus we do not need to check
for condition #2.
* The removal of condition #2 by handling it earlier in the code also
obviates the need to check for condition #3 -- if both sides renamed
a directory, meaning that the directory no longer exists on either
side, then neither side could have added any new files to that
directory, and thus there are no files whose locations we need to
move due to such a directory rename.
In fact, the same logic that makes condition #3 irrelevant means
condition #1 is also irrelevant so we could drop this function.
However, it is cheap to check if both sides rename the same directory,
and doing so can save future computation. So, simply remove any
directories that both sides renamed from the list of directory renames.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This function is based on the first half of get_directory_renames() from
merge-recursive.c; as part of the implementation, factor out a routine,
increment_count(), to update the bookkeeping to track the number of
items renamed into new directories.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This function is based on merge-recursive.c's get_directory_renames(),
except that the first half has been split out into a not-yet-implemented
compute_rename_counts(). The primary difference here is our lack of the
non_unique_new_dir boolean in our strmap. The lack of that field will
at first cause us to fail testcase 2b of t6423; however, future
optimizations will obviate the need for that ugly field so we have just
left it out.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Port some directory rename handling changes from merge-recursive.c's
detect_and_process_renames() to the same-named function of merge-ort.c.
This does not yet add any use or handling of directory renames, just the
outline for where we start to compute them. Thus, a future patch will
add port additional changes to merge-ort's detect_and_process_renames().
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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* en/ort-conflict-handling:
merge-ort: add handling for different types of files at same path
merge-ort: copy find_first_merges() implementation from merge-recursive.c
merge-ort: implement format_commit()
merge-ort: copy and adapt merge_submodule() from merge-recursive.c
merge-ort: copy and adapt merge_3way() from merge-recursive.c
merge-ort: flesh out implementation of handle_content_merge()
merge-ort: handle book-keeping around two- and three-way content merge
merge-ort: implement unique_path() helper
merge-ort: handle directory/file conflicts that remain
merge-ort: handle D/F conflict where directory disappears due to merge
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* en/diffcore-rename:
diffcore-rename: remove unnecessary duplicate entry checks
diffcore-rename: accelerate rename_dst setup
diffcore-rename: simplify and accelerate register_rename_src()
t4058: explore duplicate tree entry handling in a bit more detail
t4058: add more tests and documentation for duplicate tree entry handling
diffcore-rename: reduce jumpiness in progress counters
diffcore-rename: simplify limit check
diffcore-rename: avoid usage of global in too_many_rename_candidates()
diffcore-rename: rename num_create to num_destinations
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Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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* en/merge-ort-3:
merge-ort: add implementation of type-changed rename handling
merge-ort: add implementation of normal rename handling
merge-ort: add implementation of rename collisions
merge-ort: add implementation of rename/delete conflicts
merge-ort: add implementation of both sides renaming differently
merge-ort: add implementation of both sides renaming identically
merge-ort: add basic outline for process_renames()
merge-ort: implement compare_pairs() and collect_renames()
merge-ort: implement detect_regular_renames()
merge-ort: add initial outline for basic rename detection
merge-ort: add basic data structures for handling renames
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Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Tweak unneeded recursion from a test framework helper function.
* es/perf-export-fix:
t/perf: avoid unnecessary test_export() recursion
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A 3-year old test that was not testing anything useful has been
corrected.
* fc/t6030-bisect-reset-removes-auxiliary-files:
test: bisect-porcelain: fix location of files
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"git worktree repair" learned to deal with the case where both the
repository and the worktree moved.
* es/worktree-repair-both-moved:
worktree: teach `repair` to fix multi-directional breakage
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The ORT merge strategy learned to synthesize virtual ancestor tree
by recursively merging multiple merge bases together, just like the
recursive backend has done for years.
* en/merge-ort-recursive:
merge-ort: implement merge_incore_recursive()
merge-ort: make clear_internal_opts() aware of partial clearing
merge-ort: copy a few small helper functions from merge-recursive.c
commit: move reverse_commit_list() from merge-recursive
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When a user does not tell "git pull" to use rebase or merge, the
command gives a loud message telling a user to choose between
rebase or merge but creates a merge anyway, forcing users who would
want to rebase to redo the operation. Fix an early part of this
problem by tightening the condition to give the message---there is
no reason to stop or force the user to choose between rebase or
merge if the history fast-forwards.
* fc/pull-merge-rebase:
pull: display default warning only when non-ff
pull: correct condition to trigger non-ff advice
pull: get rid of unnecessary global variable
pull: give the advice for choosing rebase/merge much later
pull: refactor fast-forward check
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More "ORT" merge strategy.
