fix clang -Wtautological-compare with unsigned enum

Create a GREP_HEADER_FIELD_MIN so we can check that the field value is
sane and silence the clang warning.

Clang warning happens because the enum is unsigned (this is
implementation-defined, and there is no negative fields) and the check
is then tautological.

Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: John Keeping <john@keeping.me.uk>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Allow combined diff to ignore white-spaces

The combined diff --cc output does not honor options to ignore
whitespace changes (-b, -w, and --ignore-space-at-eol).

Correct this by passing diff flags to diff engine, so that combined
diff behaves as normal diff does with spaces, and by coalescing
lines that are removed from both (or more) parents, honoring the
same rule to ignore whitespace changes.

With this change, a conflict-less merge done using a ignore-*
strategy option will not show any conflict if shown in combined-diff
using the same option.

Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pull: Apply -q and -v options to rebase mode as well

git pull passed -q and -v only to git merge, but they can be useful for
git rebase as well, so pass them there, too.

In particular, using -q shuts up the "Already up-to-date." message.
Especially, a new test script runs the same "pull --rebase" twice to
make sure both cases are quiet, when it has something to fetch and
when it is already up to date.

Signed-off-by: Peter Eisentraut <peter@eisentraut.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge: a random object may not necssarily be a commit

The user could have said "git merge $(git rev-parse v1.0.0)"; we
shouldn't mark it as "Merge commit '15999998fb...'" as the merge
name, even though such an invocation might be crazy.

We could even read the "tag " header from the tag object and replace
the object name the user gave us, but let's not lose the information
by doing so, at least not yet.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t3200 (branch): modernize style

Style is inconsistent throughout the file.  Make the following
changes:

1. Indent everything with tabs.

2. Put the opening quote (') for the test in the same line as
   test_expect_success, and the closing quote on a line by itself.

3. Do not add extra space between redirection operator and filename,
   i.e. "cmd >dst", not "cmd > dst".

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply --whitespace=fix: avoid running over the postimage buffer

Originally update-pre-post-images could assume that any whitespace
fixing will make the result only shorter by unexpanding runs of
leading SPs into HTs and removing trailing whitespaces at the end of
lines.  Updating the post-image we read from the patch to match the
actual result can be performed in-place under this assumption.
These days, however, we have tab-in-indent (aka Python) rule whose
result can be longer than the original, and we do need to allocate
a larger buffer than the input and replace the result.

Fortunately the support for lengthening rewrite was already added
when we began supporting "match while ignoring whitespace
differences" mode in 86c91f91794c (git apply: option to ignore
whitespace differences, 2009-08-04).  We only need to correctly
count the number of bytes necessary to hold the updated result and
tell the function to allocate a new buffer.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
submodule: clarify logic in show_submodule_summary

There are two uses of the "left" and "right" commit variables that
make it hard to be sure what values they have (both for the reader,
and for gcc, which wrongly complains that they might be used
uninitialized).

The function starts with a cascading if statement, checking that the
input sha1s exist, and finally working up to preparing a revision
walk. We only prepare the walk if the cascading conditional did not
find any problems, which we check by seeing whether it set the
"message" variable or not. It's simpler and more obvious to just add
a condition to the end of the cascade.

Later, we check the same "message" variable when deciding whether to
clear commit marks on the left/right commits; if it is set, we
presumably never started the walk. This is wrong, though; we might
have started the walk and munged commit flags, only to encounter an
error afterwards. We should always clear the flags on left/right if
they exist, whether the walk was successful or not.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
match-trees: simplify score_trees() using tree_entry()

Convert the loop in score_trees() to tree_entry().  The code becomes
shorter and simpler because the calls to update_tree_entry() are not
needed any more.

Another benefit is that we need less variables to track the current
tree entries; as a side-effect of that the compiler has an easier
job figuring out the control flow and thus can avoid false warnings
about uninitialized variables.

Using struct name_entry also allows the use of tree_entry_len() for
finding the path length instead of strlen(), which may be slightly
more efficient.

Also unify the handling of missing entries in one of the two trees
(i.e. added or removed files): Just set cmp appropriately first, no
matter if we ran off the end of a tree or if we actually have two
entries to compare, and check its value a bit later without
duplicating the handler code.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5516: test interaction between pushURL and pushInsteadOf correctly

1c2eafb89bca (Add url.<base>.pushInsteadOf: URL rewriting for push
only, 2009-09-07) wants to make sure that a push destination read
from URL is not rewritten by pushInsteadOf because an explicit
pushURL exists; for that, a pushInsteadOf rewrite rule for the value
of remote.r.URL is set to a non-existent is set up.

