The option_parse_strategy() callback does not look at opt->value;
instead it calls append_strategy(), which manipulates the global
use_strategies array directly. But the OPT_CALLBACK declaration assigns
"&use_strategies" to opt->value.
One could argue this is good, as it tells the reader what we generally
expect the callback to do. But it is also bad, because it can mislead
you into thinking that swapping out "&use_strategies" there might have
any effect. Let's switch it to pass NULL (which is what every other
"does not bother to look at opt->value" callback does). If you want to
know what the callback does, it's easy to read the function itself.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous commit argued that parse-options callbacks should try to
use opt->value rather than touching globals directly. In some cases,
however, that's awkward to do. Some callbacks touch multiple variables,
or may even just call into an abstracted function that does so.
In some of these cases we _could_ convert them by stuffing the multiple
variables into a single struct and passing the struct pointer through
opt->value. But that may make other parts of the code less readable,
as the struct relationship has to be mentioned everywhere.
Let's just accept that these cases are special and leave them as-is. But
we do need to mark their "opt" parameters to satisfy -Wunused-parameter.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have several parse-options callbacks that ignore their "opt"
parameters entirely. This is a little unusual, as we'd normally put the
result of the parsing into opt->value. In the case of these callbacks,
though, they directly manipulate global variables instead (and in
most cases the caller sets opt->value to NULL in the OPT_CALLBACK
declaration).
The immediate symptom we'd like to deal with is that the unused "opt"
variables trigger -Wunused-parameter. But how to fix that is debatable.
One option is to annotate them with UNUSED. But another is to have the
caller pass in the appropriate variable via opt->value, and use it. That
has the benefit of making the callbacks reusable (in theory at least),
and makes it clear from the OPT_CALLBACK declaration which variables
will be affected (doubly so for the cases in builtin/fast-export.c,
where we do set opt->value, but it is completely ignored!).
The slight downside is that we lose type safety, since they're now
passing through void pointers.
I went with the "just use them" approach here. The loss of type safety
is unfortunate, but that is already an issue with most of the other
callbacks. If we want to try to address that, we should do so more
consistently (and this patch would prepare these callbacks for whatever
we choose to do there).
Note that in the cases in builtin/fast-export.c, we are passing
anonymous enums. We'll have to give them names so that we can declare
the appropriate pointer type within the callbacks.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using --stage=all requires writing to tempfiles, since we cannot put
multiple stages into a single file. So --stage=all implies --temp.
But we do so by setting to_tempfile in the options callback for --stage,
rather than after all options have been parsed. This leads to two bugs:
1. If you run "checkout-index --stage=all --stage=2", this should not
imply --temp, but it currently does. The callback cannot just unset
to_tempfile when it sees the "2" value, because it no longer knows
if its value was from the earlier --stage call, or if the user
specified --temp explicitly.
2. If you run "checkout-index --stage=all --no-temp", the --no-temp
will overwrite the earlier implied --temp. But this mode of
operation cannot work, and the command will fail with "<path>
already exists" when trying to write the higher stages.
We can fix both by lazily setting to_tempfile. We'll make it a tristate,
with -1 as "not yet given", and have --stage=all enable it only after
all options are parsed. Likewise, after all options are parsed we can
detect and reject the bogus "--no-temp" case.
Note that this does technically change the behavior for "--stage=all
--no-temp" for paths which have only one stage present (which
accidentally worked before, but is now forbidden). But this behavior was
never intended, and you'd have to go out of your way to try to trigger
it.
The new tests cover both cases, as well the general "--stage=all implies
--temp", as most of the other tests explicitly say "--temp". Ironically,
the test "checkout --temp within subdir" is the only one that _doesn't_
use "--temp", and so was implicitly covering this case. But it seems
reasonable to have a more explicit test alongside the other related
ones.
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The to_callback() and cc_callback() functions are identical to the
generic parse_opt_string_list() function (except that they don't handle
optional arguments, but that's OK because their callers do not use the
OPTARG flag).
Let's simplify the code by using OPT_STRING_LIST.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "-n" option is implemented by an option callback, as it is really a
"reverse bool". If given, it sets show_diffstat to 0. In theory, when
negated, it would set the same flag to 1. But it's not possible to
trigger that, since short options cannot be negated.
So in practice this is really just a SET_INT to 0. Let's use that
instead, which shortens the code.
Note that negation here would do the wrong thing (as with any SET_INT
with a value of "0"). We could specify PARSE_OPT_NONEG to future-proof
ourselves against somebody adding a long option name (which would make
it possible to negate). But there's not much point:
1. Nobody is going to do that, because the negated form already
exists, and is called "--stat" (which is defined separately so that
"--no-stat" works).
