completion: offer ctags symbol names for 'git log -S', '-G' and '-L:'

Just like in the case of search patterns for 'git grep', see 29eec71f2
(completion: match ctags symbol names in grep patterns, 2011-10-21)),
a common thing to look for using 'git log -S', '-G' and '-L:' is the
name of a symbol.

Teach the completion for 'git log' to offer ctags symbol names after
these options, both in stuck and in unstuck forms.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: extract completing ctags symbol names into helper function

The previous commit doubled the number of __git_match_ctag()'s
positional parameters, and, to keep the position of existing
parameters for the sake of backwards compatibility, the prefix,
current word and suffix parameters ended up in different order than in
other functions accepting the same parameters. Then there is a
condition checking the existence of the tag file before invoking this
function.

We could still live with this if there were only a single callsite,
but the next commit will add a few more, so it's worth providing a
cleaner interface.

Add the wrapper function __git_complete_symbol(), which encompasses
the condition for checking the presence of the tag file and filling
COMPREPLY, and accepts '--opt=val'-style options with default values
that keep callsites simpler.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: put matching ctags symbol names directly into COMPREPLY

The one-liner awk script in __git_match_ctag() listing ctags symbol
names for 'git grep <TAB>' is already smart enough to list only symbol
names matching the current word to be completed.

Extend this helper function to accept prefix and suffix parameters to
be prepended and appended, respectively, to each listed symbol name in
the awk script, so its output won't require any additional processing
or filtering in the completion script before being handed over to
Bash. Use the faster __gitcomp_direct() helper instead of
__gitcomp_nl() to fill the fully processed matching symbol names into
Bash's COMPREPLY array.

Right after 'git grep <TAB>' in current git.git with 14k+ symbol names
in the tag file, best of five:

Before:

$ time __gitcomp_nl "$(__git_match_ctag "" tags)"

real 0m0.178s
user 0m0.176s
sys 0m0.000s

After:

$ time __gitcomp_direct "$(__git_match_ctag "" tags "" " ")"

real 0m0.058s
user 0m0.048s
sys 0m0.008s

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: speed up branch and tag completion

Modify __git_heads() and __git_tags() and the few callsites they have,
so we can let 'git for-each-ref' do all the hard work and these
functions' output won't need any further processing or filtering
before being handed over to Bash, resulting in faster branch and tag
completion. These are some of the same tricks used in the previous
commits to speed up refs completion, namely:

- Extend both functions to accept prefix, current word and suffix
positional parameters, all optional and all empty by default to
keep the parameterless behavior unaltered.

- Specify appropriate globbing patterns to 'git for-each-ref' to
list only branches or tags matching the given current word
parameter.

- Modify the 'git for-each-ref --format=<...>' to include the given
prefix and suffix.

- Adjust all callsites to specify the proper prefix, current word
and suffix parameters, and to fill COMPREPLY using
__gitcomp_direct().

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: fill COMPREPLY directly when completing fetch refspecs

The __git_complete_fetch_refspecs() has to iterate over __git_refs()'s
output anyway to turn the listed matching refs into refspecs, and it
knows about the prefix and suffix that has to be added to each
refspec.

Modify this function to add the prefix and suffix to each refspec
while iterating and feed the result, since it doesn't need further
processing, to the new __gitcomp_direct() helper added in the previous
commit, because it should be faster when there are a lot of refspecs
to list.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: fill COMPREPLY directly when completing refs

__gitcomp_nl() iterates over all the possible completion words it gets
as argument

- filtering matching words,
- appending a trailing space to each matching word (in all but two
cases),
- prepending a prefix to each matching word (when completing words
after e.g. '--option=<TAB>' or 'master..<TAB>'), and
- adding each matching word to the COMPREPLY array.

This takes a while when a lot of refs are passed to __gitcomp_nl().

The previous changes in this series ensure that __git_refs() lists
only refs matching the current word to be completed, making a second
filtering in __gitcomp_nl() redundant.

Adding the necessary prefix and suffix could be done in __git_refs()
as well:

- When refs come from 'git for-each-ref', then that prefix and
suffix could be added much more efficiently using a 'git
for-each-ref' format containing said prefix and suffix. Care
should be taken, though, because that prefix might contain
'for-each-ref' format specifiers as part of the left hand side of
a '..' range or '...' symmetric difference notation or
fetch/push/etc. refspec, e.g. 'git log "evil-%(refname)..br<TAB>'.
Doubling every '%' in the prefix will prevent 'git for-each-ref'
from interpolating any of those contained specifiers.
- When refs come from 'git ls-remote', then that prefix and suffix
can be added in the shell loop that has to process 'git
ls-remote's output anyway.
- Finally, the prefix and suffix can be added to that handful of
potentially matching symbolic and pseudo refs right away in the
shell loop listing them.

And then all what is still left to do is to assign a bunch of
newline-separated words to a shell array, which can be done without a
shell loop iterating over each word, basically making all of
__gitcomp_nl() unnecessary for refs completion.

Add the helper function __gitcomp_direct() to fill the COMPREPLY array
with prefiltered and preprocessed words without any additional
processing, without a shell loop, with just one single compound
assignment. Modify __git_refs() to accept prefix and suffix
parameters and add them to each and every listed ref as described
above. Modify __git_complete_refs() to pass the prefix and suffix
parameters to __git_refs() and to feed __git_refs()'s output to
__gitcomp_direct() instead of __gitcomp_nl().

This speeds up refs completion when there are a lot of refs matching
the current word to be completed. Listing all branches for completion
in a repo with 100k local branches, all packed, best of five:

On Linux, near the beginning of this series, for reference:

$ time __git_complete_refs

real 0m2.028s
user 0m1.692s
sys 0m0.344s

Before this patch:

real 0m1.135s
user 0m1.112s
sys 0m0.024s

After:

real 0m0.367s
user 0m0.352s
sys 0m0.020s

On Windows, near the beginning:

real 0m13.078s
user 0m1.609s
sys 0m0.060s

Before this patch:

real 0m2.093s
user 0m1.641s
sys 0m0.060s

After:

real 0m0.683s
user 0m0.203s
sys 0m0.076s

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: let 'for-each-ref' sort remote branches for 'checkout' DWIMery

When listing unique remote branches for 'git checkout's tracking
DWIMery, __git_refs() runs the classic '... |sort |uniq -u' pattern to
filter out duplicate remote branches.

Let 'git for-each-ref' do the sorting, sparing the overhead of
fork()+exec()ing 'sort' and a stage in the pipeline where potentially
relatively large amount of data can be passed between two subsequent
pipeline stages.

