Commit Graph

47918 Commits

Author SHA1 Message Date
Junio C Hamano
49771171e5 Merge branch 'rs/pretty-add-again' into maint
The pretty-format specifiers like '%h', '%t', etc. had an
optimization that no longer works correctly.  In preparation/hope
of getting it correctly implemented, first discard the optimization
that is broken.

* rs/pretty-add-again:
  pretty: recalculate duplicate short hashes
2017-07-10 13:58:57 -07:00
Junio C Hamano
86d51bbe1a Merge branch 'ah/doc-gitattributes-empty-index' into maint
An example in documentation that does not work in multi worktree
configuration has been corrected.

* ah/doc-gitattributes-empty-index:
  doc: do not use `rm .git/index` when normalizing line endings
2017-07-10 13:58:56 -07:00
Junio C Hamano
311b760b8f Merge branch 'da/mergetools-meld-output-opt-on-macos' into maint
"git mergetool" learned to work around a wrapper MacOS X adds
around underlying meld.

* da/mergetools-meld-output-opt-on-macos:
  mergetools/meld: improve compatibiilty with Meld on macOS X
2017-07-10 13:58:56 -07:00
Junio C Hamano
c4ffd78852 Merge branch 'jk/diff-highlight-module' into maint
The 'diff-highlight' program (in contrib/) has been restructured
for easier reuse by an external project 'diff-so-fancy'.

* jk/diff-highlight-module:
  diff-highlight: split code into module
2017-07-10 13:58:56 -07:00
Junio C Hamano
5e5a7cd932 Sixteenth batch for 2.14
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 13:44:30 -07:00
Junio C Hamano
4dc59cba81 Merge branch 'jk/reflog-walk-maint'
After "git branch --move" of the currently checked out branch, the
code to walk the reflog of HEAD via "log -g" and friends
incorrectly stopped at the reflog entry that records the renaming
of the branch.

* jk/reflog-walk-maint:
  reflog-walk: include all fields when freeing complete_reflogs
  reflog-walk: don't free reflogs added to cache
  reflog-walk: duplicate strings in complete_reflogs list
  reflog-walk: skip over double-null oid due to HEAD rename
2017-07-10 13:42:53 -07:00
Junio C Hamano
e7fc60ad16 Merge branch 'bb/unicode-10.0'
Update the character width tables.

* bb/unicode-10.0:
  unicode: update the width tables to Unicode 10
2017-07-10 13:42:52 -07:00
Junio C Hamano
cd0391af93 Merge branch 'ks/typofix-commit-c-comment'
Typofix.

* ks/typofix-commit-c-comment:
  builtin/commit.c: fix a typo in the comment
2017-07-10 13:42:51 -07:00
Junio C Hamano
0c6435a4d6 Merge branch 'ab/wildmatch'
Minor code cleanup.

* ab/wildmatch:
  wildmatch: remove unused wildopts parameter
2017-07-10 13:42:51 -07:00
Junio C Hamano
2db87328ef Merge branch 'ab/sha1dc'
The "collission-detecting" implementation of SHA-1 hash we borrowed
from is replaced by directly binding the upstream project as our
submodule.  Glitches on minority platforms are still being worked out.

* ab/sha1dc:
  sha1collisiondetection: automatically enable when submodule is populated
  sha1dc: optionally use sha1collisiondetection as a submodule
2017-07-10 13:42:51 -07:00
Junio C Hamano
d73b46cfb5 Merge branch 'rs/free-and-null'
Code cleanup.

* rs/free-and-null:
  coccinelle: polish FREE_AND_NULL rules
2017-07-10 13:42:51 -07:00
Junio C Hamano
9bf8e0c73d Merge branch 'pw/unquote-path-in-git-pm'
Code refactoring.

