The subcommands are used exactly once, at the very beginning of
sequencer_pick_revisions(), to determine what to do. This is an
unnecessary level of indirection: we can simply call the correct
function to begin with. So let's do that.
While at it, ensure that the subcommands return an error code so that
they do not have to die() all over the place (bad practice for library
functions...).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is not unheard of that editors on Windows write CR/LF even if the
file originally had only LF. This is particularly awkward for exec lines
of a rebase -i todo sheet. Take for example the insn "exec echo": The
shell script parser splits at the LF and leaves the CR attached to
"echo", which leads to the unknown command "echo\r".
Work around that by stripping CR when reading the todo commands, as we
already do for LF.
This happens to fix t9903.14 and .15 in MSYS1 environments (with the
rebase--helper patches based on this patch series): the todo script
constructed in such a setup contains CR/LF thanks to MSYS1 runtime's
cleverness.
Based on a report and a patch by Johannes Sixt.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we came up with the "sequencer" idea, we really wanted to have
kind of a plumbing equivalent of the interactive rebase. Hence the
choice of words: the "todo" script, a "pick", etc.
However, when it came time to implement the entire shebang, somehow this
idea got lost and the sequencer was used as working horse for
cherry-pick and revert instead. So as not to interfere with the
interactive rebase, it even uses a separate directory to store its
state.
Furthermore, it also is stupidly strict about the "todo" script it
accepts: while it parses commands in a way that was *designed* to be
similar to the interactive rebase, it then goes on to *error out* if the
commands disagree with the overall action (cherry-pick or revert).
Finally, the sequencer code chose to deviate from the interactive rebase
code insofar that when it comes to writing the file with the remaining
commands, it *reformats* the "todo" script instead of just writing the
part of the parsed script that were not yet processed. This is not only
unnecessary churn, but might well lose information that is valuable to
the user (i.e. comments after the commands).
Let's just bite the bullet and rewrite the entire parser; the code now
becomes not only more elegant: it allows us to go on and teach the
sequencer how to parse *true* "todo" scripts as used by the interactive
rebase itself. In a way, the sequencer is about to grow up to do its
older brother's job. Better.
In particular, we choose to maintain the list of commands in an array
instead of a linked list: this is flexible enough to allow us later on to
even implement rebase -i's reordering of fixup!/squash! commits very
easily (and with a very nice speed bonus, at least on Windows).
While at it, do not stop at the first problem, but list *all* of the
problems. This will help the user when the sequencer will do `rebase
-i`'s work by allowing to address all issues in one go rather than going
back and forth until the todo list is valid.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Not only does this DRY up the code (providing a better documentation what
the code is about, as well as allowing to change the behavior in a single
place), it also makes it substantially shorter to use the same
functionality in functions to be introduced when we teach the sequencer to
process interactive-rebase's git-rebase-todo file.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Over the next commits, we will work on improving the sequencer to the
point where it can process the todo script of an interactive rebase. To
that end, we will need to teach the sequencer to read interactive
rebase's todo file. In preparation, we consolidate all places where
that todo file is needed to call a function that we will later extend.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The sequencer is our attempt to lib-ify cherry-pick. Yet it behaves
like a one-shot command when it reads its configuration: memory is
allocated and released only when the command exits.
This is kind of okay for git-cherry-pick, which *is* a one-shot
command. All the work to make the sequencer its work horse was
done to allow using the functionality as a library function, though,
including proper clean-up after use.
To remedy that, take custody of the option values in question,
allocating and duping literal constants as needed and freeing them
at end.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a couple of commits, we will teach the sequencer to handle the
nitty gritty of the interactive rebase, which keeps its state in a
different directory.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We really do not need the *pointer to a* pointer to the options in
the read_populate_opts() function.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A future caller of read_and_refresh_cache() may want to do more than just
print some helpful advice in case of failure.
Suggested by Junio Hamano.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain
notice the error and handle it (by dying, still).
The only caller of fast_forward_to(), do_pick_commit() already checks
the return value and passes it on to its callers, so its caller must
be already prepared to handle error returns, and with this step, we
make it notice an error return from this function.
So this is a safe conversion to make fast_forward_to() callable from
new callers that want it not to die, without changing the external
behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The only caller of save_opts(), sequencer_pick_revisions() can already
return errors, so its caller must be already prepared to handle error
returns, and with this step, we make it notice an error return from
this function.
So this is a safe conversion to make save_opts() callable from new
callers that want it not to die, without changing the external
behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The only caller of save_todo(), pick_commits() can already return
errors, so its caller must be already prepared to handle error
returns, and with this step, we make it notice an error return from
this function.
So this is a safe conversion to make save_todo() callable
from new callers that want it not to die, without changing the
external behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The only caller of save_head(), sequencer_pick_revisions() can already
return errors, so its caller must be already prepared to handle error
returns, and with this step, we make it notice an error return from
this function.
