Commits 2122f8b9 ("rev-parse: Add support for the ^! and ^@ syntax",
2008-07-26) and 3dd4e732 ("Teach rev-parse the ... syntax.", 2006-07-04)
taught rev-parse new syntax, and used lookup_commit_reference() as part of
their logic.  Neither usage checked the returned commit to see if it was
non-NULL before using it.  Check for NULL and ensure an appropriate error
is reported to the user.

Reported by Florian Weimer and Todd Zullinger.
Helped-by: NJeff King <peff@peff.net>
Signed-off-by: NElijah Newren <newren@gmail.com>
Reviewed-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The try_parent_shorthands() function shows each parent via
show_rev(). We pass the correct parent sha1, but our "name"
parameter still points at the original refname. So asking
for a regular rev-parse works fine (it prints the sha1s),
but asking for the symbolic name gives nonsense like:

    $ git rev-parse --symbolic HEAD^-1
    HEAD
    ^HEAD

which is always an empty set of commits. Asking for "^!" is
likewise broken, with the added bonus that its prints ^HEAD
for _each_ parent. And "^@" just prints HEAD repeatedly.

Arguably it would be correct to just pass NULL as the name
here, and always get the parent expressed as a sha1. The
"--symbolic" documentaton claims only "as close to the
original input as possible", and we certainly fallback to
sha1s where necessary. But it's pretty easy to generate a
symbolic name on the fly from the original.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

"git log rev^..rev" is commonly used to show all work done on and merged
from a side branch. This patch introduces a shorthand "rev^-" for this
and additionally allows "rev^-$n" to mean "reachable from rev, excluding
what is reachable from the nth parent of rev". For example, for a
two-parent merge, you can use rev^-2 to get the set of commits which were
made to the main branch while the topic branch was prepared.
Signed-off-by: NVegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

While it makes sense to allow merging unrelated histories of two
projects that started independently into one, in the way "gitk" was
merged to "git" itself aka "the coolest merge ever", such a merge is
still an unusual event.	 Worse, if somebody creates an independent
history by starting from a tarball of an established project and
sends a pull request to the original project, "git merge" however
happily creates such a merge without any sign of something unusual
is happening.

Teach "git merge" to refuse to create such a merge by default,
unless the user passes a new "--allow-unrelated-histories" option to
tell it that the user is aware that two unrelated projects are
merged.

Because such a "two project merge" is a rare event, a configuration
option to always allow such a merge is not added.

We could add the same option to "git pull" and have it passed
through to underlying "git merge".  I do not have a fundamental
opposition against such a feature, but this commit does not do so
and instead leaves it as low-hanging fruit for others, because such
a "two project merge" would be done after fetching the other project
into some location in the working tree of an existing project and
making sure how well they fit together, it is sufficient to allow a
local merge without such an option pass-through from "git pull" to
"git merge".  Many tests that are updated by this patch does the
pass-through manually by turning:

	git pull something

into its equivalent:

	git fetch something &&
	git merge --allow-unrelated-histories FETCH_HEAD

If somebody is inclined to add such an option, updated tests in this
change need to be adjusted back to:

	git pull --allow-unrelated-histories something
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Support for grafts predates Git's strbuf, and hence it is understandable
that there was a hard-coded line length limit of 1023 characters (which
was chosen a bit awkwardly, given that it is *exactly* one byte short of
aligning with the 41 bytes occupied by a commit name and the following
space or new-line character).

While regular commit histories hardly win comprehensibility in general
if they merge more than twenty-two branches in one go, it is not Git's
business to limit grafts in such a way.

In this particular developer's case, the use case that requires
substantially longer graft lines to be supported is the visualization of
the commits' order implied by their changes: commits are considered to
have an implicit relationship iff exchanging them in an interactive
rebase would result in merge conflicts.

Thusly implied branches tend to be very shallow in general, and the
resulting thicket of implied branches is usually very wide; It is
actually quite common that *most* of the commits in a topic branch have
not even one implied parent, so that a final merge commit has about as
many implied parents as there are commits in said branch.

[jc: squashed in tests by Jonathan]
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Save the reader from learning specialized t6* setup functions
where familiar commands like test_commit, "git checkout --orphan",
and "git merge" will do.

While at it, wrap the setup commands in a test assertion so errors can
be caught and stray output suppressed when running without --verbose
as in other tests.
Signed-off-by: NFelipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Use test_cmp instead of passing two command substitutions to the
"test" builtin.  This way:

 - when tests fail, they can print a helpful diff if run with
   "--verbose"

 - the argument order "test_cmp expect actual" feels natural,
   unlike test <known> = <unknown> that seems backwards

 - the exit status from invoking git is checked, so if rev-parse
   starts segfaulting then the test will notice and fail

Use a custom function for this instead of test_cmp_rev to emphasize
that we are testing the output from "git rev-parse" with certain
arguments, not checking that the revisions are equal in abstract.
Reported-by: NFelipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This way, if rev-parse segfaults then the test will fail instead
of treating it the same way as a controlled failure.
Signed-off-by: NFelipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Instead of cramming everything in one line, put the test body in an
indented block after the opening test_expect_success line and quote
and put the closing quote on a line by itself.