2. If they did, the BUG() check added by 3284b93862 (parse-options:
disallow negating OPTION_SET_INT 0, 2023-08-08) will catch it (and
that check is smart enough to realize that our short-only option is
OK).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "xopts" variable uses a custom array with ALLOC_GROW(). Using a
strvec simplifies things a bit. We need fewer variables, and we can also
ditch our custom parseopt callback in favor of OPT_STRVEC().
As a bonus, this means that "--no-strategy-option", which was previously
a silent noop, now does something useful: like other list-like options,
it will clear the list of -X options seen so far. This matches the
behavior of revert/cherry-pick, which made the same change in fb60b9f37f
(sequencer: use struct strvec to store merge strategy options,
2023-04-10).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
transfer.unpackLimit ought to be used as a fallback, but overrode
fetch.unpackLimit and receive.unpackLimit instead.
* ts/unpacklimit-config-fix:
transfer.unpackLimit: fetch/receive.unpackLimit takes precedence
"git diff -w --exit-code" with various options did not work
correctly, which is being addressed.
* jc/diff-exit-code-with-w-fixes:
diff: the -w option breaks --exit-code for --raw and other output modes
t4040: remove test that succeeded for a wrong reason
diff: teach "--stat -w --exit-code" to notice differences
diff: mode-only change should be noticed by "--patch -w --exit-code"
diff: move the fallback "--exit-code" code down
The commit-graph verification code that detects mixture of zero and
non-zero generation numbers has been updated.
* tb/commit-graph-verify-fix:
commit-graph: avoid repeated mixed generation number warnings
t/t5318-commit-graph.sh: test generation zero transitions during fsck
commit-graph: verify swapped zero/non-zero generation cases
commit-graph: introduce `commit_graph_generation_from_graph()`
Git GUI updates.
* py/git-gui-updates:
git-gui - use mkshortcut on Cygwin
git-gui - use cygstart to browse on Cygwin
git-gui - remove obsolete Cygwin specific code
git gui Makefile - remove Cygwin modifications
Makefiles: change search through $(MAKEFLAGS) for GNU make 4.4
Work around Tcl's default `PATH` lookup
Move the `_which` function (almost) to the top
Move is_<platform> functions to the beginning
is_Cygwin: avoid `exec`ing anything
windows: ignore empty `PATH` elements
git-gui: Fix a typo in README
Tweak GitHub Actions CI so that pushing the same commit to multiple
branch tips at the same time will not waste building and testing
the same thing twice.
* jc/ci-skip-same-commit:
ci: avoid building from the same commit in parallel
Teach "git check-attr" work better with sparse-index.
* sl/sparse-check-attr:
check-attr: integrate with sparse-index
attr.c: read attributes in a sparse directory
t1092: add tests for 'git check-attr'
These two topics did not see much interest and reviews while they
were on 'next'; let's "inflict" them to the general public and see
if anybody screams, which is much less nicer way than to merge
only topics that are well reviewed down in an orderly manner, but
that is the only thing we can do to these topics without any
development community help.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update two credential helpers to correctly match which credential
to erase; they dropped not the ones with stale password.
* mh/credential-erase-improvements-more:
credential/wincred: erase matching creds only
credential/libsecret: erase matching creds only
The way authentication related data other than passwords (e.g.
oath token and password expiration data) are stored in libsecret
keyrings has been rethought.
* mh/credential-libsecret-attrs:
credential/libsecret: store new attributes
When running 'scalar reconfigure -a', Scalar has warning messages about
the repository missing (or not containing a .git directory). Failures
can also happen while trying to modify the repository-local config for
that repository.
These warnings may seem confusing to users who don't understand what
they mean or how to stop them.
Add a warning that instructs the user how to remove the warning in
future installations.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are many reasons why discovering a Git directory may fail. In
particular, 8959555cee (setup_git_directory(): add an owner check for
the top-level directory, 2022-03-02) added ownership checks as a
security precaution.
Callers attempting to set up a Git directory may want to inform the user
about the reason for the failure. For that, expose the enum
discovery_result from within setup.c and move it into cache.h where
discover_git_directory() is defined.
I initially wanted to change the return type of discover_git_directory()
to be this enum, but several callers rely upon the "zero means success".
The two problems with this are:
1. The zero value of the enum is actually GIT_DIR_NONE, so nonpositive
results are errors.
2. There are multiple successful states; positive results are
successful.
