There are three conflict types that represent two (possibly entirely
unrelated) files colliding at the same location:
* add/add
* rename/add
* rename/rename(2to1)
These three conflict types already share more similarity than might be
immediately apparent from their description: (1) the handling of the
rename variants already involves removing any entries from the index
corresponding to the original file names[*], thus only leaving entries
in the index for the colliding path; (2) likewise, any trace of the
original file name in the working tree is also removed. So, in all
three cases we're left with how to represent two colliding files in both
the index and the working copy.
[*] Technically, this isn't quite true because rename/rename(2to1)
conflicts in the recursive (o->call_depth > 0) case do an "unrename"
since about seven years ago. But even in that case, Junio felt
compelled to explain that my decision to "unrename" wasn't necessarily
the only or right answer -- search for "Comment from Junio" in t6036 for
details.
My initial motivation for looking at these three conflict types was that
if the handling of these three conflict types is the same, at least in
the limited set of cases where a renamed file is unmodified on the side
of history where the file is not renamed, then a significant performance
improvement for rename detection during merges is possible. However,
while that served as motivation to look at these three types of
conflicts, the actual goal of this new function is to try to improve the
handling for all three cases, not to merely make them the same as each
other in that special circumstance.
=== Handling the working tree ===
The previous behavior for these conflict types in regards to the
working tree (assuming the file collision occurs at 'foo') was:
* add/add does a two-way merge of the two files and records it as 'foo'.
* rename/rename(2to1) records the two different files into two new
uniquely named files (foo~HEAD and foo~$MERGE), while removing 'foo'
from the working tree.
* rename/add records the two different files into two different
locations, recording the add at foo~$SIDE and, oddly, recording
the rename at foo (why is the rename more important than the add?)
So, the question for what to write to the working tree boils down to
whether the two colliding files should be two-way merged and recorded in
place, or recorded into separate files. As per discussion on the git
mailing lit, two-way merging was deemed to always be preferred, as that
makes these cases all more like content conflicts that users can handle
from within their favorite editor, IDE, or merge tool. Note that since
renames already involve a content merge, rename/add and
rename/rename(2to1) conflicts could result in nested conflict markers.
=== Handling of the index ===
For a typical rename, unpack_trees() would set up the index in the
following fashion:
old_path new_path
stage1: 5ca1ab1e 00000000
stage2: f005ba11 00000000
stage3: 00000000 b0a710ad
And merge-recursive would rewrite this to
new_path
stage1: 5ca1ab1e
stage2: f005ba11
stage3: b0a710ad
Removing old_path from the index means the user won't have to `git rm
old_path` manually every time a renamed path has a content conflict.
It also means they can use `git checkout [--ours|--theirs|--conflict|-m]
new_path`, `git diff [--ours|--theirs]` and various other commands that
would be difficult otherwise.
This strategy becomes a problem when we have a rename/add or
rename/rename(2to1) conflict, however, because then we have only three
slots to store blob sha1s and we need either four or six. Previously,
this was handled by continuing to delete old_path from the index, and
just outright ignoring any blob shas from old_path. That had the
downside of deleting any trace of changes made to old_path on the other
side of history. This function instead does a three-way content merge of
the renamed file, and stores the blob sha1 for that at either stage2 or
stage3 for new_path (depending on which side the rename came from). That
has the advantage of bringing information about changes on both sides and
still allows for easy resolution (no need to git rm old_path, etc.), but
does have the downside that if the content merge had conflict markers,
then what we store in the index is the sha1 of a blob with conflict
markers. While that is a downside, it seems less problematic than the
downsides of any obvious alternatives, and certainly makes more sense
than the previous handling. Further, it has a precedent in that when we
do recursive merges, we may accept a file with conflict markers as the
resolution for the merge of the merge-bases, which will then show up in
the index of the outer merge at stage 1 if a conflict exists at the outer
level.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Later patches in this series will modify file collision conflict
handling (e.g. from rename/add and rename/rename(2to1) conflicts) so
that multiply nested conflict markers can arise even before considering
conflicts in the virtual merge base. Including the virtual merge base
will provide a way to get triply (or higher) nested conflict markers.