This speeds up refs completion for 'git checkout' a bit when a lot of
remote branches match the current word to be completed. Listing a
single local and 100k remote branches, all packed, best of five:

On Linux, before:

$ time __git_complete_refs --track

real 0m1.856s
user 0m1.816s
sys 0m0.060s

After:

real 0m1.550s
user 0m1.512s
sys 0m0.060s

On Windows, before:

real 0m3.128s
user 0m2.155s
sys 0m0.183s

After:

real 0m2.781s
user 0m1.826s
sys 0m0.136s

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: let 'for-each-ref' filter remote branches for 'checkout' DWIMery

The code listing unique remote branches for 'git checkout's tracking
DWIMery outputs only remote branches that match the current word to be
completed, but the filtering is done in a shell loop iterating over
all remote refs.

Let 'git for-each-ref' do the filtering, as it can do so much more
efficiently and we can remove that shell loop entirely.

This speeds up refs completion for 'git checkout' considerably when
there are a lot of non-matching remote refs to be filtered out.
Uniquely completing a branch in a repository with 100k remote
branches, all packed, best of five:

On Linux, before:

$ time __git_complete_refs --cur=maste --track

real 0m1.993s
user 0m1.740s
sys 0m0.304s

After:

real 0m0.266s
user 0m0.248s
sys 0m0.012s

On Windows, before:

real 0m6.187s
user 0m3.358s
sys 0m2.121s

After:

real 0m0.750s
user 0m0.015s
sys 0m0.090s

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: let 'for-each-ref' strip the remote name from remote branches

The code listing unique remote branches for 'git checkout's tracking
DWIMery uses a shell parameter expansion in a loop iterating over each
listed ref to remove the remote's name from the remote branches, i.e.
the leading path component from the short ref. When listing refs from
a configured remote repository, '| sed s///' is used for the same
purpose.

Let 'git for-each-ref' strip one more leading path component from the
refs, i.e. use the format 'refname:strip=3' instead of '=2', making
that parameter expansion and 'sed' execution unnecessary.

This speeds up refs completion for 'git checkout'. Uniquely
completing a branch for 'git checkout maste<TAB>' in a repo with 100k
remote branches, all packed, best of five:

On Linux, near the beginning of this series, for reference:

$ time __git_complete_refs --cur=maste --track

real 0m8.185s
user 0m6.896s
sys 0m1.616s

Before this patch:

real 0m2.714s
user 0m2.344s
sys 0m0.436s

After:

real 0m1.993s
user 0m1.740s
sys 0m0.304s

On Windows, near the beginning:

real 1m8.421s
user 0m7.591s
sys 0m3.557s

Before this patch:

real 0m8.191s
user 0m4.638s
sys 0m2.918s

After:

real 0m6.187s
user 0m3.358s
sys 0m2.121s

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: let 'for-each-ref' and 'ls-remote' filter matching refs

When completing refs, several __git_refs() code paths list all the
refs from the refs/{heads,tags,remotes}/ hierarchy and then
__gitcomp_nl() iterates over those refs in a shell loop to filter out
refs not matching the current ref to be completed. This comes with a
considerable performance penalty when a repository contains a lot of
refs but the current ref can be uniquely completed or when only a
handful of refs match the current ref.

Reduce the number of iterations in __gitcomp_nl() from the number of
refs to the number of matching refs by specifying appropriate globbing
patterns to 'git for-each-ref' and 'git ls-remote' to list only those
refs that match the current ref to be completed. However, do so only
when the ref to match is explicitly given as parameter, because the
current word on the command line might contain a prefix like
'--option=' or 'branch..'. The __git_complete_refs() and
__git_complete_fetch_refspecs() helpers introduced previously in this
patch series already call __git_refs() specifying this current ref
parameter, so all their callsites, i.e. all places in the completion
script doing refs completion, can benefit from this optimization.

Furthermore, list only those symbolic and pseudo refs that match the
current ref to be completed. Though it doesn't matter at all in
itself performance-wise, it will allow us further significant
optimizations later in this series.

This speeds up refs completion considerably when there are a lot of
non-matching refs to be filtered out. Uniquely completing a branch in
a repository with 100k local branches, all packed, best of five:

On Linux, before:

$ time __git_complete_refs --cur=maste

real 0m0.831s
user 0m0.808s
sys 0m0.028s

After:

real 0m0.119s
user 0m0.104s
sys 0m0.008s

On Windows, before:

real 0m1.480s
user 0m1.031s
sys 0m0.060s

After:

real 0m0.377s
user 0m0.015s
sys 0m0.030s

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: don't disambiguate short refs

When the completion script lists short refs it does so using the 'git
for-each-ref' format 'refname:short', which makes sure that all listed
refs are unambiguous. While disambiguating refs is technically
correct in this case, as opposed to the cases discussed in the
previous patch, this disambiguation involves several stat() syscalls
for each ref, thus, unfortunately, comes at a steep cost especially on
Windows and/or when there are a lot of refs to be listed. A user of
Git for Windows reported[1] 'git checkout <TAB>' taking ~11 seconds in
a repository with just about 4000 refs.

However, it's questionable whether ambiguous refs are really that bad
to justify that much extra cost:

- Ambiguous refs are not that common,
- even if a repository contains ambiguous refs, they only hurt when
the user actually happens to want to do something with one of the
ambiguous refs, and
- the issue can be easily circumvented by renaming those ambiguous
refs.

- On the other hand, apparently not that many refs are needed to
make refs completion unacceptably slow on Windows,
- and this slowness bites each and every time the user attempts refs
completion, even when the repository doesn't contain any ambiguous
refs.
- Furthermore, circumventing the issue might not be possible or
might be considerably more difficult and requires various
trade-offs (e.g. working in a repository with only a few selected
important refs while keeping a separate repository with all refs
for reference).

Arguably, in this case the benefits of technical correctness are
rather minor compared to the price we pay for it, and we are better
off opting for performance over correctness.

Use the 'git for-each-ref' format 'refname:strip=2' to list short refs
to spare the substantial cost of disambiguating.

This speeds up refs completion considerably. Uniquely completing a
branch in a repository with 100k local branches, all packed, best of
five:

On Linux, before:

$ time __git_complete_refs --cur=maste

real 0m1.662s
user 0m1.368s
sys 0m0.296s

After:

real 0m0.831s
user 0m0.808s
sys 0m0.028s

On Windows, before:

real 0m12.457s
user 0m1.016s
sys 0m0.092s

After:

real 0m1.480s
user 0m1.031s
sys 0m0.060s

[1] - https://github.com/git-for-windows/git/issues/524

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: don't disambiguate tags and branches

When the completion script has to list only tags or only branches, it
uses the 'git for-each-ref' format 'refname:short', which makes sure
that all listed tags and branches are unambiguous. However,
disambiguating tags and branches in these cases is wrong, because:

- __git_tags(), the helper function listing possible tagname
arguments for 'git tag', lists an ambiguous tag
'refs/tags/ambiguous' as 'tags/ambiguous'. Its only consumer,
'git tag' expects its tagname argument to be under 'refs/tags/',
thus it interprets that abgiguous tag as
'refs/tags/tags/ambiguous'. Clearly wrong.