It is worth noting that GIT_DIR_NONE is not returned, so we remove this
option from the enum. We must be careful to keep the successful reasons
as positive values, so they are given explicit positive values.
Instead of updating all callers immediately, add a new method,
discover_git_directory_reason(), and convert discover_git_directory() to
be a thin shim on top of it.
One thing that is important to note is that discover_git_directory()
previously returned -1 on error, so let's continue that into the future.
There is only one caller (in scalar.c) that depends on that signedness
instead of a non-zero check, so clean that up, too.
Because there are extra checks that discover_git_directory_reason() does
after setup_git_directory_gently_1(), there are other modes that can be
returned for failure states. Add these modes to the enum, but be sure to
explicitly add them as BUG() states in the switch of
setup_git_directory_gently().
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some users have strong aversions to Scalar's opinion that the repository
should be in a 'src' directory, even though this creates a clean slate
for placing build artifacts in adjacent directories.
The new --no-src option allows users to opt out of the default behavior.
While adding options, make sure the usage output by 'scalar clone -h'
reports the same as the SYNOPSIS line in Documentation/scalar.txt.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git cmd -h" learned to signal which options can be negated by
listing such options like "--[no-]opt".
* rs/parse-options-negation-help:
parse-options: simplify usage_padding()
parse-options: no --[no-]no-...
parse-options: factor out usage_indent() and usage_padding()
parse-options: show negatability of options in short help
t1502: test option negation
t1502: move optionspec help output to a file
t1502, docs: disallow --no-help
subtree: disallow --no-{help,quiet,debug,branch,message}
At times, we may need to push the same commit to multiple branches
in the same push. Rewinding 'next' to rebuild on top of 'master'
soon after a release is such an occasion. Making sure 'main' stays
in sync with 'master' to help those who expect that primary branch
of the project is named either of these is another.
We already use the branch name as a "concurrency group" key, but
that does not address the situation illustrated above.
Let's introduce another `concurrency` attribute, using the commit
hash as the concurrency group key, on the workflow run level, to
address this. This will hold any workflow run in the queued state
when there is already a workflow run targeting the same commit,
until that latter run completed. The `skip-if-redundant` check of
the second run will then have a chance to see whether the first
run succeeded.
The only caveat with this strategy is that only one workflow run
will be kept in the queued state by the `concurrency` feature: if
another run targeting the same commit is triggered, the
previously-queued run will be canceled. Considering the benefit,
this seems the smaller price to pay than to overload Git's build
agent pool with undesired workflow runs.
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* https://github.com/prati0100/git-gui:
git-gui - use mkshortcut on Cygwin
git-gui - use cygstart to browse on Cygwin
git-gui - remove obsolete Cygwin specific code
git gui Makefile - remove Cygwin modifications
Makefiles: change search through $(MAKEFLAGS) for GNU make 4.4
Work around Tcl's default `PATH` lookup
Move the `_which` function (almost) to the top
Move is_<platform> functions to the beginning
is_Cygwin: avoid `exec`ing anything
windows: ignore empty `PATH` elements
git-gui: Fix a typo in README
Hourly and other schedule of "git maintenance" jobs are randomly
distributed now.
* ds/maintenance-schedule-fuzz:
maintenance: update schedule before config
maintenance: fix systemd schedule overlaps
maintenance: use random minute in systemd scheduler
maintenance: swap method locations
maintenance: use random minute in cron scheduler
maintenance: use random minute in Windows scheduler
maintenance: use random minute in launchctl scheduler
maintenance: add get_random_minute()
Test updates.
* ob/test-lib-rebase-fake-editor-updates:
t/lib-rebase: improve documentation of set_fake_editor()
t/lib-rebase: set_fake_editor(): handle FAKE_LINES more consistently
t/lib-rebase: set_fake_editor(): fix recognition of reset's short command
Overly long label names used in the sequencer machinery are now
chopped to fit under filesystem limitation.
* mp/rebase-label-length-limit:
rebase: allow overriding the maximal length of the generated labels
sequencer: truncate labels to accommodate loose refs
A message written in olden time prevented a branch from getting
checked out saying it is already checked out elsewhere, but these
days, we treat a branch that is being bisected or rebased just like
a branch that is checked out and protect it. Rephrase the message
to say that the branch is in use.
* rj/branch-in-use-error-message:
branch: error message checking out a branch in use
branch: error message deleting a branch in use
Remove some code supporting ancient Cygwin Tcl/Tk versions. Also fix
exploring working directory and making desktop shortcuts on Cygwin.