* pw/unquote-path-in-git-pm:
  t9700: add tests for Git::unquote_path()
  Git::unquote_path(): throw an exception on bad path
  Git::unquote_path(): handle '\a'
  add -i: move unquote_path() to Git.pm
2017-07-10 13:42:50 -07:00
Junio C Hamano
c4f70d2c90 Merge branch 'ks/commit-assuming-only-warning-removal'
An old message shown in the commit log template was removed, as it
has outlived its usefulness.

* ks/commit-assuming-only-warning-removal:
  commit-template: distinguish status information unconditionally
  commit-template: remove outdated notice about explicit paths
2017-07-10 13:42:50 -07:00
Alejandro R. Sedeño
5b5c9c3e19 ref-filter.c: drop return from void function
Sun's C compiler errors out on this pattern:

void foo() { ... }
void bar() { return foo(); }

Signed-off-by: Alejandro R. Sedeño <asedeno@mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 12:34:51 -07:00
Ralf Thielow
f271c95cc0 l10n: de.po: fix typo
Reported-by: Andre Hinrichs <andre.hinrichs@gmx.de>
Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 11:44:18 -07:00
Jeff King
566cf0b3bd Makefile: disable unaligned loads with UBSan
The undefined behavior sanitizer complains about unaligned
loads, even if they're OK for a particular platform in
practice. It's possible that they _are_ a problem, of
course, but since it's a known tradeoff the UBSan errors are
just noise.

Let's quiet it automatically by building with
NO_UNALIGNED_LOADS when SANITIZE=undefined is in use.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:31 -07:00
Jeff King
ddbc8a6d3e Makefile: turn off -fomit-frame-pointer with sanitizers
The ASan manual recommends disabling this optimization, as
it can make the backtraces produced by the tool harder to
follow (and since this is a test-debug build, we don't care
about squeezing out every last drop of performance).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:30 -07:00
Jeff King
56b5db30d0 Makefile: add helper for compiling with -fsanitize
You can already build and test with ASan by doing:

  make CFLAGS=-fsanitize=address test

but there are a few slight annoyances:

  1. It's a little long to type.

  2. It override your CFLAGS completely. You'd probably
     still want -O2, for instance.

  3. It's a good idea to also turn off "recovery", which
     lets the program keep running after a problem is
     detected (with the intention of finding as many bugs as
     possible in a given run). Since Git's test suite should
     generally run without triggering any problems, it's
     better to abort immediately and fail the test when we
     do find an issue.

With this patch, all of that happens automatically when you
run:

  make SANITIZE=address test

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:29 -07:00
Jeff King
bf1ce904b7 test-lib: turn on ASan abort_on_error by default
By default, ASan will exit with code 1 when it sees an
error. This means we'll notice a problem when we expected
git to succeed, but not in a test_must_fail block.

Let's ask it to actually raise SIGABRT instead. That will
give us a signal death that test_must_fail will notice. As a
bonus, it may also leave a coredump, which can be handy for
digging into a failure.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:28 -07:00
Jeff King
d0cc5796f3 test-lib: set ASAN_OPTIONS variable before we run git
We turn off ASan's leak detection by default in the test
suite because it's too noisy. But we don't do so until
part-way through test-lib. This is before we've run any
tests, but after we do our initial "./git" to see if the
binary has even been built.

When built with clang, this seems to work fine. However,
using "gcc -fsanitize=address", the leak checker seems to
complain more aggressively:

  $ ./git
  ...
  ==5352==ERROR: LeakSanitizer: detected memory leaks
  Direct leak of 2 byte(s) in 1 object(s) allocated from:
      #0 0x7f120e7afcf8 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.3+0xc1cf8)
      #1 0x559fc2a3ce41 in do_xmalloc /home/peff/compile/git/wrapper.c:60
      #2 0x559fc2a3cf1a in do_xmallocz /home/peff/compile/git/wrapper.c:100
      #3 0x559fc2a3d0ad in xmallocz /home/peff/compile/git/wrapper.c:108
      #4 0x559fc2a3d0ad in xmemdupz /home/peff/compile/git/wrapper.c:124
      #5 0x559fc2a3d0ad in xstrndup /home/peff/compile/git/wrapper.c:130
      #6 0x559fc274535a in main /home/peff/compile/git/common-main.c:39
      #7 0x7f120dabd2b0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202b0)

This is a leak in the sense that we never free it, but it's
in a global that is meant to last the whole program. So it's
not really interesting or in need of fixing. And at any
rate, mentioning leaks outside of the test_expect blocks is
certainly unwelcome, as it pollutes stderr.