- __git_heads() lists possible branchname arguments for 'git branch'
and possible 'branch.<branchname>' configuration subsections.
Both of these expect branchnames to be under 'refs/heads/' and
misinterpret a disambiguated branchname like 'heads/ambiguous'.

Furthermore, disambiguation involves several stat() syscalls for each
tag or branch, thus comes at a steep cost especially on Windows and/or
when there are a lot of tags or branches to be listed.

Use the 'git for-each-ref' format 'refname:strip=2' instead of
'refname:short' to avoid harmful disambiguation of tags and branches
in __git_tags() and __git_heads().

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: support excluding full refs

Commit 49416ad22 (completion: support excluding refs, 2016-08-24) made
possible to complete short refs with a '^' prefix.

Extend the support to full refs to make completing '^refs/...' work.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: support completing fully qualified non-fast-forward refspecs

After 'git fetch <remote> <TAB>' our completion script offers refspecs
that will fetch to a local branch with the same name as in the remote
repository, e.g. 'master:master'. This also completes
non-fast-forward refspecs, i.e. after a '+' prefix like
'+master:master', and fully qualified refspecs, e.g.
'refs/heads/master:refs/heads/master'. However, it does not complete
non-fast-forward fully qualified refspecs (or fully qualified refspecs
following any other prefix, e.g. '--option=', though currently no git
command supports such an option, but third party git commands might).

These refspecs are listed by the __git_refs2() function, which is just
a thin wrapper iterating over __git_refs()'s output, turning each
listed ref into a refspec. Now, it's certainly possible to modify
__git_refs2() and its callsite to pass an extra parameter containing
only the ref part of the current word to be completed (to follow suit
of the previous commit) to deal with prefixed fully qualified refspecs
as well. Unfortunately, keeping the current behavior unchanged in the
"no extra parameter" case brings in a bit of subtlety, which makes the
resulting code ugly and compelled me to write a 8-line long comment in
the proof of concept. Not good. However, since the callsite has to
be modified for proper functioning anyway, we might as well leave
__git_refs2() as is and introduce a new helper function without
backwards compatibility concerns.

Add the new function __git_complete_fetch_refspecs() that has all the
necessary parameters to do the right thing in all cases mentioned
above, including non-fast-forward fully qualified refspecs. This new
function can also easier benefit from optimizations coming later in
this patch series.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: support completing full refs after '--option=refs/<TAB>'

Completing full refs currently only works when the full ref stands on
in its own on the command line, but doesn't work when the current word
to be completed contains a prefix before the full ref, e.g.
'--option=refs/<TAB>' or 'master..refs/bis<TAB>'.

The reason is that __git_refs() looks at the current word to be
completed ($cur) as a whole to decide whether it has to list full (if
it starts with 'refs/') or short refs (otherwise). However, $cur also
holds said '--option=' or 'master..' prefixes, which of course throw
off this decision. Luckily, the default action is to list short refs,
that's why completing short refs happens to work even after a
'master..<TAB>' prefix and similar cases.

Pass only the ref part of the current word to be completed to
__git_refs() as a new positional parameter, so it can make the right
decision even if the whole current word contains some kind of a
prefix.

Make this new parameter the 4. positional parameter and leave the 3.
as an ignored placeholder for now (it will be used later in this patch
series).

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: wrap __git_refs() for better option parsing

__git_refs() currently accepts two optional positional parameters: a
remote and a flag for 'git checkout's tracking DWIMery. To fix a
minor bug, and, more importantly, for faster refs completion, this
series will add three more parameters: a prefix, the current word to
be completed and a suffix, i.e. the options accepted by __gitcomp() &
friends, and will change __git_refs() to list only refs matching that
given current word and to add that given prefix and suffix to the
listed refs.

However, __git_refs() is the helper function that is most likely used
in users' custom completion scriptlets for their own git commands, and
we don't want to break those, so

- we can't change __git_refs()'s default output format, i.e. we
can't by default append a trailing space to every listed ref,
meaning that the suffix parameter containing the default trailing
space would have to be specified on every invocation, and

- we can't change the position of existing positional parameters
either, so there would have to be plenty of set-but-empty
placeholder positional parameters all over the completion script.

Furthermore, with five positional parameters it would be really hard
to remember which position means what.

To keep callsites simple, add the new wrapper function
__git_complete_refs() around __git_refs(), which:

- instead of positional parameters accepts real '--opt=val'-style
options and with minimalistic option parsing translates them to
__git_refs()'s and __gitcomp_nl()'s positional parameters, and

- includes the '__gitcomp_nl "$(__git_refs ...)" ...' command
substitution to make its behavior match its name and the behavior
of other __git_complete_* functions, and to limit future changes
in this series to __git_refs() and this new wrapper function.

Call this wrapper function instead of __git_refs() wherever possible
throughout the completion script, i.e. when __git_refs()'s output is
fed to __gitcomp_nl() right away without further processing, which
means all callsites except a single one in the __git_refs2() helper.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: remove redundant __gitcomp_nl() options from _git_commit()

Those two options are specifying the default values that
__gitcomp_nl() would use anyway when invoked with no options at all.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: restore removed line continuating backslash

Recent commit 1cd23e9e0 (completion: don't use __gitdir() for git
commands, 2017-02-03) rewrapped a couple of long lines, and while
doing so it inadvertently removed a '\' from the end of a line, thus
breaking completion for 'git config remote.name.push <TAB>'.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: cache the path to the repository

After the previous changes in this series there are only a handful of
$(__gitdir) command substitutions left in the completion script, but
there is still a bit of room for improvements:

1. The command substitution involves the forking of a subshell,
which has considerable overhead on some platforms.

2. There are a few cases, where this command substitution is
executed more than once during a single completion, which means
multiple subshells and possibly multiple 'git rev-parse'
executions. __gitdir() is invoked twice while completing refs
for e.g. 'git log', 'git rebase', 'gitk', or while completing
remote refs for 'git fetch' or 'git push'.

Both of these points can be addressed by using the
__git_find_repo_path() helper function introduced in the previous
commit:

1. __git_find_repo_path() stores the path to the repository in a
variable instead of printing it, so the command substitution
around the function can be avoided. Or rather: the command
substitution should be avoided to make the new value of the
variable set inside the function visible to the callers.
(Yes, there is now a command substitution inside
__git_find_repo_path() around each 'git rev-parse', but that's
executed only if necessary, and only once per completion, see
point 2. below.)

2. $__git_repo_path, the variable holding the path to the
repository, is declared local in the toplevel completion
functions __git_main() and __gitk_main(). Thus, once set, the
path is visible in all completion functions, including all
subsequent calls to __git_find_repo_path(), meaning that they
wouldn't have to re-discover the path to the repository.