We would also want to make sure that pushInsteadOf rewrite rule is
not applied to the location read from pushURL.

This way, we will make sure that

 - "testrepo/" (pushURL) gets updated;

 - the push does not try to update "trash2/" (the result of applying
   pushInsteadOf to pushURL);

 - the push does not try to update "trash3/" (the result of applying
   pushInsteadOf to URL).

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

New test may want to use this helper; keep it for them that do not
need to protect literal SP.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
bash: teach __git_ps1 about REVERT_HEAD

Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
send-email: use "return;" not "return undef;" on error codepaths

All the callers of "ask", "extract_valid_address", and "validate_patch"
subroutines assign the return values from them to a single scalar:

	$var = subr(...);

and "return undef;" in these subroutine can safely be turned into a
simpler "return;".  Doing so will also future-proof a new caller that
mistakenly does this:

    @foo = ask(...);
    if (@foo) { ... we got an answer ... } else { ... we did not ... }

Note that we leave "return undef;" in validate_address on purpose,
even though Perlcritic may complain.  The primary "return" site of
the function returns whatever is in the scalar variable $address, so
it is pointless to change only the other "return undef;" to "return".
The caller must be prepared to see an array with a single undef as
the return value from this subroutine anyway.

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
send-email: drop misleading function prototype

The subroutine check_file_rev_conflict() is called from two places,
both of which expects to pass a single scalar variable and see if
that can be interpreted as a pathname or a revision name.  It is
defined with a function prototype ($) to force a scalar context
while evaluating the arguments at the calling site but it does not
help the current calling sites.  The only effect it has is to hurt
future calling sites that may want to build an argument list in an
array variable and call it as check_file_rev_confict(@args).

Drop the misleading prototype, as Perlcritic suggests.

While at it, rename the function to avoid new call sites unaware of
this change arising and add a comment clarifying what this function
is for.

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
send-email: use the three-arg form of open in recipients_cmd

Perlcritic does not want to see the trailing pipe in the two-args
form of open(), i.e.

	open my $fh, "$cmd \Q$file\E |";

If $cmd were a single-token command name, it would make a lot more
sense to use four-or-more-args form "open FILEHANDLE,MODE,CMD,ARGS"
to avoid shell from expanding metacharacters in $file, but we do
expect multi-word string in $to_cmd and $cc_cmd to be expanded by
the shell, so we cannot rewrite it to

	open my $fh, "-|", $cmd, $file;

for extra safety.  At least, by using this in the three-arg form:

	open my $fh, "-|", "$cmd \Q$file\E";

we can silence Perlcritic, even though we do not gain much safety by
doing so.

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t6200: use test_config/test_unconfig

The tests were already well protected from previous ones by running
"git config --unset" on variables early they do not want to see, but
it is easier to make sure they start from a clean state by using
more modern test_config/test_unconfig helper functions.

It turns out that the last test depended on the merge.summary
configuration previous one leaves behind.  Set it explicitly in it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t6200: test message for merging of an annotated tag

Signed-off-by: Junio C Hamano <gitster@pobox.com>
rerere forget: grok files containing NUL

Using 'git rerere forget .' after a merge that involved binary files
runs into an infinite loop if the binary file contains a zero byte.
Replace a strchrnul by memchr because the former does not make progress
as soon as the NUL is encountered.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
filter-branch: return to original dir after filtering

The first thing filter-branch does is to create a temporary
directory, either ".git-rewrite" in the current directory
(which may be the working tree or the repository if bare),
or in a directory specified by "-d". We then chdir to
$tempdir/t as our temporary working directory in which to run
tree filters.

After finishing the filter, we then attempt to go back to
the original directory with "cd ../..". This works in the
.git-rewrite case, but if "-d" is used, we end up in a
random directory. The only thing we do after this chdir is
to run git-read-tree, but that means that:

  1. The working directory is not updated to reflect the
     filtered history.

  2. We dump random files into "$tempdir/.." (e.g., if you
     use "-d /tmp/foo", we dump junk into /tmp).

Fix it by recording the full path to the original directory
and returning there explicitly.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diffcore-break: don't divide by zero

When the source file is empty, the calculation of the merge score
results in a division by zero.  In the situation:

     == preimage ==             == postimage ==

     F (empty file)             F (a large file)
                                E (a new empty file)

it does not make sense to consider F->E as a rename, so it is better not
to break the pre- and post-image of F.

Bail out early in this case to avoid hitting the divide-by-zero.  This
causes the merge score to be left at zero.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
bisect: avoid signed integer overflow

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>