* en/merge-ort-2:
merge-ort: add modify/delete handling and delayed output processing
merge-ort: add die-not-implemented stub handle_content_merge() function
merge-ort: add function grouping comments
merge-ort: add a paths_to_free field to merge_options_internal
merge-ort: add a path_conflict field to merge_options_internal
merge-ort: add a clear_internal_opts helper
merge-ort: add a few includes
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The merge backend "done right" starts to emerge.
* en/merge-ort-impl:
merge-ort: free data structures in merge_finalize()
merge-ort: add implementation of record_conflicted_index_entries()
tree: enable cmp_cache_name_compare() to be used elsewhere
merge-ort: add implementation of checkout()
merge-ort: basic outline for merge_switch_to_result()
merge-ort: step 3 of tree writing -- handling subdirectories as we go
merge-ort: step 2 of tree writing -- function to create tree object
merge-ort: step 1 of tree writing -- record basenames, modes, and oids
merge-ort: have process_entries operate in a defined order
merge-ort: add a preliminary simple process_entries() implementation
merge-ort: avoid recursing into identical trees
merge-ort: record stage and auxiliary info for every path
merge-ort: compute a few more useful fields for collect_merge_info
merge-ort: avoid repeating fill_tree_descriptor() on the same tree
merge-ort: implement a very basic collect_merge_info()
merge-ort: add an err() function similar to one from merge-recursive
merge-ort: use histogram diff
merge-ort: port merge_start() from merge-recursive
merge-ort: add some high-level algorithm structure
merge-ort: setup basic internal data structures
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Various improvements to the codepath that writes out pack bitmaps.
* tb/pack-bitmap: (24 commits)
pack-bitmap-write: better reuse bitmaps
pack-bitmap-write: relax unique revwalk condition
pack-bitmap-write: use existing bitmaps
pack-bitmap: factor out 'add_commit_to_bitmap()'
pack-bitmap: factor out 'bitmap_for_commit()'
pack-bitmap-write: ignore BITMAP_FLAG_REUSE
pack-bitmap-write: build fewer intermediate bitmaps
pack-bitmap.c: check reads more aggressively when loading
pack-bitmap-write: rename children to reverse_edges
t5310: add branch-based checks
commit: implement commit_list_contains()
bitmap: implement bitmap_is_subset()
pack-bitmap-write: fill bitmap with commit history
pack-bitmap-write: pass ownership of intermediate bitmaps
pack-bitmap-write: reimplement bitmap writing
ewah: add bitmap_dup() function
ewah: implement bitmap_or()
ewah: make bitmap growth less aggressive
ewah: factor out bitmap growth
rev-list: die when --test-bitmap detects a mismatch
...
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The "--format=%(trailers)" mechanism gets enhanced to make it
easier to design output for machine consumption.
* ab/trailers-extra-format:
pretty format %(trailers): add a "key_value_separator"
pretty format %(trailers): add a "keyonly"
pretty-format %(trailers): fix broken standalone "valueonly"
pretty format %(trailers) doc: avoid repetition
pretty format %(trailers) test: split a long line
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"git fetch --recurse-submodules" fix (second attempt).
* pk/subsub-fetch-fix-take-2:
submodules: fix of regression on fetching of non-init subsub-repo
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Commit 25d5ea410f ("[PATCH] Redo rename/copy detection logic.",
2005-05-24) added a duplicate entry check on rename_src in order to
avoid segfaults; the code at the time was prone to double free()s and an
easy way to avoid it was just to turn off rename detection for any
duplicate entries. Note that the form of the check was modified two
commits ago in this series.
Similarly, commit 4d6be03b95 ("diffcore-rename: avoid processing
duplicate destinations", 2015-02-26) added a duplicate entry check
on rename_dst for the exact same reason -- the code was prone to double
free()s, and an easy way to avoid it was just to turn off rename
detection entirely. Note that the form of the check was modified in the
commit just before this one.
In the original code in both places, the code was dealing with
individual diff_filespecs and trying to match things up, instead of just
keeping the original diff_filepairs around as we do now. The
intervening change in structure has fixed the accounting problems and
the associated double free()s that used to occur, and thus we already
have a better fix. As such, we can remove the band-aid checks for
duplicate entries.
Due to the last two patches, the diffcore_rename() setup is no longer a
sizeable chunk of overall runtime. Thus, in a large rebase of many
commits with lots of renames and several optimizations to inexact rename
detection, this patch only speeds up the overall code by about half a
percent or so and is pretty close to the run-to-run variability making
it hard to get an exact measurement. However, with some trace2 regions
around the setup code in diffcore_rename() so that I can focus on just
it, I measure that this patch consistently saves almost a third of the
remaining time spent in diffcore_rename() setup.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Add some handling that explicitly considers collisions of the following
types:
* file/submodule
* file/symlink
* submodule/symlink
Leaving them as conflicts at the same path are hard for users to
resolve, so move one or both of them aside so that they each get their
own path.