So this is a safe conversion to make save_head() callable from new
callers that want it not to die, without changing the external
behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The only caller of create_seq_dir(), sequencer_pick_revisions() can
already return errors, so its caller must be already prepared to
handle error returns, and with this step, we make it notice an error
return from this function.
So this is a safe conversion to make create_seq_dir() callable from
new callers that want it not to die, without changing the external
behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The only caller of read_populate_opts(), sequencer_continue() can
already return errors, so its caller must be already prepared to
handle error returns, and with this step, we make it notice an error
return from this function.
So this is a safe conversion to make read_populate_opts() callable
from new callers that want it not to die, without changing the
external behaviour of anything existing.
Note that the function git_config_from_file(), called from
read_populate_opts(), can currently still die() (in git_parse_source(),
because the do_config_from_file() function sets die_on_error = 1). We do
not try to fix that here, as it would have larger ramifications on the
config code, and we also assume that we write the opts file
programmatically, hence any parse errors would be bugs.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain
notice the error and handle it (by dying, still).
The only caller of read_populate_todo(), sequencer_continue() can
already return errors, so its caller must be already prepared to
handle error returns, and with this step, we make it notice an
error return from this function.
So this is a safe conversion to make read_populate_todo() callable
from new callers that want it not to die, without changing the
external behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain
notice the error and handle it (by dying, still).
There are two call sites of read_and_refresh_cache(), one of which is
pick_commits(), whose callers were already prepared to do the right
thing given an "error" return from it by an earlier patch, so the
conversion is safe.
The other one, sequencer_pick_revisions() was also prepared to relay
an error return back to its caller in all remaining cases in an
earlier patch.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The only caller of prepare_revs(), walk_revs_populate_todo() was just
taught to return errors, after verifying that its callers are prepared
to handle error returns, and with this step, we make it notice an
error return from this function.
So this is a safe conversion to make prepare_revs() callable from new
callers that want it not to die, without changing the external
behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The function sequencer_pick_revisions() is the only caller of
walk_revs_populate_todo(), and it already returns errors
appropriately, so its caller must be already prepared to handle error
returns, and with this step, we make it notice an error return from
this function.
So this is a safe conversion to make walk_revs_populate_todo()
callable from new callers that want it not to die, without changing
the external behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The only two callers of do_pick_commit(), pick_commits() and
single_pick() already check the return value and pass it on to their
callers, so their callers must be already prepared to handle error
returns, and with this step, we make it notice an error return from
this function.
So this is a safe conversion to make do_pick_commit() callable from
new callers that want it not to die, without changing the external
behaviour of anything existing.
While at it, remove the superfluous space.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain
notice the error and handle it (by dying, still).
The only caller of do_recursive_merge(), do_pick_commit() already
checks the return value and passes it on to its callers, so its caller
must be already prepared to handle error returns, and with this step,
we make it notice an error return from this function.
So this is a safe conversion to make do_recursive_merge() callable
from new callers that want it not to die, without changing the
external behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain
notice the error and handle it (by dying, still).
The only caller of write_message(), do_pick_commit() already checks
the return value and passes it on to its callers, so its caller must
be already prepared to handle error returns, and with this step, we
make it notice an error return from this function.
So this is a safe conversion to make write_message() callable
from new callers that want it not to die, without changing the
external behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain
notice the error and handle it (by dying, still).
The eventual caller of do_pick_commit() is sequencer_pick_revisions(),
which already relays a reported error from its helper functions
(including this one), and both of its two callers know how to react to
a negative return correctly.
So this makes do_pick_commit() callable from new callers that want it
not to die, without changing the external behaviour of anything
existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying there, let the caller high up in the callchain notice
the error and handle it (by dying, still).
The function sequencer_pick_revisions() has only two callers,
cmd_revert() and cmd_cherry_pick(), both of which check the return
value and react appropriately upon errors.
So this is a safe conversion to make sequencer_pick_revisions()
callable from new callers that want it not to die, without changing
the external behaviour of anything existing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git am -3" calls "git merge-recursive" when it needs to fall back
to a three-way merge; this call has been turned into an internal
subroutine call instead of spawning a separate subprocess.
* js/am-3-merge-recursive-direct:
merge-recursive: flush output buffer even when erroring out
merge_trees(): ensure that the callers release output buffer
merge-recursive: offer an option to retain the output in 'obuf'
merge-recursive: write the commit title in one go
merge-recursive: flush output buffer before printing error messages
am -3: use merge_recursive() directly again
merge-recursive: switch to returning errors instead of dying
merge-recursive: handle return values indicating errors
merge-recursive: allow write_tree_from_memory() to error out
merge-recursive: avoid returning a wholesale struct
merge_recursive: abort properly upon errors
prepare the builtins for a libified merge_recursive()
merge-recursive: clarify code in was_tracked()
die(_("BUG")): avoid translating bug messages
die("bug"): report bugs consistently
t5520: verify that `pull --rebase` shows the helpful advice when failing
Call strbuf_addstr() for adding a simple string to a strbuf instead of
using the heavier strbuf_addf(). This is shorter and documents the
intent more clearly.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The recursive merge machinery accumulates its output in an output
buffer, to be flushed at the end of merge_recursive(). At this point,
we forgot to release the output buffer.