* ml/cygwin-fixes:
git-gui - use mkshortcut on Cygwin
git-gui - use cygstart to browse on Cygwin
git-gui - remove obsolete Cygwin specific code
git gui Makefile - remove Cygwin modifications
git-gui enables the "Repository->Create Desktop Icon" item on Cygwin,
offering to create a shortcut that starts git-gui on the current
repository. The code in do_cygwin_shortcut invokes function
win32_create_lnk to create the shortcut. This latter function is shared
between Cygwin and Git For Windows and expects Windows rather than unix
pathnames, though do_cygwin_shortcut provides unix pathnames. Also, this
function tries to invoke the Windows Script Host to run a javascript
snippet, but this fails under Cygwin's Tcl. So, win32_create_lnk just
does not support Cygwin.
However, Cygwin's default installation provides /bin/mkshortcut for
creating desktop shortcuts. This is compatible with exec under Cygwin's
Tcl, understands Cygwin's unix pathnames, and avoids the need for shell
escapes to encode troublesome paths. So, teach git-gui to use mkshortcut
on Cygwin, leaving win32_create_lnk unchanged and for exclusive use by
Git For Windows.
Notes: "CHERE_INVOKING=1" is recognized by Cygwin's /etc/profile and
prevents a "chdir $HOME", leaving the shell in the working directory
specified by the shortcut. That directory is written directly by
mkshortcut eliminating any problems with shell escapes and quoting.
The code being replaced includes the full pathname of the git-gui
creating the shortcut, but that git-gui might not be compatible with the
git found after /etc/profile sets the path, and might have a pathname
that defies encoding using shell escapes that can survive the multiple
incompatible interpreters involved in the chain of creating and using
this shortcut. The new code uses bare "git gui" as the command to
execute, thus using the system git to launch the system git-gui, and
avoiding both issues.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Pratyush Yadav <me@yadavpratyush.com>
git-gui enables the "Repository->Explore Working Copy" menu on Cygwin,
offering to open a Windows graphical file browser at the root of the
working directory. This code, shared with Git For Windows support,
depends upon use of Windows pathnames. However, git gui on Cygwin uses
unix pathnames, so this shared code will not work on Cygwin.
A base install of Cygwin provides the /bin/cygstart utility that runs
a registered Windows application based upon the file type, after
translating unix pathnames to Windows. Adding the --explore option
guarantees that the Windows file explorer is opened, regardless of the
supplied pathname's file type and avoiding possibility of some other
action being taken.
So, teach git-gui to use cygstart --explore on Cygwin, restoring the
pre-2012 behavior of opening a Windows file explorer for browsing. This
separates the Git For Windows and Cygwin code paths. Note that
is_Windows is never true on Cygwin, and is_Cygwin is never true on Git
for Windows, though this is not obvious by examining the code for those
independent functions.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Pratyush Yadav <me@yadavpratyush.com>
In the current git release, git-gui runs on Cygwin without enabling any
of git-gui's Cygwin specific code. This happens as the Cygwin specific
code in git-gui was (mostly) written in 2007-2008 to work with Cygwin's
then supplied Tcl/Tk which was an incompletely ported variant of the
8.4.1 Windows Tcl/Tk code. In March, 2012, that 8.4.1 package was
replaced with a full port based upon the upstream unix/X11 code,
since maintained up to date. The two Tcl/Tk packages are completely
incompatible, and have different signatures.
When Cygwin's Tcl/Tk signature changed in 2012, git-gui no longer
detected Cygwin, so did not enable Cygwin specific code, and the POSIX
environment provided by Cygwin since 2012 supported git-gui as a generic
unix. Thus, no-one apparently noticed the existence of incompatible
Cygwin specific code.
However, since commit c5766eae6f in the git-gui source tree
(https://github.com/prati0100/git-gui, master at a5005ded), and not yet
pulled into the git repository, the is_Cygwin function does detect
Cygwin using the unix/X11 Tcl/Tk. The Cygwin specific code is enabled,
causing use of Windows rather than unix pathnames, and enabling
incorrect warnings about environment variables that were relevant only
to the old Tcl/Tk. The end result is that (upstream) git-gui is now
incompatible with Cygwin.
So, delete Cygwin specific code (code protected by "if is_Cygwin") that
is not needed in any form to work with the unix/X11 Tcl/Tk.
Cygwin specific code required to enable file browsing and shortcut
creation is not addressed in this patch, does not currently work, and
invocation of those items may leave git-gui in a confused state.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Pratyush Yadav <me@yadavpratyush.com>
git-gui's Makefile hardcodes the absolute Windows path of git-gui's libraries
into git-gui, destroying the ability to package git-gui on one machine and
distribute to others. The intent is to do this only if a non-Cygwin Tcl/Tk is
installed, but the test for this is wrong with the unix/X11 Tcl/Tk shipped
since 2012. Also, Cygwin does not support a non-Cygwin Tcl/Tk.