This new way to get nested conflict markers will force the need for a
more general mechanism to extend the length of conflict markers in order
to differentiate between different nestings.
Along with this change to conflict marker length handling, we want to
make sure that we don't regress handling for other types of conflicts
with nested conflict markers. Add a more involved testcase using
merge.conflictstyle=diff3, where not only does the virtual merge base
contain conflicts, but its virtual merge base does as well (i.e. a case
with triply nested conflict markers). While there are multiple
reasonable ways to handle nested conflict markers in the virtual merge
base for this type of situation, the easiest approach that dovetails
well with the new needs for the file collision conflict handling is to
require that the length of the conflict markers increase with each
subsequent nesting.
Subsequent patches which change the rename/add and rename/rename(2to1)
conflict handling will modify the extra_marker_size flag appropriately
for their new needs.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a single file is renamed, it can also be modified, yielding the
possibility of that renamed file having content conflicts. If two
different such files are renamed into the same location, then two-way
merging those files may result in nested conflicts. Add a testcase that
makes sure we get this case correct, and uses different lengths of
conflict markers to differentiate between the different nestings.
Also add another case with an extra (i.e. third) level of conflict
markers due to using merge.conflictstyle=diff3 and the virtual merge
base also having conflicts present.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add testcases dealing with file collisions for the following types of
conflicts:
* add/add
* rename/add
* rename/rename(2to1)
All these conflict types simplify down to two files "colliding"
and should thus be handled similarly. This means that rename/add and
rename/rename(2to1) conflicts need to be modified to behave the same as
add/add conflicts currently do: the colliding files should be two-way
merged (instead of the current behavior of writing the two colliding
files out to separate temporary unique pathnames). Add testcases which
check this; subsequent commits will fix the conflict handling to make
these tests pass.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we converted a `git reset --hard` call in the original Unix shell
script to built-in code, we asked to reset the worktree and the index
and explicitly *not* to detach the HEAD. By mistake, though, we still
did. Let's fix this.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An unnamed colleague of Ævar Arnfjörð Bjarmason reported a breakage
where a `pull --rebase` (which did not really need to do anything but
stash, see that nothing was changed, and apply the stash again) also
detached the HEAD.
This patch adds a minimal reproducer for this regression.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When git.rc is compiled into git.res, the result is actually dependent
on the architecture. That is, you cannot simply link a 32-bit git.res
into a 64-bit git.exe.
Therefore, to allow 32-bit and 64-bit builds in the same directory, we
let git.res depend on GIT-PREFIX so that it gets recompiled when
compiling for a different architecture (this works because the exec path
changes based on the architecture: /mingw32/libexec/git-core for 32-bit
and /mingw64/libexec/git-core for 64-bit).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we see a time like "noon", we pass "12" to our date_time() helper,
which sets the hour to 12pm. If the current time is before noon, then we
wrap around to yesterday using date_yesterday(). But unlike the normal
calls to date_yesterday() from approxidate_alpha(), we pass a NULL "num"
parameter. Since c27cc94fad (approxidate: handle pending number for
"specials", 2018-11-02), that causes a segfault.
One way to fix this is by checking for NULL. But arguably date_time() is
abusing our helper by passing NULL in the first place (and this is the
only case where one of these "special" parsers is used this way). So
instead, let's have it just do the 1-day subtraction itself. It's still
just a one-liner due to our update_tm() helper.
Note that the test added here is a little funny, as we say "10am noon",
which makes the "10am" seem pointless. But this bug can only be
triggered when it the currently-parsed hour is before the special time.
The latest special time is "tea" at 1700, but t0006 uses a hard-coded
TEST_DATE_NOW of 1900. We could reset TEST_DATE_NOW, but that may lead
to confusion in other tests. Just saying "10am noon" makes this test
self-contained.
Reported-by: Carlo Arenas <carenas@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A git push process runs several processes during its run, but one
includes git send-pack which calls git pack-objects and passes
the known have/wants into stdin using object ids. However, the
default setting for core.warnAmbiguousRefs requires git pack-objects
to check for ref names matching the ref_rev_parse_rules array in
refs.c. This means that every object is triggering at least six
"file exists?" queries. When there are a lot of refs, this can
add up significantly! I observed a simple push spending three
seconds checking these paths.
