This drops our line count considerably, and should make
things more readable by keeping the counting logic separate
from the traversal.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The point of xsize_t is to safely cast an off_t into a size_t
(because we are about to mmap). But in count-objects, we are
summing the sizes in an off_t. Using xsize_t means that
count-objects could fail on a 32-bit system with a 4G
object (not likely, as other parts of git would fail, but
we should at least be correct here).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This saves us from manually traversing the directory
structure ourselves.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we mark all reachable objects for pruning, that
includes blobs mentioned by the index. However, we do not
mark these with the SEEN flag, as we do for objects that we
find by traversing (we also do not add them to the pending
list, but that is because there is nothing further to
traverse with them).
This doesn't cause any problems with prune, because it
checks only that the object exists in the global object
hash, and not its flags. However, let's mark these objects
to be consistent and avoid any later surprises.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Prune has to walk $GIT_DIR/objects/?? in order to find the
set of loose objects to prune. Other parts of the code
(e.g., count-objects) want to do the same. Let's factor it
out into a reusable for_each-style function.
Note that this is not quite a straight code movement. The
original code had strange behavior when it found a file of
the form "[0-9a-f]{2}/.{38}" that did _not_ contain all hex
digits. It executed a "break" from the loop, meaning that we
stopped pruning in that directory (but still pruned other
directories!). This was probably a bug; we do not want to
process the file as an object, but we should keep going
otherwise (and that is how the new code handles it).
We are also a little more careful with loose object
directories which fail to open. The original code silently
ignored any failures, but the new code will complain about
any problems besides ENOENT.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We want to add all reflog entries as tips for finding
reachable objects. The revision machinery can already do
this (to support "rev-list --reflog"); we can reuse that
code.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To find the set of reachable objects, we add a bunch of
possible sources to our rev_info, call prepare_revision_walk,
and then launch into a custom walker that handles each
object top. This is a subset of what traverse_commit_list
does, so we can just reuse that code (it can also handle
more complex cases like UNINTERESTING commits and pathspecs,
but we don't use those features).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we enter prepare_revision_walk, we have zero or more
entries in our "pending" array. We disconnect that array
from the rev_info, and then process each entry:
1. If the entry is a commit and the --source option is in
effect, we keep a pointer to the object name.
2. Otherwise, we re-add the item to the pending list with
a blank name.
We then throw away the old array by freeing the array
itself, but do not touch the "name" field of each entry. For
any items of type (2), we leak the memory associated with
the name. This commit fixes that by calling object_array_clear,
which handles the cleanup for us.
That breaks (1), though, because it depends on the memory
pointed to by the name to last forever. We can solve that by
making a copy of the name. This is slightly less efficient,
but it shouldn't matter in practice, as we do it only for
the tip commits of the traversal.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There's currently no easy way to free the memory associated
with an object_array (and in most cases, we simply leak the
memory in a rev_info's pending array). Let's provide a
helper to make this easier to handle.
We can make use of it in list-objects.c, which does the same
thing by hand (but fails to free the "name" field of each
entry, potentially leaking memory).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is not a lot of code, but it's a logical construct that
should not need to be repeated (and we are about to add a
third repetition).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Otherwise, callers must do so or risk triggering warnings
-Wchar-subscript (and rightfully so; a signed char might
cause us to use a bogus negative index into the
hexval_table).
While we are dropping the now-unnecessary casts from the
caller in urlmatch.c, we can get rid of similar casts in
actually parsing the hex by using the hexval() helper, which
implicitly casts to unsigned (but note that we cannot
implement isxdigit in terms of hexval(), as it also casts
its return value to unsigned).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We check the return value of the callback and stop iterating
if it is non-zero. However, we do not make the non-zero
return value available to the caller, so they have no way of
knowing whether the operation succeeded or not (technically
they can keep their own error flag in the callback data, but
that is unlike our other for_each functions).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Also add a gitignore file for generated files.
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-difftool used to create a command list script containing $( ... )
and explicitly calls "sh -c" with this list.
Instead, allow mergetool --tool-help to take a mode parameter and call
mergetool directly to invoke the show_tool_help function. This mode
parameter is intented for use solely by difftool.
Signed-off-by: Charles Bailey <cbailey32@bloomberg.net>
Helped-by: John Keeping <john@keeping.me.uk>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Charles Bailey <cbailey32@bloomberg.net>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Avoid filenames with multiple dots so that overly-picky tools do
not misinterpret their extension.