Let's bump the setting of ASAN_OPTIONS higher in test-lib.sh
to catch our initial "can we even run git?" test.  While
we're at it, we can add a comment to make it a bit less
inscrutable.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:27 -07:00
Kaartic Sivaraam
01826066b0 doc: correct a mistake in an illustration
The first illustration of the "RECOVERING FROM UPSTREAM REBASE"
section in the 'git-rebase' documentation meant to depict that
there are number of commits on the 'master' branch, but it is
longer than the 'master' branch in the following illustrations
by one commit, even though there is no resetting of 'master' to
lose that commit.

Correct it.

Signed-off-by: Kaartic Sivaraam <kaarticsivaraam91196@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 09:50:36 -07:00
René Scharfe
5e8d2729ae wt-status: use separate variable for result of shorten_unambiguous_ref
Store the pointer to the string allocated by shorten_unambiguous_ref in
a dedicated variable, short_base, and keep base unchanged.  A non-const
variable is more appropriate for such an object.  It avoids having to
cast const away on free and stops redefining the meaning of base, making
the code slightly clearer.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 09:16:37 -07:00
René Scharfe
0fae1e072a progress: show overall rate in last update
The values in struct throughput are only updated every 0.5 seconds.  If
we're all done before that time span then the final update will show a
rate of 0 bytes/s, which is misleading if some bytes had been handled.
Remember the start time and show the total throughput instead.

And avoid division by zero by enforcing a minimum time span value of 1
(unit: 1/1024th of a second).  That makes the resulting rate an
underestimation, but it's closer to the actual value than the currently
shown 0 bytes/s.

Reported-by: 積丹尼 Dan Jacobson <jidanni@jidanni.org>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-09 09:54:20 -07:00
René Scharfe
5053313562 urlmatch: use hex2chr() in append_normalized_escapes()
Simplify the code by using hex2chr() to convert and check for invalid
characters at the same time instead of doing that sequentially with
one table lookup for each.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-09 09:43:01 -07:00
René Scharfe
2d105451c0 apply: use strcmp(3) for comparing strings in gitdiff_verify_name()
We don't know the length of the C string "another".  It could be
shorter than "name", which we compare it to using memchr(3).  Call
strcmp(3) instead to avoid running over the end of the former, and
get rid of a strlen(3) call as a bonus.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-09 09:30:42 -07:00
Jeff King
7ca260abfe branch: set remote color in ref-filter branch immediately
We set the current and local branch colors at the top of the
build_format() function. Let's do the same for the remote
color. This saves a little bit of repetition, but more
importantly it puts all of the color-setting in the same
place. That makes it easier to see that we are coloring all
possibilities.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-09 09:24:43 -07:00
Jeff King
34d820ee33 branch: use BRANCH_COLOR_LOCAL in ref-filter format
Since 949af0684 (branch: use ref-filter printing APIs,
2017-01-10), git-branch's output is generated by passing a
custom format to the ref-filter code. This format forgot to
pass BRANCH_COLOR_LOCAL, meaning that local branches
(besides the current one) were never colored at all.