The fix here is similar to 4c30d50 "rev-list: disable object/refname
ambiguity check with --stdin". While the get_object_list() method
reads the objects from stdin, turn warn_on_object_refname_ambiguity
flag (which is usually true) to false. Just for code hygiene, save
away the original at the beginning and restore it once we are done.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We usually just forward the --verify-signatures option along to
git-merge, and trust it to do the right thing. However, when we are on
an unborn branch (i.e., there is no HEAD yet), we handle this case
ourselves without even calling git-merge. And in this code path, we do
not respect the verification option at all.
It may be more maintainable in the long run to call git-merge for the
unborn case. That would fix this bug, as well as prevent similar ones in
the future. But unfortunately it's not easy to do. As t5520.3
demonstrates, there are some special cases that git-merge does not
handle, like "git pull .. master:master" (by the time git-merge is
invoked, we've overwritten the unborn HEAD).
So for now let's just teach git-pull to handle this feature.
Reported-by: Felix Eckhofer <felix@eckhofer.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When git-merge sees that we are on an unborn branch (i.e., there is no
HEAD), it follows a totally separate code path than the usual merge
logic. This code path does not know about verify_signatures, and so we
fail to notice bad or missing signatures.
This has been broken since --verify-signatures was added in efed002249
(merge/pull: verify GPG signatures of commits being merged, 2013-03-31).
In an ideal world, we'd unify the flow for this case with the regular
merge logic, which would fix this bug and avoid introducing similar
ones. But because the unborn case is so different, it would be a burden
on the rest of the function to continually handle the missing HEAD. So
let's just port the verification check to this special case.
Reported-by: Felix Eckhofer <felix@eckhofer.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The logic to implement "merge --verify-signatures" is inline in
cmd_merge(), but this site misses some cases. Let's extract the logic
into a function so we can call it from more places.
We'll move it to commit.[ch], since one of the callers (git-pull) is
outside our source file. This function isn't all that general (after
all, its main function is to exit the program) but it's not worth trying
to fix that. The heavy lifting is done by check_commit_signature(), and
our purpose here is just sharing the die() logic. We'll mark it with a
comment to make that clear.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our test scripts can now take the '-V' option as a synonym for the
'--verbose-log' option.
* sg/test-verbose-log:
test-lib: introduce the '-V' short option for '--verbose-log'
The "container" mode of TravisCI is going away. Our .travis.yml
file is getting prepared for the transition.
* ss/travis-ci-force-vm-mode:
travis-ci: no longer use containers
Windows port learned to use nano-second resolution file timestamps.
* js/mingw-ns-filetime:
mingw: implement nanosecond-precision file times
mingw: replace MSVCRT's fstat() with a Win32-based implementation
mingw: factor out code to set stat() data
Operations on promisor objects make sense in the context of only a
small subset of the commands that internally use the revisions
machinery, but the "--exclude-promisor-objects" option were taken
and led to nonsense results by commands like "log", to which it
didn't make much sense. This has been corrected.
* md/exclude-promisor-objects-fix:
exclude-promisor-objects: declare when option is allowed
Documentation/git-log.txt: do not show --exclude-promisor-objects
"git send-email" learned to disable SMTP authentication via the
"--smtp-auth=none" option, even when the smtp username is given
(which turns the authentication on by default).
* jw/send-email-no-auth:
send-email: explicitly disable authentication
The command line completion machinery (in contrib/) has been
updated to allow the completion script to tweak the list of options
that are reported by the parse-options machinery correctly.
* nd/completion-negation:
completion: fix __gitcomp_builtin no longer consider extra options
"git fetch" over protocol v2 into a shallow repository failed to
fetch full history behind a new tip of history that was diverged
before the cut-off point of the history that was previously fetched
shallowly.
* jt/upload-pack-v2-fix-shallow:
upload-pack: clear flags before each v2 request
upload-pack: make want_obj not global
upload-pack: make have_obj not global
Some codepaths failed to form a proper URL when .gitmodules record
the URL to a submodule repository as relative to the repository of
superproject, which has been corrected.