Note that in the case of recursive handling (i.e. call_depth > 0), we
can just use the merge base of the two merge bases as the merge result
much like we do with modify/delete conflicts, binary files, conflicting
submodule values, and so on.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Code is identical for the function body in the two files, the call
signature is just slightly different in merge-ort than merge-recursive
as noted a couple commits ago.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This implementation is based on a mixture of print_commit() and
output_commit_title() from merge-recursive.c so that it can be used to
take over both functions.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Take merge_submodule() from merge-recursive.c and make slight
adjustments, predominantly around deferring output using path_msg()
instead of using merge-recursive's output() and show() functions.
There's also a fix for recursive cases (when call_depth > 0) and a
slight change to argument order for find_first_merges().
find_first_merges() and format_commit() are left unimplemented for
now, but will be added by subsequent commits.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Take merge_3way() from merge-recursive.c and make slight adjustments
based on different data structures (direct usage of object_id
rather diff_filespec, separate pathnames which based on our careful
interning of pathnames in opt->priv->paths can be compared with '!='
rather than 'strcmp').
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This implementation is based heavily on merge_mode_and_contents() from
merge-recursive.c, though it has some fixes for recursive merges (i.e.
when call_depth > 0), and has a number of changes throughout based on
slight differences in data structures and in how the functions are
called.
It is, however, based on two new helper functions -- merge_3way() and
merge_submodule -- for which we only provide die-not-implemented stubs
at this point. Future commits will add implementations of these
functions.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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In addition to the content merge (which will go in a subsequent commit),
we need to worry about conflict messages, placing results in higher
order stages in case of a df_conflict, and making sure the results are
placed in ci->merged.result so that they will show up in the working
tree. Take care of all that external book-keeping, moving the
simplistic just-take-HEAD code into the barebones handle_content_merge()
function for now. Subsequent commits will flesh out
handle_content_merge().
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Implement unique_path(), based on the one from merge-recursive.c. It is
simplified, however, due to: (1) using strmaps, and (2) the fact that
merge-ort lets the checkout codepath handle possible collisions with the
working tree means that other code locations don't have to.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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When a directory/file conflict remains, we can leave the directory where
it is, but need to move the information about the file to a different
pathname. After moving the file to a different pathname, we allow
subsequent process_entry() logic to handle any additional details that
might be relevant.
This depends on a new helper function, unique_path(), that dies with an
unimplemented error currently but will be implemented in a subsequent
commit.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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When one side has a directory at a given path and the other side of
history has a file at the path, but the merge resolves the directory
away (e.g. because no path within that directory was modified and the
other side deleted it, or because renaming moved all the files
elsewhere), then we don't actually have a conflict anymore. We just
need to clear away any information related to the relevant directory,
and then the subsequent process_entry() handling can handle the given
path.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Docfix.
* pb/doc-git-linkit-fix:
git.txt: fix typos in 'linkgit' macro invocation
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l10n for Git 2.30.0 round 2
* tag 'l10n-2.30.0-rnd2' of https://github.com/git-l10n/git-po:
l10n: zh_CN: for git v2.30.0 l10n round 1 and 2
l10n: zh_TW.po: v2.30.0 round 2 (1 untranslated)
l10n: pl.po: add translation and set team leader
l10n: pl.po: started Polish translation
l10n: de.po: Update German translation for Git 2.30.0
l10n: Update Catalan translation
l10n: bg.po: Updated Bulgarian translation (5037t)
l10n: fr.po v2.30.0 rnd 2
l10n: tr: v2.30.0-r2
l10n: sv.po: Update Swedish translation (5037t0f0u)
l10n: vi.po(5037t): v2.30.0 rnd 2
l10n: git.pot: v2.30.0 round 2 (1 new, 2 removed)
l10n: Update Catalan translation
l10n: fr.po: v2.30.0 rnd 1
l10n: fr.po Fix a typo
l10n: fr fix misleading message
l10n: tr: v2.30.0-r1
l10n: sv.po: Update Swedish translation (5038t0f0u)
l10n: git.pot: v2.30.0 round 1 (70 new, 45 removed)
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Translate 71 new messages (5037t0f0u) for git 2.30.0.
Reviewed-by: 依云 <lilydjwg@gmail.com>
Signed-off-by: Jiang Xin <worldhello.net@gmail.com>
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* 'l10n/zh_TW/201223' of github.com:l10n-tw/git-po:
l10n: zh_TW.po: v2.30.0 round 2 (1 untranslated)
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Elijah Newren
Junio C Hamano
Jiang Xin