When calling merge_trees() (i.e. the non-recursive part of the recursive
merge) directly, the output buffer is never flushed because the caller
may be merge_recursive() which wants to flush the output itself.
For the same reason, merge_trees() cannot release the output buffer: it
may still be needed.
Forgetting to release the output buffer did not matter much when running
git-checkout, or git-merge-recursive, because we exited after the
operation anyway. Ever since cherry-pick learned to pick a commit range,
however, this memory leak had the potential of becoming a problem.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A helper function that takes the contents of a commit object and
finds its subject line did not ignore leading blank lines, as is
commonly done by other codepaths. Make it ignore leading blank
lines to match.
* js/find-commit-subject-ignore-leading-blanks:
reset --hard: skip blank lines when reporting the commit subject
sequencer: use skip_blank_lines() to find the commit subject
commit -C: skip blank lines at the beginning of the message
commit.c: make find_commit_subject() more robust
pretty: make the skip_blank_lines() function public
Previously, callers of merge_trees() or merge_recursive() expected that
code to die() with an error message. This used to be okay because we
called those commands from scripts, and had a chance to print out a
message in case the command failed fatally (read: with exit code 128).
As scripting incurs its own set of problems (portability, speed,
idiosyncrasies of different shells, limited data structures leading to
inefficient code), we are converting more and more of these scripts into
builtins, using library functions directly.
We already tried to use merge_recursive() directly in the builtin
git-am, for example. Unfortunately, we had to roll it back temporarily
because some of the code in merge-recursive.c still deemed it okay to
call die(), when the builtin am code really wanted to print out a useful
advice after the merge failed fatally. In the next commits, we want to
fix that.
The code touched by this commit expected merge_trees() to die() with
some useful message when there is an error condition, but merge_trees()
is going to be improved by converting all die() calls to return error()
instead (i.e. return value -1 after printing out the message as before),
so that the caller can react more flexibly.
This is a step to prepare for the version of merge_trees() that no
longer dies, even if we just imitate the previous behavior by calling
exit(128): this is what callers of e.g. `git merge` have come to expect.
Note that the callers of the sequencer (revert and cherry-pick) already
fail fast even for the return value -1; The only difference is that they
now get a chance to say "<command> failed".
A caller of merge_trees() might want handle error messages themselves
(or even suppress them). As this patch is already complex enough, we
leave that change for a later patch.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More markings of messages for i18n, with updates to various tests
to pass GETTEXT_POISON tests.
One patch from the original submission dropped due to conflicts
with jk/upload-pack-hook, which is still in flux.
* va/i18n-even-more: (38 commits)
t5541: become resilient to GETTEXT_POISON
i18n: branch: mark comment when editing branch description for translation
i18n: unmark die messages for translation
i18n: submodule: escape shell variables inside eval_gettext
i18n: submodule: join strings marked for translation
i18n: init-db: join message pieces
i18n: remote: allow translations to reorder message
i18n: remote: mark URL fallback text for translation
i18n: standardise messages
i18n: sequencer: add period to error message
i18n: merge: change command option help to lowercase
i18n: merge: mark messages for translation
i18n: notes: mark options for translation
i18n: notes: mark strings for translation
i18n: transport-helper.c: change N_() call to _()
i18n: bisect: mark strings for translation
t5523: use test_i18ngrep for negation
t4153: fix negated test_i18ngrep call
t9003: become resilient to GETTEXT_POISON
tests: unpack-trees: update to use test_i18n* functions
...
A helper function that takes the contents of a commit object and
finds its subject line did not ignore leading blank lines, as is
commonly done by other codepaths. Make it ignore leading blank
lines to match.
* js/find-commit-subject-ignore-leading-blanks:
reset --hard: skip blank lines when reporting the commit subject
sequencer: use skip_blank_lines() to find the commit subject
commit -C: skip blank lines at the beginning of the message
commit.c: make find_commit_subject() more robust
pretty: make the skip_blank_lines() function public
"git cherry-pick A" worked on an unborn branch, but "git
cherry-pick A..B" didn't.
* mg/cherry-pick-multi-on-unborn:
cherry-pick: allow to pick to unborn branches
Just like we already taught the find_commit_subject() function (to make
it consistent with the code in pretty.c), we now simply skip leading
blank lines of the commit message.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git cherry-pick A" worked on an unborn branch, but "git
cherry-pick A..B" didn't.