* sb/submodule-url-to-absolute:
submodule helper: convert relative URL to absolute URL if needed
"git repack" in a shallow clone did not correctly update the
shallow points in the repository, leading to a repository that
does not pass fsck.
* js/shallow-and-fetch-prune:
repack -ad: prune the list of shallow commits
shallow: offer to prune only non-existing entries
repack: point out a bug handling stale shallow info
The logic to determine the archive type "git archive" uses did not
correctly kick in for "git archive --remote", which has been
corrected.
* js/remote-archive-dwimfix:
archive: initialize archivers earlier
This helps format-patch gain completion for a couple new options,
notably --range-diff.
Since send-email completion relies on $__git_format_patch_options
which is now reduced, we need to do something not to regress
send-email completion.
The workaround here is implement --git-completion-helper in
send-email.perl just as a bridge to "format-patch --git-completion-helper".
This is enough to use __gitcomp_builtin on send-email (to take
advantage of caching).
In the end, send-email.perl can probably reuse the same info it passes
to GetOptions() to generate full --git-completion-helper output so
that we don't need to keep track of its options in git-completion.bash
anymore. But that's something for another boring day.
Helped-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The write_midx_large_offsets() function takes an array of object
entries, the number of entries in the array (nr_objects), and the number
of entries with large offsets (nr_large_offset). But we never actually
use nr_objects; instead we keep walking down the array and counting down
nr_large_offset until we've seen all of the large entries.
This is correct, but we can be a bit more defensive. If there were ever
a mismatch between nr_large_offset and the actual set of large-offset
objects, we'd walk off the end of the array.
Since we know the size of the array, we can use nr_objects to make sure
we don't walk too far.
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we define a parse-options callback, the flags we put in the option
struct must match what the callback expects. For example, a callback
which does not handle the "unset" parameter should only be used with
PARSE_OPT_NONEG. But since the callback and the option struct are not
defined next to each other, it's easy to get this wrong (as earlier
patches in this series show).
Fortunately, the compiler can help us here: compiling with
-Wunused-parameters can show us which callbacks ignore their "unset"
parameters (and likewise, ones that ignore "arg" expect to be triggered
with PARSE_OPT_NOARG).
But after we've inspected a callback and determined that all of its
callers use the right flags, what do we do next? We'd like to silence
the compiler warning, but do so in a way that will catch any wrong calls
in the future.
We can do that by actually checking those variables and asserting that
they match our expectations. Because this is such a common pattern,
we'll introduce some helper macros. The resulting messages aren't
as descriptive as we could make them, but the file/line information from
BUG() is enough to identify the problem (and anyway, the point is that
these should never be seen).
Each of the annotated callbacks in this patch triggers
-Wunused-parameters, and was manually inspected to make sure all callers
use the correct options (so none of these BUGs should be triggerable).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are no users of OPT_DATE except for test-parse-options; its
only caller went away in 27ec394a97 (prune: introduce OPT_EXPIRY_DATE()
and use it, 2013-04-25).
It also has a bug: it does not specify PARSE_OPT_NONEG, but its callback
does not respect the "unset" flag, and will feed NULL to approxidate()
and segfault. Probably this should be marked with NONEG, or the callback
should set the timestamp to some sentinel value (e.g,. "0", or
"(time_t)-1").
But since there are no callers, deleting it means we don't even have to
think about what the right behavior should be.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The option callback for "apply --whitespace" exits with status "1" on
error. It makes more sense for it to just return an error to
parse-options. That code will exit, too, but it will use status "129"
that is customary for option errors.
The exit() dates back to aaf6c447aa (builtin/apply: make
parse_whitespace_option() return -1 instead of die()ing, 2016-08-08).
That commit gives no reason why we'd prefer the current exit status (it
looks like it was just bumping the "die" up a level in the callstack,
but did not go as far as it could have).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The options callback for --batch and --batch-check detects when the two
mutually incompatible options are used. But it simply returns an error
code to parse-options, meaning the program will quit without any kind of
message to the user.