We can add it in the %(if) block where we decide whether the
branch is "current" or merely "local".  Note that this means
the current/local coloring is either/or. You can't set:

  [color "branch"]
  local = blue
  current = bold

and expect the current branch to be "bold blue". This
matches the pre-949af0684 behavior.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-09 09:24:42 -07:00
Jeff King
a5b3663898 branch: only perform HEAD check for local branches
When assembling the ref-filter format to show "git branch"
output, we put the "%(if)%(HEAD)" conditional at the start
of the overall format. But there's no point in checking
whether a remote branch matches HEAD, as it never will.
The check should go inside the local conditional; we
assemble that format inside the "local" strbuf.

By itself, this is just a minor optimization. But in a
future patch, we'll need this refactoring to fix
local-branch coloring.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-09 09:24:42 -07:00
Beat Bolli
7560aacd7c unicode: update the width tables to Unicode 10
Now that Unicode 10 has been announced[0], update the character
width tables to the new version.

[0] http://blog.unicode.org/2017/06/announcing-unicode-standard-version-100.html

Signed-off-by: Beat Bolli <dev+git@drbeat.li>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-07 10:33:30 -07:00
Jeff King
e30d463d45 reflog-walk: include all fields when freeing complete_reflogs
When we encounter an error adding reflogs for a walk, we try
to free any logs we have read. But we didn't free all
fields, meaning that we could in theory leak all of the
"items" array (which would consitute the bulk of the
allocated memory).

This patch adds a helper which frees all of the entries and
uses it as appropriate.

As it turns out, the leak seems impossible to trigger with
the current code. Of the three error paths that free the
complete_reflogs struct, two only kick in when the items
array is empty, and the third was removed entirely in the
previous commit.

So this patch should be a noop in terms of behavior, but it
fixes a potential maintenance headache should anybody add a
new error path and copy the partial-free code. Which is
what happened in 5026b47175 (add_reflog_for_walk: avoid
memory leak, 2017-05-04), though its leaky call was the
third one that was recently removed.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-07 09:04:34 -07:00
Jeff King
8aae3cf755 reflog-walk: don't free reflogs added to cache
The add_reflog_for_walk() function keeps a cache mapping
refnames to their reflog contents. We use a cached reflog
entry if available, and otherwise allocate and store a new
one.

Since 5026b47175 (add_reflog_for_walk: avoid memory leak,
2017-05-04), when we hit an error parsing a date-based
reflog spec, we free the reflog memory but leave the cache
entry pointing to the now-freed memory.

We can fix this by just leaving the memory intact once it
has made it into the cache. This may leave an unused entry
in the cache, but that's OK. And it means we also catch a
similar situation: we may not have allocated at all in this
invocation, but simply be pointing to a cached entry from a
previous invocation (which is relying on that entry being
present).

The new test in t1411 exercises this case and fails when run
with --valgrind or ASan.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-07 09:00:31 -07:00
Jeff King
75afe7ac87 reflog-walk: duplicate strings in complete_reflogs list
As part of the add_reflog_to_walk() function, we keep a
string_list mapping refnames to their reflog contents. This
serves as a cache so that accessing the same reflog twice
requires only a single copy of the log in memory.

The string_list is initialized via xcalloc, meaning its
strdup_strings field is set to 0. But after inserting a
string into the list, we unconditionally call free() on the
string, leaving the list pointing to freed memory. If
another reflog is added (e.g., "git log -g HEAD HEAD"), then
the second one may have unpredictable results.

The extra free was added by 5026b47175 (add_reflog_for_walk:
avoid memory leak, 2017-05-04). Though if you look
carefully, you can see that the code was buggy even before
then. If we tried to read the reflogs by time but came up
with no entries, we exited with an error, freeing the string
in that code path. So the bug was harder to trigger, but
still there.

We can fix it by just asking the string list to make a copy
of the string. Technically we could fix the problem by not
calling free() on our string (and just handing over
ownership to the string list), but there are enough
conditionals that it's quite hard to figure out which code
paths need the free and which do not. Simpler is better
here.