* mg/cherry-pick-multi-on-unborn:
cherry-pick: allow to pick to unborn branches
Add a period to error message so it matches others instances in
sequencer.c. Now translator would have to translate such message only
once.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Mark informative string "<action_name>: fast-forward" for translation.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Mark entire sentences of error message rather than assembling one using
placeholders (e.g. "Cannot %s during a %s").
That would facilitate translation work because it is easier to translate
a entire sentence than translating pieces. We would have better
translations at the expense of source code verbosity.
Moreover, translators can now 1) translate the terms "revert" and
"cherry-pick" if they please 2) have more leeway to adapt their
translations.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
cherry-pick allows to pick single commits to an empty HEAD, but not
multiple commits.
Allow the multiple commit case, too.
Reported-by: Fabrizio Cucci <fabrizio.cucci@gmail.com>
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update various codepaths to avoid manually-counted malloc().
* jk/tighten-alloc: (22 commits)
ewah: convert to REALLOC_ARRAY, etc
convert ewah/bitmap code to use xmalloc
diff_populate_gitlink: use a strbuf
transport_anonymize_url: use xstrfmt
git-compat-util: drop mempcpy compat code
sequencer: simplify memory allocation of get_message
test-path-utils: fix normalize_path_copy output buffer size
fetch-pack: simplify add_sought_entry
fast-import: simplify allocation in start_packfile
write_untracked_extension: use FLEX_ALLOC helper
prepare_{git,shell}_cmd: use argv_array
use st_add and st_mult for allocation size computation
convert trivial cases to FLEX_ARRAY macros
use xmallocz to avoid size arithmetic
convert trivial cases to ALLOC_ARRAY
convert manual allocations to argv_array
argv-array: add detach function
add helpers for allocating flex-array structs
harden REALLOC_ARRAY and xcalloc against size_t overflow
tree-diff: catch integer overflow in combine_diff_path allocation
...
For a commit with sha1 "1234abcd" and subject "foo", this
function produces a struct with three strings:
1. "foo"
2. "1234abcd... foo"
3. "parent of 1234abcd... foo"
It takes advantage of the fact that these strings are
subsets of each other, and allocates only _one_ string, with
pointers into the various parts. Unfortunately, this makes
the string allocation complicated and hard to follow.
Since we keep only one of these in memory at a time, we can
afford to simply allocate three strings. This lets us build
on tools like xstrfmt and avoid manual computation.
While we're here, we can also drop the ad-hoc
reimplementation of get_git_commit_encoding(), and simply
call that function.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The strbuf_getline() interface allows a byte other than LF or NUL as
the line terminator, but this is only because I wrote these
codepaths anticipating that there might be a value other than NUL
and LF that could be useful when I introduced line_termination long
time ago. No useful caller that uses other value has emerged.
By now, it is clear that the interface is overly broad without a
good reason. Many codepaths have hardcoded preference to read
either LF terminated or NUL terminated records from their input, and
then call strbuf_getline() with LF or NUL as the third parameter.
This step introduces two thin wrappers around strbuf_getline(),
namely, strbuf_getline_lf() and strbuf_getline_nul(), and
mechanically rewrites these call sites to call either one of
them. The changes contained in this patch are:
* introduction of these two functions in strbuf.[ch]
* mechanical conversion of all callers to strbuf_getline() with
either '\n' or '\0' as the third parameter to instead call the
respective thin wrapper.
After this step, output from "git grep 'strbuf_getline('" would
become a lot smaller. An interim goal of this series is to make
this an empty set, so that we can have strbuf_getline_crlf() take
over the shorter name strbuf_getline().
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert all instances of get_object_hash to use an appropriate reference
to the hash member of the oid member of struct object. This provides no
functional change, as it is essentially a macro substitution.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
struct object is one of the major data structures dealing with object
IDs. Convert it to use struct object_id instead of an unsigned char
array. Convert get_object_hash to refer to the new member as well.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
Convert most instances where the sha1 member of struct object is
dereferenced to use get_object_hash. Most instances that are passed to
functions that have versions taking struct object_id, such as
get_sha1_hex/get_oid_hex, or instances that can be trivially converted
to use struct object_id instead, are not converted.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
To prepare for allowing a different "ref" backend to be plugged in
to the system, update_ref()/delete_ref() have been taught about
ref-like things like MERGE_HEAD that are per-worktree (they will
always be written to the filesystem inside $GIT_DIR).
* dt/refs-pseudo:
pseudoref: check return values from read_ref()
sequencer: replace write_cherry_pick_head with update_ref
bisect: use update_ref
pseudorefs: create and use pseudoref update and delete functions
refs: add ref_type function
refs: introduce pseudoref and per-worktree ref concepts