So call __git_find_repo_path() and use $__git_repo_path instead of the
$(__gitdir) command substitution to access paths in the .git
directory. Turn tests checking __gitdir()'s repository discovery into
tests of __git_find_repo_path() such that only the tested function
changes but the expected results don't, ensuring that repo discovery
keeps working as it did before.

As __gitdir() is not used anymore in the completion script, mark it as
deprecated and direct users' attention to __git_find_repo_path() and
$__git_repo_path. Yet keep four __gitdir() tests to ensure that it
handles success and failure of __git_find_repo_path() and that it
still handles its optional remote argument, because users' custom
completion scriptlets might depend on it.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: extract repository discovery from __gitdir()

To prepare for caching the path to the repository in the following
commit, extract the repository discovering part of __gitdir() into the
__git_find_repo_path() helper function, which stores the found path in
the $__git_repo_path variable instead of printing it. Make __gitdir()
a wrapper around this new function. Declare $__git_repo_path local in
the toplevel completion functions __git_main() and __gitk_main() to
ensure that it never leaks into the environment and influences
subsequent completions (though this isn't necessary right now, as
__gitdir() is still only executed in subshells, but will matter for
the following commit).

Adjust tests checking __gitdir() or any other completion function
calling __gitdir() to perform those checks in a subshell to prevent
$__git_repo_path from leaking into the test environment. Otherwise
leave the tests unchanged to demonstrate that this change doesn't
alter __gitdir()'s behavior.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: don't guard git executions with __gitdir()

Three completion functions, namely __git_index_files(), __git_heads()
and __git_tags(), first run __gitdir() and check that the path it
outputs exists, i.e. that there is a git repository, and run a git
command only if there is one.

After the previous changes in this series there are no further uses of
__gitdir()'s output in these functions besides those checks. And
those checks are unnecessary, because we can just execute those git
commands outside of a repository and let them error out. We don't
perform such a check in other places either.

Remove this check and the __gitdir() call from these functions,
sparing the fork()+exec() overhead of the command substitution and the
potential 'git rev-parse' execution.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: consolidate silencing errors from git commands

Outputting error messages during completion is bad: they disrupt the
command line, can't be deleted, and the user is forced to Ctrl-C and
start over most of the time. We already silence stderr of many git
commands in our Bash completion script, but there are still some in
there that can spew error messages when something goes wrong.

We could add the missing stderr redirections to all the remaining
places, but instead let's leverage that git commands are now executed
through the previously introduced __git() wrapper function, and
redirect standard error to /dev/null only in that function. This way
we need only one redirection to take care of errors from almost all
git commands. Redirecting standard error of the __git() wrapper
function thus became redundant, remove them.

The exceptions, i.e. the repo-independent git executions and those in
the __gitdir() function that don't go through __git() already have
their standard error silenced.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: don't use __gitdir() for git commands

Several completion functions contain the following pattern to run git
commands respecting the path to the repository specified on the
command line:

git --git-dir="$(__gitdir)" <cmd> <options>

This imposes the overhead of fork()ing a subshell for the command
substitution and potentially fork()+exec()ing 'git rev-parse' inside
__gitdir().

Now, if neither '--gitdir=<path>' nor '-C <path>' options are
specified on the command line, then those git commands are perfectly
capable to discover the repository on their own. If either one or
both of those options are specified on the command line, then, again,
the git commands could discover the repository, if we pass them all of
those options from the command line.

This means we don't have to run __gitdir() at all for git commands and
can spare its fork()+exec() overhead.

Use Bash parameter expansions to check the $__git_dir variable and
$__git_C_args array and to assemble the appropriate '--git-dir=<path>'
and '-C <path>' options if either one or both are present on the
command line. These parameter expansions are, however, rather long,
so instead of changing all git executions and make already long lines
even longer, encapsulate running git with '--git-dir=<path> -C <path>'
options into the new __git() wrapper function. Furthermore, this
wrapper function will also enable us to silence error messages from
git commands uniformly in one place in a later commit.

There's one tricky case, though: in __git_refs() local refs are listed
with 'git for-each-ref', where "local" is not necessarily the
repository we are currently in, but it might mean a remote repository
in the filesystem (e.g. listing refs for 'git fetch /some/other/repo
<TAB>'). Use one-shot variable assignment to override $__git_dir with
the path of the repository where the refs should come from. Although
one-shot variable assignments in front of shell functions are to be
avoided in our scripts in general, in the Bash completion script we
can do that safely.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: respect 'git -C <path>'

'git -C <path>' option(s) on the command line should be taken into
account during completion, because

- like '--git-dir=<path>', it can lead us to a different repository,

- a few git commands executed in the completion script do care about
in which directory they are executed, and

- the command for which we are providing completion might care about
in which directory it will be executed.

However, unlike '--git-dir=<path>', the '-C <path>' option can be
specified multiple times and their effect is cumulative, so we can't
just store a single '<path>' in a variable. Nor can we simply
concatenate a path from '-C <path1> -C <path2> ...', because e.g. (in
an arguably pathological corner case) a relative path might be
followed by an absolute path.

Instead, store all '-C <path>' options word by word in the
$__git_C_args array in the main git completion function, and pass this
array, if present, to 'git rev-parse --absolute-git-dir' when
discovering the repository in __gitdir(), and let it take care of
multiple options, relative paths, absolute paths and everything.

Also pass all '-C <path> options via the $__git_C_args array to those
git executions which require a worktree and for which it matters from
which directory they are executed from. There are only three such
cases:

- 'git diff-index' and 'git ls-files' in __git_ls_files_helper()
used for git-aware filename completion, and

- the 'git ls-tree' used for completing the 'ref:path' notation.

The other git commands executed in the completion script don't need
these '-C <path>' options, because __gitdir() already took those
options into account. It would not hurt them, either, but let's not
induce unnecessary code churn.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rev-parse: add '--absolute-git-dir' option

The output of 'git rev-parse --git-dir' can be either a relative or an
absolute path, depending on whether the current working directory is
at the top of the worktree or the .git directory or not, or how the
path to the repository is specified via the '--git-dir=<path>' option
or the $GIT_DIR environment variable. And if that output is a
relative path, then it is relative to the directory where any 'git
-C <path>' options might have led us.

This doesn't matter at all for regular scripts, because the git
wrapper automatically takes care of changing directories according to
the '-C <path>' options, and the scripts can then simply follow any
path returned by 'git rev-parse --git-dir', even if it's a relative
path.

Our Bash completion script, however, is unique in that it must run
directly in the user's interactive shell environment. This means that
it's not executed through the git wrapper and would have to take care
of any '-C <path> options on its own, and it can't just change
directories as it pleases. Consequently, adding support for taking
any '-C <path>' options on the command line into account during
completion turned out to be considerably more difficult, error prone
and required more subshells and git processes when it had to cope with
a relative path to the .git directory.