The Cygwin git maintainer disables this code, so this code is definitely
not in use in the Cygwin distribution.
The simplest fix is to just delete the Cygwin specific code,
allowing the Makefile to work out of the box on Cygwin. Do so.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Pratyush Yadav <me@yadavpratyush.com>
The transfer.unpackLimit configuration variable is documented to be
used only as a fallback value when the more operation-specific
fetch.unpackLimit and receive.unpackLimit variables are not set, but
the implementation had the precedence reversed. Apparently this was
broken since the transfer.unpackLimit was introduced in e28714c5
(Consolidate {receive,fetch}.unpackLimit, 2007-01-24).
Often when documentation and code have diverged for so long, we
prefer to change the documentation instead, to avoid disrupting
users. But doing so would make these weirdly unlike most other
"specific overrides general" config options. And the fact that the
bug has existed for so long without anyone noticing implies to me
that nobody really tries to mix and match them much.
Signed-off-by: Taylor Santiago <taylorsantiago@google.com>
[jc: rewrote the log message, added tests, covered receive-pack as well]
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The output from "--raw", "--name-status", and "--name-only" modes in
"git diff" does depend on and does not reflect how certain different
contents are considered equal, unlike "--patch" and "--stat" output
modes do, when used with options like "-w" (another way of thinking
about it is that it is not like we recompute the hash of the blob
after removing all whitespaces to show "git diff --raw -w" output).
But the fact that "--raw" and friends ignore "-w" is not a good
excuse for "diff --raw -w --exit-code" to also ignore the request to
report the differences with its exit status. When run without "-w",
"git diff --exit-code --raw" does report with its exit status the
differences as requested, and we should do the same when run with
"-w", too.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When validating that a commit-graph has either all zero, or all non-zero
generation numbers, we emit a warning on both the rising and falling
edge of transitioning between the two.
So if we are unfortunate enough to see a commit-graph which has a
repeating sequence of zero, then non-zero generation numbers, we'll
generate many warnings that contain more or less the same information.
Avoid this by keeping track of a single example for a commit with zero-
and non-zero generation, and emit a single warning at the end of
verification if both are non-NULL.
Co-authored-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The second test called "detect incorrect generation number" asserts that
we correctly warn during an fsck when we see a non-zero generation
number after seeing a zero beforehand.
The other transition (going from non-zero to zero) was previously
untested. Test both directions, and rename the existing test to make
clear which direction it is exercising.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In verify_one_commit_graph(), we have code that complains when a commit
is found with a generation number of zero, and then later with a
non-zero number. It works like this:
1. When we see an entry with generation zero, we set the
generation_zero flag to GENERATION_ZERO_EXISTS.
2. When we later see an entry with a non-zero generation, we complain
if the flag is GENERATION_ZERO_EXISTS.
There's a matching GENERATION_NUMBER_EXISTS value, which in theory would
be used to find the case that we see the entries in the opposite order:
1. When we see an entry with a non-zero generation, we set the
generation_zero flag to GENERATION_NUMBER_EXISTS.
2. When we later see an entry with a zero generation, we complain if
the flag is GENERATION_NUMBER_EXISTS.
But that doesn't work; step 2 is implemented, but there is no step 1. We
never use NUMBER_EXISTS at all, and Coverity rightly complains that step
2 is dead code.
We can fix that by implementing that step 1.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 2ee11f7261 (commit-graph: return generation from memory, 2023-03-20),
the `commit_graph_generation()` function stopped returning zeros when
asked to locate the generation number of a given commit.
This was done at the time to prepare for a later change which set
generation values in memory, meaning that we could no longer rely on
`graph_pos` alone to tell us whether or not to trust the generation
number returned by this function.
In 2ee11f7261, it was noted that this change only impacted very old
commit-graphs, which were written with all commits having generation
number 0. Indeed, zero is not a valid generation number, so we should
never expect to see that value outside of the aforementioned case.
The test fallout in 2ee11f7261 indicated that we were no longer able to
fsck a specific old case of commit-graph corruption, where we see a
non-zero generation number after having seen a generation number of 0
earlier.
Introduce a variant of `commit_graph_generation()` which behaves like
that function did prior to 2ee11f7261, known as
`commit_graph_generation_from_graph()`. Then use this function in the
context of `verify_one_commit_graph()`, where we only want to trust the
values from the graph.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