Instead, let's use error() to print something and return -1. Note that
this flips the error return from 1 to -1, but negative values are more
idiomatic here (and parse-options treats them the same).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We do not allow "--no-message" to work now, as the option callback
returns "-1" when it sees a NULL arg. However, that will cause
parse-options to exit(129) without printing anything further, leaving
the user confused about what happened.
Instead, let's explicitly mark it as PARSE_OPT_NONEG, which will give a
useful error message (and print the usual -h output).
In theory this could be used to override an earlier "-m", but it's not
clear how it would interact with other message options (e.g., would it
also clear data read for "-F"?). Since it's already disabled and nobody
is asking for it, let's punt on that and just improve the error message.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Running "git show-branch --no-reflog" will behave as if "--reflog" was
given with no options, which makes no sense.
In theory this option might be used to cancel an earlier "--reflog"
option, but the semantics are not clear. Let's punt on it and just
disallow the broken option.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have separate parse-options entries for "numbered" and "no-numbered",
which means that we accept "--no-no-numbered". It does not behave
sensibly, though (it ignores the "unset" flag and acts like
"--no-numbered").
We could fix that, but obviously this is silly and unintentional. Let's
just disallow it.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If you run "git status --no-find-renames", it will behave the same as
"--find-renames", because we ignore the "unset" parameter (we see a NULL
"arg", but since the score argument is optional, we just think that the
user did not provide a score).
We already have a separate "--no-renames" to disable renames, so there's
not much point in supporting "--no-find-renames". Let's just flag it as
an error.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Running "cat-file --no-batch" will behave as if "--batch" was given,
since the option callback does not handle the "unset" flag (likewise for
"--no-batch-check").
In theory this might be used to cancel an earlier --batch, but it's not
immediately obvious how that would interact with --batch-check. Let's
just disallow the negated form of both options.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Running "git pack-objects --no-index-version" will segfault, since the
callback is not prepared to handle the "unset" flag.
In theory this might be used to counteract an earlier "--index-version",
or override a pack.indexversion config setting. But the semantics aren't
immediately obvious, and it's unlikely anybody wants this. Let's just
disable the broken option for now.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Running "git ls-files --no-exclude" will currently segfault, as its
option callback does not handle the "unset" parameter.
In theory this could be used to clear the exclude list, but it is not
clear how that would interact with the other exclude options, nor is the
current code capable of clearing the list. Let's just disable the broken
option.
Note that --no-exclude-from will similarly segfault, but
--no-exclude-standard will not. It just silently does the wrong thing
(pretending as if --exclude-standard was specified).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Running "git am --no-patch-format" will currently segfault, since it
tries to parse a NULL argument. Instead, let's have it cancel any
previous --patch-format option.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The options callback for "git apply --no-include" is not ready to handle
the "unset" parameter, and as a result will segfault when it adds a NULL
argument to the include list (likewise for "--no-exclude").
In theory this might be used to clear the list, but since both
"--include" and "--exclude" add to the same list, it's not immediately
obvious what the semantics should be. Let's punt on that for now and
just disallow the broken options.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With refresh_index() learning to utilize preload_index() to speed up its
operation there is no longer any benefit to having the caller preload the
index first. Remove those unneeded calls by calling read_index() instead of
the preload variant.
There is no measurable performance impact of this patch - the 2nd call to
preload_index() bails out quickly but there is no reason to call it twice.
Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Normally pthread_create() rarely fails. But with new pthreads wrapper,
pthread_create() will return ENOSYS on a system without thread support.
Threaded code _is_ protected by HAVE_THREADS and pthread_create()
should never run in the first place. But the situation could change in
the future and bugs may sneak in. Make sure that all pthread_create()
reports the error cause.
While at there, mark these strings for translation if they aren't.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It was reported that when building with NO_PTHREADS=1,
-Wmaybe-uninitialized is triggered. Just initialize the variable from
the beginning to shut the compiler up (because this warning is enabled
in config.dev)
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a faithful conversion with no attempt to clean up whatsoever.
Code indentation is left broken. There will be another commit to clean
it up and un-indent if we just indent now. It's just more code noise.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