Previously, foo/bar.ext in the worktree would result in e.g.
./foo/bar.ext.BASE.1234.ext
This can be improved by having only a single .ext and using
underscore instead of dot so that the extension cannot be
misinterpreted. The resulting path becomes:
./foo/bar_BASE_1234.ext
Suggested-by: Sergio Ferrero <sferrero@ensoftcorp.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Prefer "test" over "[ ]" for conditionals.
Prefer "$()" over backticks for command substitutions.
Avoid control structures on a single line with semicolons.
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
AsciiDoc uses a configuration file to implement macros like linkgit,
while Asciidoctor uses Ruby extensions. Implement a Ruby extension that
implements the linkgit macro for Asciidoctor in the same way that
asciidoc.conf does for AsciiDoc.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Asciidoctor takes slightly different arguments from AsciiDoc in some
cases. It has a different name for the HTML backend and the "docbook"
backend produces DocBook 5, not DocBook 4.5. Also, Asciidoctor does not
accept the -f option. Move these values into variables so that they can
be overridden by users wishing to use Asciidoctor instead of Asciidoc.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When removal of a loose or packed ref fails, bail out instead of
trying to finish the transaction. This way, a single error message
can be printed (instead of multiple messages being concatenated by
mistake) and the operator can try to solve the underlying problem
before there is a chance to muck things up even more.
In particular, when git fails to remove a ref, git goes on to try to
delete the reflog. Exiting early lets us keep the reflog.
When git succeeds in deleting a ref A and fails to remove a ref B, it
goes on to try to delete both reflogs. It would be better to just
remove the reflog for A, but that would be a more invasive change.
Failing early means we keep both reflogs, which puts the operator in a
good position to understand the problem and recover.
A long term goal is to avoid these problems altogether and roll back
the transaction on failure. That kind of transactionality will have
to wait for a later series (the plan for which is to make all
destructive work happen in a single update of the packed-refs file).
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The former caller uses unable_to_lock_message now.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some functions that take a strbuf argument to append an error treat
!err as an indication that the message should be suppressed (e.g.,
ref_update_reject_duplicates). Others write the message to stderr on
!err (e.g., repack_without_refs). Others crash (e.g.,
ref_transaction_update).
Some of these behaviors are for historical reasons and others were
accidents. Luckily no callers pass err == NULL any more. Simplify
by consistently requiring the strbuf argument.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Until v2.1.0-rc0~22^2~11 (refs.c: add an err argument to
repack_without_refs, 2014-06-20), repack_without_refs forgot to
provide an error message when commit_packed_refs fails. Even today,
it only provides a message for callers that pass a non-NULL err
parameter. Internal callers in refs.c pass non-NULL err but
"git remote" does not.
That means that "git remote rm" and "git remote prune" can fail
without printing a message about why. Fix them by passing in a
non-NULL err parameter and printing the returned message.
This is the last caller to a ref handling function passing err ==
NULL. A later patch can drop support for err == NULL, avoiding such
problems in the future.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Print a warning message for any bad ref names we find in the repo and
skip them so callers don't have to deal with parsing them.
It might be useful in the future to have a flag where we would not
skip these refs for those callers that want to and are prepared (for
example by using a --format argument with %0 as a delimiter after the
ref name).
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We currently do not handle badly named refs well:
$ cp .git/refs/heads/master .git/refs/heads/master.....@\*@\\.
$ git branch
fatal: Reference has invalid format: 'refs/heads/master.....@*@\.'
$ git branch -D master.....@\*@\\.
error: branch 'master.....@*@\.' not found.
Users cannot recover from a badly named ref without manually finding
and deleting the loose ref file or appropriate line in packed-refs.
Making that easier will make it easier to tweak the ref naming rules
in the future, for example to forbid shell metacharacters like '`'
and '"', without putting people in a state that is hard to get out of.
So allow "branch --list" to show these refs and allow "branch -d/-D"
and "update-ref -d" to delete them. Other commands (for example to
rename refs) will continue to not handle these refs but can be changed
in later patches.