Help this rather special use case and teach 'git rev-parse' a new
'--absolute-git-dir' option which always outputs a canonicalized
absolute path to the .git directory, regardless of whether the path is
discovered automatically or is specified via $GIT_DIR or 'git
--git-dir=<path>'.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: fix completion after 'git -C <path>'

The main completion function finds the name of the git command by
iterating through all the words on the command line in search for the
first non-option-looking word. As it is not aware of 'git -C's
mandatory path argument, if the '-C <path>' option is present, 'path'
will be the first such word and it will be mistaken for a git command.
This breaks completion in various ways:

- If 'path' happens to match one of the commands supported by the
completion script, then options of that command will be offered.

- If 'path' doesn't match a supported command and doesn't contain any
characters not allowed in Bash identifier names, then the
completion script does basically nothing and Bash in turn falls
back to filename completion for all subsequent words.

- Otherwise, if 'path' does contain such an unallowed character, then
it leads to a more or less ugly error message in the middle of the
command line. The standard '/' directory separator is such a
character, and it happens to trigger one of the uglier errors:

$ git -C some/path <TAB>sh.exe": declare: `_git_some/path': not a valid identifier
error: invalid key: alias.some/path

Fix this by skipping 'git -C's mandatory path argument while iterating
over the words on the command line. Extend the relevant test with
this case and, while at it, with cases that needed similar treatment
in the past ('--git-dir', '-c', '--work-tree' and '--namespace').

Additionally, silence the standard error of the 'declare' builtins
looking for the completion function associated with the git command
and of the 'git config' query for the aliased command. So if git ever
learns a new option with a mandatory argument in the future, then,
though the completion script will again misbehave, at least the
command line will not be utterly disrupted by those error messages.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: don't offer commands when 'git --opt' needs an argument

The main git options '--git-dir', '-c', '-C', '--worktree' and
'--namespace' require an argument, but attempting completion right
after them lists git commands.

Don't offer anything right after these options, thus let Bash fall
back to filename completion, because

- the three options '--git-dir', '-C' and '--worktree' do actually
require a path argument, and

- we don't complete the required argument of '-c' and '--namespace',
and in that case the "standard" behavior of our completion script
is to not offer anything, but fall back to filename completion.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: list short refs from a remote given as a URL

e832f5c09680 (completion: avoid ls-remote in certain scenarios,
2013-05-28) turned a 'git ls-remote <remote>' query into a 'git
for-each-ref refs/remotes/<remote>/' to improve responsiveness of
remote refs completion by avoiding potential network communication.
However, it inadvertently made impossible to complete short refs from
a remote given as a URL, e.g. 'git fetch git://server.com/repo.git
<TAB>', because there is, of course, no such thing as
'refs/remotes/git://server.com/repo.git'.

Since the previous commit we tell apart configured remotes, i.e. those
that can have a hierarchy under 'refs/remotes/', from others that
don't, including remotes given as URL, so we know when we can't use
the faster 'git for-each-ref'-based approach.

Resurrect the old, pre-e832f5c09680 'git ls-remote'-based code for the
latter case to support listing short refs from remotes given as a URL.
The code is slightly updated from the original to

- take into account the path to the repository given on the command
line (if any), and
- omit 'ORIG_HEAD' from the query, as 'git ls-remote' will never
list it anyway.

When the remote given to __git_refs() doesn't exist, then it will be
handled by this resurrected 'git ls-remote' query. This code path
doesn't list 'HEAD' unconditionally, which has the nice side effect of
fixing two more expected test failures.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: don't list 'HEAD' when trying refs completion outside of a repo

When refs completion is attempted while not in a git repository, the
completion script offers 'HEAD' erroneously.

Check early in __git_refs() that there is either a repository or a
remote to work on, and return early if neither is given.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: list refs from remote when remote's name matches a directory

If the remote given to __git_refs() happens to match both the name of
a configured remote and the name of a directory in the current working
directory, then that directory is assumed to be a git repository, and
listing refs from that directory will be attempted. This is wrong,
because in such a situation git commands (e.g. 'git fetch|pull|push
<remote>' whom these refs will eventually be passed to) give
precedence to the configured remote. Therefore, __git_refs() should
list refs from the configured remote as well.

Add the helper function __git_is_configured_remote() that checks
whether its argument matches the name of a configured remote. Use
this helper to decide how to handle the remote passed to __git_refs().

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: respect 'git --git-dir=<path>' when listing remote refs

In __git_refs() the git commands listing refs, both short and full,
from a given remote repository are run without giving them the path to
the git repository which might have been specified on the command line
via 'git --git-dir=<path>'. This is bad, those git commands should
access the 'refs/remotes/<remote>/' hierarchy or the remote and
credentials configuration in that specified repository.

Use the __gitdir() helper only to find the path to the .git directory
and pass the resulting path to the 'git ls-remote' and 'for-each-ref'
executions that list remote refs. While modifying that 'for-each-ref'
line, remove the superfluous disambiguating doubledash.

Don't use __gitdir() to check that the given remote is on the file
system: basically it performs only a single if statement for us at the
considerable cost of fork()ing a subshell for a command substitution.
We are better off to perform all the necessary checks of the remote in
__git_refs().

Though __git_refs() was the last remaining callsite that passed a
remote to __gitdir(), don't delete __gitdir()'s remote-handling part
yet, just in case some users' custom completion scriptlets depend on
it.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: fix most spots not respecting 'git --git-dir=<path>'

The completion script already respects the path to the repository
specified on the command line most of the time, here we add the
necessary '--git-dir=$(__gitdir)' options to most of the places where
git was executed without it. The exceptions where said option is not
added are the git invocations:

- in __git_refs() which are non-trivial and will be the subject of
the following patch,

- getting the list of git commands, merge strategies and archive
formats, because these are independent from the repository and
thus don't need it, and

- the 'git rev-parse --git-dir' in __gitdir() itself.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: ensure that the repository path given on the command line exists

The __gitdir() helper function prints the path to the git repository
to its stdout or stays silent and returns with error when it can't
find a repository or when the repository given via $GIT_DIR doesn't
exist.

This is not the case, however, when the path in $__git_dir, i.e. the
path to the repository specified on the command line via 'git
--git-dir=<path>', doesn't exist: __gitdir() still outputs it as if it
were a real existing repository, making some completion functions
believe that they operate on an existing repository.

Check that the path in $__git_dir exists and return with error without
printing anything to stdout if it doesn't.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion tests: add tests for the __git_refs() helper function

Check how __git_refs() lists refs in different scenarios, i.e.