Use single-quote instead of double-quote to quote the test body
for more useful --verbose output.
Signed-off-by: NFelipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The naming of this test library conflicted with the recommendation in
t/README's "Naming Tests" section.
Signed-off-by: NÆvar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Many test scripts assumed that they will start in a 'trash' subdirectory
that is a single level down from the t/ directory, and referred to their
test vector files by asking for files like "../t9999/expect".  This will
break if we move the 'trash' subdirectory elsewhere.

To solve this, we earlier introduced "$TEST_DIRECTORY" so that they can
refer to t/ directory reliably.  This finally makes all the tests use
it to refer to the outside environment.

With this patch, and a one-liner not included here (because it would
contradict with what Dscho really wants to do):

| diff --git a/t/test-lib.sh b/t/test-lib.sh
| index 70ea7e0..60e69e4 100644
| --- a/t/test-lib.sh
| +++ b/t/test-lib.sh
| @@ -485,7 +485,7 @@ fi
|  . ../GIT-BUILD-OPTIONS
|
|  # Test repository
| -test="trash directory"
| +test="trash directory/another level/yet another"
|  rm -fr "$test" || {
|         trap - exit
|         echo >&5 "FATAL: Cannot prepare test area"

all the tests still pass, but we would want extra sets of eyeballs on this
type of change to really make sure.

[jc: with help from Stephan Beyer on http-push tests I do not run myself;
 credits for locating silly quoting errors go to Olivier Marin.]
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Those shorthands are explained in the rev-parse documentation but were not
actually supported by rev-parse itself.

gitk internally uses rev-parse to interpret its command line arguments, and
being able to use these "limit with parents" syntax is handy there.
Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This patch changes every occurrence of "! git" -- with the meaning
that a git call has to gracefully fail -- into "test_must_fail git".

This is useful to

 - make sure the test does not fail because of a signal,
   e.g. SIGSEGV, and

 - advertise the use of "test_must_fail" for new tests.
Signed-off-by: NStephan Beyer <s-beyer@gmx.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Originally, test_expect_failure was designed to be the opposite
of test_expect_success, but this was a bad decision.  Most tests
run a series of commands that leads to the single command that
needs to be tested, like this:

    test_expect_{success,failure} 'test title' '
	setup1 &&
        setup2 &&
        setup3 &&
        what is to be tested
    '

And expecting a failure exit from the whole sequence misses the
point of writing tests.  Your setup$N that are supposed to
succeed may have failed without even reaching what you are
trying to test.  The only valid use of test_expect_failure is to
check a trivial single command that is expected to fail, which
is a minority in tests of Porcelain-ish commands.

This large-ish patch rewrites all uses of test_expect_failure to
use test_expect_success and rewrites the condition of what is
tested, like this:

    test_expect_success 'test title' '
	setup1 &&
        setup2 &&
        setup3 &&
        ! this command should fail
    '

test_expect_failure is redefined to serve as a reminder that
that test *should* succeed but due to a known breakage in git it
currently does not pass.  So if git-foo command should create a
file 'bar' but you discovered a bug that it doesn't, you can
write a test like this:

    test_expect_failure 'git-foo should create bar' '
        rm -f bar &&
        git foo &&
        test -f bar
    '

This construct acts similar to test_expect_success, but instead
of reporting "ok/FAIL" like test_expect_success does, the
outcome is reported as "FIXED/still broken".
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This uses the remove-dashes target to replace "git-frotz" to "git frotz".
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time.  There are a few files that need
to have trailing whitespaces (most notably, test vectors).  The results
still passes the test, and build result in Documentation/ area is unchanged.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

My recent patch "Lazily open pack index files on demand" caused a
regression in the case of parsing abbreviated SHA-1 object names.
Git was unable to translate the abbreviated name into the full name
if the object was packed, as the pack .idx files were not opened
before being accessed.

This is a simple test to repack a repository then test for an
abbreviated SHA-1 within the packfile.
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NJunio C Hamano <junkio@cox.net>

just for consistency.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

As promised, this is the "big tool rename" patch.  The primary differences
since 0.99.6 are:

  (1) git-*-script are no more.  The commands installed do not
      have any such suffix so users do not have to remember if
      something is implemented as a shell script or not.

  (2) Many command names with 'cache' in them are renamed with
      'index' if that is what they mean.

There are backward compatibility symblic links so that you and
Porcelains can keep using the old names, but the backward
compatibility support  is expected to be removed in the near
future.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

git-rev-parse HEAD^1 would fail, because of an off-by-one bug (but HEAD^
would yield the expected result). Also, when the parent does not exist, do
not silently return an incorrect SHA1. Of course, this no longer applies
to git-rev-parse alone, but every user of get_sha1().

While at it, add a test.
Signed-off-by: NJohannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <junkio@cox.net>