The new test reliably shows the problem when run with
--valgrind or ASAN.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-07 08:58:17 -07:00
Junio C Hamano
8b2efe2a0f Fifteenth batch for 2.14
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-06 18:26:13 -07:00
Junio C Hamano
6ba649e408 Merge branch 'ab/strbuf-addftime-tzname-boolify'
strbuf_addftime() is further getting tweaked.

* ab/strbuf-addftime-tzname-boolify:
  strbuf: change an always NULL/"" strbuf_addftime() param to bool
  strbuf.h comment: discuss strbuf_addftime() arguments in order
2017-07-06 18:14:47 -07:00
Junio C Hamano
eb37527ab0 Merge branch 'xz/send-email-batch-size'
"git send-email" learned to overcome some SMTP server limitation
that does not allow many pieces of e-mails to be sent over a single
session.

* xz/send-email-batch-size:
  send-email: --batch-size to work around some SMTP server limit
2017-07-06 18:14:46 -07:00
Junio C Hamano
ccce1e51e8 Merge branch 'js/t5534-rev-parse-gives-multi-line-output-fix'
A few tests that tried to verify the contents of push certificates
did not use 'git rev-parse' to formulate the line to look for in
the certificate correctly.

* js/t5534-rev-parse-gives-multi-line-output-fix:
  t5534: fix misleading grep invocation
2017-07-06 18:14:46 -07:00
Junio C Hamano
2f4bcd8b70 Merge branch 'sb/merge-recursive-code-cleanup'
Code clean-up.

* sb/merge-recursive-code-cleanup:
  merge-recursive: use DIFF_XDL_SET macro
2017-07-06 18:14:45 -07:00
Junio C Hamano
f9b3252b2a Merge branch 'rs/apply-avoid-over-reading'
Code clean-up to fix possible buffer over-reading.

* rs/apply-avoid-over-reading:
  apply: use starts_with() in gitdiff_verify_name()
2017-07-06 18:14:45 -07:00
Junio C Hamano
cbb8704adb Merge branch 'ab/sha1dc-maint'
Update the sha1dc again to fix portability glitches.

* ab/sha1dc-maint:
  sha1dc: update from upstream
2017-07-06 18:14:44 -07:00
Junio C Hamano
62458ea333 Merge branch 'jc/utf8-fprintf'
Code cleanup.

* jc/utf8-fprintf:
  submodule--helper: do not call utf8_fprintf() unnecessarily
2017-07-06 18:14:44 -07:00
Junio C Hamano
8f58a34cad Merge branch 'js/fsck-name-object'
Test fix.

* js/fsck-name-object:
  t1450: use egrep for regexp "alternation"
2017-07-06 18:14:43 -07:00
Junio C Hamano
33cc9cfc3d Merge branch 'aw/contrib-subtree-doc-asciidoctor'
The Makefile rule in contrib/subtree for building documentation
learned to honour USE_ASCIIDOCTOR just like the main documentation
set does.

* aw/contrib-subtree-doc-asciidoctor:
  subtree: honour USE_ASCIIDOCTOR when set
2017-07-06 18:14:42 -07:00
Kaartic Sivaraam
669638fe7a builtin/commit.c: fix a typo in the comment
Signed-off-by: Kaartic Sivaraam <kaarticsivaraam91196@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-06 09:06:26 -07:00
Torsten Bögershausen
496f256989 cygwin: allow pushing to UNC paths
cygwin can use an UNC path like //server/share/repo

 $ cd //server/share/dir
 $ mkdir test
 $ cd test
 $ git init --bare

 However, when we try to push from a local Git repository to this repo,
 there is a problem: Git converts the leading "//" into a single "/".

 As cygwin handles an UNC path so well, Git can support them better:

 - Introduce cygwin_offset_1st_component() which keeps the leading "//",
   similar to what Git for Windows does.

 - Move CYGWIN out of the POSIX in the tests for path normalization in t0060

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-05 14:01:03 -07:00
Junio C Hamano
50ff9ea4a0 Fourteenth batch for 2.14
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-05 13:33:51 -07:00
Junio C Hamano
00b7cf2379 Merge branch 'jt/unify-object-info'
Code clean-ups.