Details:
In resolving functions, refuse to resolve refs that don't pass the
git-check-ref-format(1) check unless the new RESOLVE_REF_ALLOW_BAD_NAME
flag is passed. Even with RESOLVE_REF_ALLOW_BAD_NAME, refuse to
resolve refs that escape the refs/ directory and do not match the
pattern [A-Z_]* (think "HEAD" and "MERGE_HEAD").
In locking functions, refuse to act on badly named refs unless they
are being deleted and either are in the refs/ directory or match [A-Z_]*.
Just like other invalid refs, flag resolved, badly named refs with the
REF_ISBROKEN flag, treat them as resolving to null_sha1, and skip them
in all iteration functions except for for_each_rawref.
Flag badly named refs (but not symrefs pointing to badly named refs)
with a REF_BAD_NAME flag to make it easier for future callers to
notice and handle them specially. For example, in a later patch
for-each-ref will use this flag to detect refs whose names can confuse
callers parsing for-each-ref output.
In the transaction API, refuse to create or update badly named refs,
but allow deleting them (unless they try to escape refs/ and don't match
[A-Z_]*).
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There's no straightforward way to grep for all tests dealing with
invalid refs. Put them in a single test script so it is easy to see
what functionality has not been exercised with bad ref names yet.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since v1.7.9-rc1~10^2 (write_head_info(): handle "extra refs" locally,
2012-01-06), this trick to keep track of ".have" refs that are only
valid on the wire and not on the filesystem is not needed any more.
Simplify by removing support for the REFNAME_DOT_COMPONENT flag.
This means we'll be slightly stricter with invalid refs found in a
packed-refs file or during clone. read_loose_refs() already checks
for and skips refnames with .components so it is not affected.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When "git branch -d" reads the branch it is about to delete, it used
to avoid passing the RESOLVE_REF_READING ('treat missing ref as
error') flag because a symref pointing to a nonexistent ref would show
up as missing instead of as something that could be deleted. To check
if a ref is actually missing, we then check
- is it a symref?
- if not, did it resolve to null_sha1?
Now we pass RESOLVE_REF_NO_RECURSE and the correct information is
returned for a symref even when it points to a missing ref. Simplify
by relying on RESOLVE_REF_READING.
No functional change intended.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a repository gets in a broken state with too much symref nesting,
it cannot be repaired with "git branch -d":
$ git symbolic-ref refs/heads/nonsense refs/heads/nonsense
$ git branch -d nonsense
error: branch 'nonsense' not found.
Worse, "git update-ref --no-deref -d" doesn't work for such repairs
either:
$ git update-ref -d refs/heads/nonsense
error: unable to resolve reference refs/heads/nonsense: Too many levels of symbolic links
Fix both by teaching resolve_ref_unsafe a new RESOLVE_REF_NO_RECURSE
flag and passing it when appropriate.
Callers can still read the value of a symref (for example to print a
message about it) with that flag set --- resolve_ref_unsafe will
resolve one level of symrefs and stop there.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A proposed patch produced broken HEAD reflog entries when checking out
anything other than a branch. The testsuite still passed, so it took
a few days for the bug to be noticed.
Add tests checking the content of the reflog after detaching and
reattaching HEAD so we don't have to rely on manual testing to catch
such problems in the future.
[jn: using 'log -g --format=%H' instead of parsing --oneline output,
resetting state in each test so they can be safely reordered or
skipped]
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
resolve_ref_unsafe takes a boolean argument for reading (a nonexistent ref
resolves successfully for writing but not for reading). Change this to be
a flags field instead, and pass the new constant RESOLVE_REF_READING when
we want this behaviour.
While at it, swap two of the arguments in the function to put output
arguments at the end. As a nice side effect, this ensures that we can
catch callers that were unaware of the new API so they can be audited.
Give the wrapper functions resolve_refdup and read_ref_full the same
treatment for consistency.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
No external users call write_ref_sha1 any more so let's declare it static.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change s_update_ref to use a ref transaction for the ref update.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In _commit, ENOTDIR can happen in the call to lock_ref_sha1_basic, either
when we lstat the new refname or if the name checking function reports that
the same type of conflict happened. In both cases, it means that we can not
create the new ref due to a name conflict.
Start defining specific return codes for _commit. TRANSACTION_NAME_CONFLICT
refers to a failure to create a ref due to a name conflict with another ref.
TRANSACTION_GENERIC_ERROR is for all other errors.
When "git fetch" is creating refs, name conflicts differ from other errors in
that they are likely to be resolved by running "git remote prune <remote>".