- short and full refs,
- from a local or from a remote repository,
- remote specified via path, name or URL,
- with or without a repository specified on the command line,
- non-existing remote,
- unique remote branches for 'git checkout's tracking DWIMery,
- not in a git repository, and
- interesting combinations of the above.

Seven of these tests expect failure, mostly demonstrating bugs related
to listing refs from a remote repository:

- ignoring the repository specified on the command line (2 tests),
- listing refs from the wrong place when the name of a configured
remote happens to match a directory,
- listing only 'HEAD' but no short refs from a remote given as URL,
- listing 'HEAD' even from non-existing remotes (2 tests), and
- listing 'HEAD' when not in a repository.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion tests: check __gitdir()'s output in the error cases

The __gitdir() helper function shouldn't output anything if not in a
git repository. The relevant tests only checked its error code, so
extend them to ensure that there's no output.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion tests: consolidate getting path of current working directory

Some tests of the __gitdir() helper function use the $TRASH_DIRECTORY
variable in direct path comparisons. In general this should be
avoided, because it might contain symbolic links. There happens to be
no issues with this here, however, because those tests use
$TRASH_DIRECTORY both for specifying the expected result and for
specifying input which in turn is just 'echo'ed verbatim.

Other __gitdir() tests ask for the path of the trash directory by
running $(pwd -P) in each test, sometimes even twice in a single test.

Run $(pwd) only once at the beginning of the test script to store the
path of the trash directory in a variable, and use that variable in
all __gitdir() tests.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion tests: make the $cur variable local to the test helper functions

The test helper functions test_gitcomp() and test_gitcomp_nl() leak
the $cur variable into the test environment. Since this variable has
a special role in the Bash completion script (it holds the word
currently being completed) it influences the behavior of most
completion functions and thus this leakage could interfere with
subsequent tests. Although there are no such issues in the current
tests, early versions of the new tests that will be added later in
this series suffered because of this.

It's better to play safe and declare $cur local in those test helper
functions. 'local' is bashism, of course, but the tests of the Bash
completion script are run under Bash anyway, and there are already
other variables declared local in this test script.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion tests: don't add test cruft to the test repository

While preparing commits, three tests added newly created files to the
index using 'git add .', which added not only the files in question
but leftover test cruft from previous tests like the files 'expected'
and 'actual' as well. Luckily, this had no effect on the tests'
correctness.

Add only the files we are actually interested in.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: improve __git_refs()'s in-code documentation

That "first argument is passed to __gitdir()" statement in particular
is not really helpful, and after this series it won't be the case
anyway.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Git 2.12-rc0

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Merge branch 'cw/log-updates-for-all-refs-really'

The "core.logAllRefUpdates" that used to be boolean has been
enhanced to take 'always' as well, to record ref updates to refs
other than the ones that are expected to be updated (i.e. branches,
remote-tracking branches and notes).

* cw/log-updates-for-all-refs-really:
doc: add note about ignoring '--no-create-reflog'
update-ref: add test cases for bare repository
refs: add option core.logAllRefUpdates = always
config: add markup to core.logAllRefUpdates doc

Merge branch 'pl/complete-diff-submodule-diff'

The command line completion (in contrib/) learned that
"git diff --submodule=" can take "diff" as a recently added option.

* pl/complete-diff-submodule-diff:
Completion: Add support for --submodule=diff

Merge branch 'rs/object-id'

"uchar [40]" to "struct object_id" conversion continues.

* rs/object-id:
checkout: convert post_checkout_hook() to struct object_id
use oidcpy() for copying hashes between instances of struct object_id
use oid_to_hex_r() for converting struct object_id hashes to hex strings

Merge branch 'js/re-running-failed-tests'

"make -C t failed" will now run only the tests that failed in the
previous run. This is usable only when prove is not use, and gives
a useless error message when run after "make clean", but otherwise
is serviceable.

* js/re-running-failed-tests:
t/Makefile: add a rule to re-run previously-failed tests

Merge branch 'sb/submodule-update-initial-runs-custom-script'

The user can specify a custom update method that is run when
"submodule update" updates an already checked out submodule. This
was ignored when checking the submodule out for the first time and
we instead always just checked out the commit that is bound to the
path in the superproject's index.

* sb/submodule-update-initial-runs-custom-script:
submodule update: run custom update script for initial populating as well

Merge branch 'sb/submodule-recursive-absorb'

When a submodule "A", which has another submodule "B" nested within
it, is "absorbed" into the top-level superproject, the inner
submodule "B" used to be left in a strange state. The logic to
adjust the .git pointers in these submodules has been corrected.

* sb/submodule-recursive-absorb:
submodule absorbing: fix worktree/gitdir pointers recursively for non-moves
cache.h: expose the dying procedure for reading gitlinks
setup: add gentle version of resolve_git_dir

Merge branch 'sb/unpack-trees-super-prefix'

"git read-tree" and its underlying unpack_trees() machinery learned
to report problematic paths prefixed with the --super-prefix option.

* sb/unpack-trees-super-prefix:
unpack-trees: support super-prefix option
t1001: modernize style
t1000: modernize style
read-tree: use OPT_BOOL instead of OPT_SET_INT

Sync with v2.11.1

* maint:
Git 2.11.1

Ninth batch for 2.12; almost ready for -rc0

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Merge branch 'nd/log-graph-configurable-colors'

Some people feel the default set of colors used by "git log --graph"
rather limiting. A mechanism to customize the set of colors has
been introduced.

* nd/log-graph-configurable-colors:
document behavior of empty color name
color_parse_mem: allow empty color spec
log --graph: customize the graph lines with config log.graphColors
color.c: trim leading spaces in color_parse_mem()
color.c: fix color_parse_mem() with value_len == 0

Merge branch 'ep/commit-static-buf-cleanup'

Code clean-up.

* ep/commit-static-buf-cleanup:
builtin/commit.c: switch to strbuf, instead of snprintf()
builtin/commit.c: remove the PATH_MAX limitation via dynamic allocation

Merge branch 'bc/use-asciidoctor-opt'

Asciidoctor, an alternative reimplementation of AsciiDoc, still
needs some changes to work with documents meant to be formatted
with AsciiDoc. "make USE_ASCIIDOCTOR=YesPlease" to use it out of
the box to document our pages is getting closer to reality.

* bc/use-asciidoctor-opt:
Documentation: implement linkgit macro for Asciidoctor
Makefile: add a knob to enable the use of Asciidoctor
Documentation: move dblatex arguments into variable
Documentation: add XSLT to fix DocBook for Texinfo
Documentation: sort sources for gitman.texi
Documentation: remove unneeded argument in cat-texi.perl
Documentation: modernize cat-texi.perl
Documentation: fix warning in cat-texi.perl

Merge branch 'sg/mailmap-self'

* sg/mailmap-self:
.mailmap: update Gábor Szeder's email address

Merge branch 'js/mingw-hooks-with-exe-suffix'

Names of the various hook scripts must be spelled exactly, but on
Windows, an .exe binary must be named with .exe suffix; notice
$GIT_DIR/hooks/<hookname>.exe as a valid <hookname> hook.