* jt/unify-object-info:
  sha1_file: refactor has_sha1_file_with_flags
  sha1_file: do not access pack if unneeded
  sha1_file: teach sha1_object_info_extended more flags
  sha1_file: refactor read_object
  sha1_file: move delta base cache code up
  sha1_file: rename LOOKUP_REPLACE_OBJECT
  sha1_file: rename LOOKUP_UNKNOWN_OBJECT
  sha1_file: teach packed_object_info about typename
2017-07-05 13:32:57 -07:00
Junio C Hamano
8e90578ffb Merge branch 'cc/shared-index-permfix'
The split index code did not honor core.sharedrepository setting
correctly.

* cc/shared-index-permfix:
  t1700: make sure split-index respects core.sharedrepository
  t1301: move modebits() to test-lib-functions.sh
  read-cache: use shared perms when writing shared index
2017-07-05 13:32:57 -07:00
Junio C Hamano
5ab148dda0 Merge branch 'rs/sha1-name-readdir-optim'
Optimize "what are the object names already taken in an alternate
object database?" query that is used to derive the length of prefix
an object name is uniquely abbreviated to.

* rs/sha1-name-readdir-optim:
  sha1_file: guard against invalid loose subdirectory numbers
  sha1_file: let for_each_file_in_obj_subdir() handle subdir names
  p4205: add perf test script for pretty log formats
  sha1_name: cache readdir(3) results in find_short_object_filename()
2017-07-05 13:32:56 -07:00
Junio C Hamano
85ce4a6828 Merge branch 'bw/repo-object'
Introduce a "repository" object to eventually make it easier to
work in multiple repositories (the primary focus is to work with
the superproject and its submodules) in a single process.

* bw/repo-object:
  ls-files: use repository object
  repository: enable initialization of submodules
  submodule: convert is_submodule_initialized to work on a repository
  submodule: add repo_read_gitmodules
  submodule-config: store the_submodule_cache in the_repository
  repository: add index_state to struct repo
  config: read config from a repository object
  path: add repo_worktree_path and strbuf_repo_worktree_path
  path: add repo_git_path and strbuf_repo_git_path
  path: worktree_git_path() should not use file relocation
  path: convert do_git_path to take a 'struct repository'
  path: convert strbuf_git_common_path to take a 'struct repository'
  path: always pass in commondir to update_common_dir
  path: create path.h
  environment: store worktree in the_repository
  environment: place key repository state in the_repository
  repository: introduce the repository object
  environment: remove namespace_len variable
  setup: add comment indicating a hack
  setup: don't perform lazy initialization of repository state
2017-07-05 13:32:56 -07:00
Jeff King
2272d3e542 reflog-walk: skip over double-null oid due to HEAD rename
Since 39ee4c6c2f (branch: record creation of renamed branch
in HEAD's log, 2017-02-20), a rename on the currently
checked out branch will create two entries in the HEAD
reflog: one where the branch goes away (switching to the
null oid), and one where it comes back (switching away from
the null oid).

This confuses the reflog-walk code. When walking backwards,
it first sees the null oid in the "old" field of the second
entry. Thanks to the "root commit" logic added by 71abeb753f
(reflog: continue walking the reflog past root commits,
2016-06-03), we keep looking for the next entry by scanning
the "new" field from the previous entry. But that field is
also null! We need to go just a tiny bit further, and look
at its "old" field. But with the current code, we decide the
reflog has nothing else to show and just give up. To the
user this looks like the reflog was truncated by the rename
operation, when in fact those entries are still there.

This patch does the absolute minimal fix, which is to look
back that one extra level and keep traversing.

The resulting behavior may not be the _best_ thing to do in
the long run (for example, we show both reflog entries each
with the same commit id), but it's a simple way to fix the
problem without risking further regressions.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-05 10:34:00 -07:00