"git fetch" currently inspects errno to decide whether to give that advice.
Once it switches to the transaction API, it can check for
TRANSACTION_NAME_CONFLICT instead.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change is_refname_available to take a list of strings to exclude when
checking for conflicts instead of just one single name. We can already
exclude a single name for the sake of renames. This generalizes that support.
ref_transaction_commit already tracks a set of refs that are being deleted
in an array. This array is then used to exclude refs from being written to
the packed-refs file. At some stage we will want to change this array to a
struct string_list and then we can pass it to is_refname_available via the
call to lock_ref_sha1_basic. That will allow us to perform transactions
that perform multiple renames as long as there are no conflicts within the
starting or ending state.
For example, that would allow a single transaction that contains two
renames that are both individually conflicting:
m -> n/n
n -> m/m
No functional change intended yet.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Skip using the lock_any_ref_for_update wrapper and call lock_ref_sha1_basic
directly from the commit function.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the check for check_refname_format from lock_any_ref_for_update to
lock_ref_sha1_basic. At some later stage we will get rid of
lock_any_ref_for_update completely. This has no visible impact to callers
except for the inability to lock badly named refs, which is not possible
today already for other reasons.(*)
Keep lock_any_ref_for_update as a no-op wrapper. It is the public facing
version of this interface and keeping it as a separate function will make
it easier to experiment with the internal lock_ref_sha1_basic signature.
(*) For example, if lock_ref_sha1_basic checks the refname format and
refuses to lock badly named refs, it will not be possible to delete
such refs because the first step of deletion is to lock the ref. We
currently already fail in that case because these refs are not recognized
to exist:
$ cp .git/refs/heads/master .git/refs/heads/echo...\*\*
$ git branch -D .git/refs/heads/echo...\*\*
error: branch '.git/refs/heads/echo...**' not found.
This has been broken for a while. Later patches in the series will start
repairing the handling of badly named refs.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We call read_ref_full with a pointer to flags from rename_ref but since
we never actually use the returned flags we can just pass NULL here instead.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the ref transaction API so that we pass the reflog message to the
create/delete/update functions instead of to ref_transaction_commit.
This allows different reflog messages for each ref update in a multi-ref
transaction.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add an err argument to delete_ref_loose so that we can pass a descriptive
error string back to the caller. Pass the err argument from transaction
commit to this function so that transaction users will have a nice error
string if the transaction failed due to delete_ref_loose.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This behaves like unlink_or_warn except that on failure it writes the message
to its 'err' argument, which the caller can display in an appropriate way or
ignore.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
lock_ref_sha1_basic is used to lock refs that sit directly in the .git
dir such as HEAD and MERGE_HEAD in addition to the more ordinary refs
under "refs/". Remove the note claiming otherwise.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Simplify the function warn_if_unremovable slightly. Additionally, change
behaviour slightly. If we failed to remove the object because the object
does not exist, we can still return success back to the caller since none of
the callers depend on "fail if the file did not exist".
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The tests for 'git mv moves a submodule' functionality often run
commands like
git mv sub mod/sub
to move a submodule into a subdirectory. Just like plain /bin/mv,
this is supposed to succeed if the mod/ parent directory exists
and fail if it doesn't exist.
Usually these tests mkdir the parent directory beforehand, but some
instead rely on it being left behind by previous tests.
More precisely, when 'git reset --hard' tries to move to a state where
mod/sub is not present any more, it would perform the following
operations:
rmdir("mod/sub")
rmdir("mod")
The first fails with ENOENT because the test script removed mod/sub
with "rm -rf" already, so 'reset --hard' doesn't bother to move on to
the second, and the mod/ directory is kept around.
Better to explicitly remove and re-create the mod/ directory so later
tests don't have to depend on the directory left behind by the earlier
ones at all (making it easier to rearrange or skip some tests in the
file or to tweak 'reset --hard' behavior without breaking unrelated
tests).
Noticed while testing a patch that fixes the reset --hard behavior
described above.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is possible that a user is trying to run a git command and fail
to realize that they are not in a git repository or working tree.
When trying to complete an operation, __git_refs would fall to a
degenerate case and attempt to use "git for-each-ref", which would
emit the error.
Hide this error message coming from "git for-each-ref".
Signed-off-by: John Szakmeister <john@szakmeister.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