* js/mingw-hooks-with-exe-suffix:
mingw: allow hooks to be .exe files

Merge branch 'rs/receive-pack-cleanup'

Code clean-up.

* rs/receive-pack-cleanup:
receive-pack: call string_list_clear() unconditionally

Merge branch 'mm/reset-facl-before-umask-test'

Test tweaks for those who have default ACL in their git source tree
that interfere with the umask test.

* mm/reset-facl-before-umask-test:
t0001: don't let a default ACL interfere with the umask test

Merge branch 'hv/mingw-help-is-executable'

"git help" enumerates executable files in $PATH; the implementation
of "is this file executable?" on Windows has been optimized.

* hv/mingw-help-is-executable:
help: improve is_executable() on Windows

Merge branch 'gv/mingw-p4-mapuser'

"git p4" did not work well with multiple git-p4.mapUser entries on
Windows.

* gv/mingw-p4-mapuser:
git-p4: fix git-p4.mapUser on Windows

Merge branch 'rs/absolute-pathdup'

Code cleanup.

* rs/absolute-pathdup:
use absolute_pathdup()
abspath: add absolute_pathdup()

Merge branch 'js/unzip-in-usr-bin-workaround'

Test tweak for FreeBSD where /usr/bin/unzip is unsuitable to run
our tests but /usr/local/bin/unzip is usable.

* js/unzip-in-usr-bin-workaround:
test-lib: on FreeBSD, look for unzip(1) in /usr/local/bin/

Merge branch 'cw/doc-sign-off'

Doc update.

* cw/doc-sign-off:
doc: clarify distinction between sign-off and pgp-signing

Merge branch 'js/status-pre-rebase-i'

After starting "git rebase -i", which first opens the user's editor
to edit the series of patches to apply, but before saving the
contents of that file, "git status" failed to show the current
state (i.e. you are in an interactive rebase session, but you have
applied no steps yet) correctly.

* js/status-pre-rebase-i:
status: be prepared for not-yet-started interactive rebase

Merge branch 'js/retire-relink'

Cruft removal.

* js/retire-relink:
relink: really remove the command
relink: retire the command

Merge branch 'sb/submodule-add-force'

"git submodule add" used to be confused and refused to add a
locally created repository; users can now use "--force" option
to add them.

* sb/submodule-add-force:
submodule add: extend force flag to add existing repos

Git 2.11.1

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Merge branch 'ws/request-pull-code-cleanup' into maint

Code clean-up.

* ws/request-pull-code-cleanup:
request-pull: drop old USAGE stuff

Merge branch 'jk/execv-dashed-external' into maint

Typing ^C to pager, which usually does not kill it, killed Git and
took the pager down as a collateral damage in certain process-tree
structure. This has been fixed.

* jk/execv-dashed-external:
execv_dashed_external: wait for child on signal death
execv_dashed_external: stop exiting with negative code
execv_dashed_external: use child_process struct

document behavior of empty color name

Commit 55cccf4bb (color_parse_mem: allow empty color spec,
2017-02-01) clearly defined the behavior of an empty color
config variable. Let's document that, and give a hint about
why it might be useful.

It's important not to say that it makes the item uncolored,
because it doesn't. It just sets no attributes, which means
that any previous attributes continue to take effect.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

doc: add note about ignoring '--no-create-reflog'

The commands git-branch and git-tag accept the '--create-reflog'
option, and create reflog even when core.logallrefupdates
configuration is explicitly set not to.

On the other hand, the negated form '--no-create-reflog' is accepted
as a valid option but has no effect (other than overriding an
earlier '--create-reflog' on the command line). This silent noop may
puzzle users. To communicate that this is a known limitation, add a
short note in the manuals for git-branch and git-tag.

Signed-off-by: Cornelius Weig <cornelius.weig@tngtech.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

color_parse_mem: allow empty color spec

Prior to c2f41bf52 (color.c: fix color_parse_mem() with
value_len == 0, 2017-01-19), the empty string was
interpreted as a color "reset". This was an accidental
outcome, and that commit turned it into an error.

However, scripts may pass the empty string as a default
value to "git config --get-color" to disable color when the
value is not defined. The git-add--interactive script does
this. As a result, the script is unusable since c2f41bf52
unless you have color.diff.plain defined (if it is defined,
then we don't parse the empty default at all).

Our test scripts didn't notice the recent breakage because
they run without a terminal, and thus without color. They
never hit this code path at all. And nobody noticed the
original buggy "reset" behavior, because it was effectively
a noop.

Let's fix the code to have an empty color name produce an
empty sequence of color codes. The tests need a few fixups:

- we'll add a new test in t4026 to cover this case. But
note that we need to tweak the color() helper. While
we're there, let's factor out the literal ANSI ESC
character. Otherwise it makes the diff quite hard to
read.

- we'll add a basic sanity-check in t4026 that "git add
-p" works at all when color is enabled. That would have
caught this bug, as well as any others that are specific
to the color code paths.

- 73c727d69 (log --graph: customize the graph lines with
config log.graphColors, 2017-01-19) added a test to
t4202 that checks some "invalid" graph color config.
Since ",, blue" before yielded only "blue" as valid, and
now yields "empty, empty, blue", we don't match the
expected output.

One way to fix this would be to change the expectation
to the empty color strings. But that makes the test much
less interesting, since we show only two graph lines,
both of which would be colorless.

Since the empty-string case is now covered by t4026,
let's remove them entirely here. They're just in the way
of the primary thing the test is supposed to be
checking.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

.mailmap: update Gábor Szeder's email address

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Sync with maint

* maint:
Ready for 2.11.1

Ready for 2.11.1

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Merge branch 'sb/in-core-index-doc' into maint

Documentation and in-code comments updates.

* sb/in-core-index-doc:
documentation: retire unfinished documentation
cache.h: document add_[file_]to_index
cache.h: document remove_index_entry_at
cache.h: document index_name_pos

Merge branch 'js/mingw-isatty' into maint

An update to a topic that is already in 'master'.

* js/mingw-isatty:
mingw: follow-up to "replace isatty() hack"

Merge branch 'jk/coding-guidelines-update' into maint

Developer doc update.

* jk/coding-guidelines-update:
CodingGuidelines: clarify multi-line brace style

Merge branch 'js/exec-path-coverity-workaround' into maint

Code cleanup.

* js/exec-path-coverity-workaround:
git_exec_path: do not return the result of getenv()
git_exec_path: avoid Coverity warning about unfree()d result

Merge branch 'ad/bisect-terms' into maint

Documentation fix.

* ad/bisect-terms:
Documentation/bisect: improve on (bad|new) and (good|bad)

Merge branch 'jk/grep-e-could-be-extended-beyond-posix' into maint

Tighten a test to avoid mistaking an extended ERE regexp engine as
a PRE regexp engine.

* jk/grep-e-could-be-extended-beyond-posix:
t7810: avoid assumption about invalid regex syntax

Merge branch 'km/branch-get-push-while-detached' into maint

"git <cmd> @{push}" on a detached HEAD used to segfault; it has
been corrected to error out with a message.

* km/branch-get-push-while-detached:
branch_get_push: do not segfault when HEAD is detached

Merge branch 'jk/rebase-i-squash-count-fix' into maint

"git rebase -i" with a recent update started showing an incorrect
count when squashing more than 10 commits.

* jk/rebase-i-squash-count-fix:
rebase--interactive: count squash commits above 10 correctly

Merge branch 'jk/blame-fixes' into maint

"git blame --porcelain" misidentified the "previous" <commit, path>
pair (aka "source") when contents came from two or more files.

* jk/blame-fixes:
blame: output porcelain "previous" header for each file
blame: handle --no-abbrev
blame: fix alignment with --abbrev=40

Merge branch 'jk/archive-zip-userdiff-config' into maint

"git archive" did not read the standard configuration files, and
failed to notice a file that is marked as binary via the userdiff
driver configuration.

* jk/archive-zip-userdiff-config:
archive-zip: load userdiff config

Merge branch 'dt/disable-bitmap-in-auto-gc' into maint

It is natural that "git gc --auto" may not attempt to pack
everything into a single pack, and there is no point in warning
when the user has configured the system to use the pack bitmap,
leading to disabling further "gc".

* dt/disable-bitmap-in-auto-gc:
repack: die on incremental + write-bitmap-index
auto gc: don't write bitmaps for incremental repacks

Merge branch 'nd/config-misc-fixes' into maint

Leakage of lockfiles in the config subsystem has been fixed.

* nd/config-misc-fixes:
config.c: handle lock file in error case in git_config_rename_...
config.c: rename label unlock_and_out
config.c: handle error case for fstat() calls

Merge branch 'jc/abbrev-autoscale-config' into maint

Recent update to the default abbreviation length that auto-scales
lacked documentation update, which has been corrected.

* jc/abbrev-autoscale-config:
config.abbrev: document the new default that auto-scales

Merge branch 'mh/fast-import-notes-fix-new' into maint

"git fast-import" sometimes mishandled while rebalancing notes
tree, which has been fixed.

* mh/fast-import-notes-fix-new:
fast-import: properly fanout notes when tree is imported

Merge branch 'jc/compression-config' into maint

Compression setting for producing packfiles were spread across
three codepaths, one of which did not honor any configuration.
Unify these so that all of them honor core.compression and
pack.compression variables the same way.

* jc/compression-config:
compression: unify pack.compression configuration parsing

Merge branch 'ew/svn-fixes' into maint

Meant eventually for 'maint'.

* ew/svn-fixes:
git-svn: document useLogAuthor and addAuthorFrom config keys
git-svn: allow "0" in SVN path components

Merge branch 'ls/travis-p4-on-macos' into maint

Update the definition of the MacOSX test environment used by
TravisCI.

* ls/travis-p4-on-macos:
travis-ci: fix Perforce install on macOS

Merge branch 'jk/make-tags-find-sources-tweak' into maint

Update the procedure to generate "tags" for developer support.

* jk/make-tags-find-sources-tweak:
Makefile: exclude contrib from FIND_SOURCE_FILES
Makefile: match shell scripts in FIND_SOURCE_FILES
Makefile: exclude test cruft from FIND_SOURCE_FILES
Makefile: reformat FIND_SOURCE_FILES

Merge branch 'jc/latin-1' into maint

Some platforms no longer understand "latin-1" that is still seen in
the wild in e-mail headers; replace them with "iso-8859-1" that is
more widely known when conversion fails from/to it.

* jc/latin-1:
utf8: accept "latin-1" as ISO-8859-1
utf8: refactor code to decide fallback encoding

Eighth batch for 2.12

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Merge branch 'jk/fsck-connectivity-check-fix'

"git fsck --connectivity-check" was not working at all.

* jk/fsck-connectivity-check-fix:
fsck: lazily load types under --connectivity-only
fsck: move typename() printing to its own function
t1450: use "mv -f" within loose object directory
fsck: check HAS_OBJ more consistently
fsck: do not fallback "git fsck <bogus>" to "git fsck"
fsck: tighten error-checks of "git fsck <head>"
fsck: prepare dummy objects for --connectivity-check
fsck: report trees as dangling
t1450: clean up sub-objects in duplicate-entry test

Merge branch 'js/difftool-builtin'

Rewrite a scripted porcelain "git difftool" in C.

* js/difftool-builtin:
difftool: hack around -Wzero-length-format warning
difftool: retire the scripted version
difftool: implement the functionality in the builtin
difftool: add a skeleton for the upcoming builtin

Merge branch 'rs/qsort-s'

A few codepaths had to rely on a global variable when sorting
elements of an array because sort(3) API does not allow extra data
to be passed to the comparison function. Use qsort_s() when
natively available, and a fallback implementation of it when not,
to eliminate the need, which is a prerequisite for making the
codepath reentrant.

* rs/qsort-s:
ref-filter: use QSORT_S in ref_array_sort()
string-list: use QSORT_S in string_list_sort()
perf: add basic sort performance test
add QSORT_S
compat: add qsort_s()

Merge branch 'ls/travis-p4-on-macos'

Update the definition of the MacOSX test environment used by
TravisCI.

* ls/travis-p4-on-macos:
travis-ci: fix Perforce install on macOS

Merge branch 'vp/show-ref-verify-head'

"git show-ref HEAD" used with "--verify" because the user is not
interested in seeing refs/remotes/origin/HEAD, and used with
"--head" because the user does not want HEAD to be filtered out,
i.e. "git show-ref --head --verify HEAD", did not work as expected.

* vp/show-ref-verify-head:
show-ref: remove a stale comment
show-ref: remove dead `if (verify)' check
show-ref: detect dangling refs under --verify as well
show-ref: move --quiet handling into show_one()
show-ref: allow -d to work with --verify
show-ref: accept HEAD with --verify

Merge branch 'sb/retire-convert-objects-from-contrib'

Remove an ancient tool left in contrib/.

* sb/retire-convert-objects-from-contrib:
contrib: remove git-convert-objects

Merge branch 'sb/in-core-index-doc'

Documentation and in-code comments updates.

* sb/in-core-index-doc:
documentation: retire unfinished documentation
cache.h: document add_[file_]to_index
cache.h: document remove_index_entry_at
cache.h: document index_name_pos