Merge commit 'b319ef7' into jc/maint-fix-test-perm

* commit 'b319ef7': (8132 commits)
  Add a small patch-mode testing library
  git-apply--interactive: Refactor patch mode code
  t8005: Nobody writes Russian in shift_jis
  Fix severe breakage in "git-apply --whitespace=fix"
  Update release notes for 1.6.4
  After renaming a section, print any trailing variable definitions
  Make section_name_match start on '[', and return the length on success
  send-email: detect cycles in alias expansion
  Show the presence of untracked files in the bash prompt.
  SunOS grep does not understand -C<n> nor -e
  Fix export_marks() error handling.
  git repack: keep commits hidden by a graft
  Add a test showing that 'git repack' throws away grafted-away parents
  git branch: clean up detached branch handling
  git branch: avoid unnecessary object lookups
  git branch: fix performance problem
  git svn: fix shallow clone when upstream revision is too new
  do_one_ref(): null_sha1 check is not about broken ref
  configure.ac: properly unset NEEDS_SSL_WITH_CRYPTO when sha1 func is missing
  janitor: useless checks before free
  ...

1 files changed, 190 insertions, 69 deletions

diff --git a/Documentation/git-bisect.txt b/Documentation/git-bisect.txt
index 5f68ee1584..63e7a42cb3 100644
--- a/Documentation/git-bisect.txt
+++ b/Documentation/git-bisect.txt
@@ -3,35 +3,44 @@ git-bisect(1)
 
 NAME
 ----
-git-bisect - Find the change that introduced a bug by binary search
+git-bisect - Find by binary search the change that introduced a bug
 
 
 SYNOPSIS
 --------
-'git bisect' <subcommand> <options> 
+'git bisect' <subcommand> <options>
 
 DESCRIPTION
 -----------
 The command takes various subcommands, and different options depending
 on the subcommand:
 
+ git bisect help
  git bisect start [<bad> [<good>...]] [--] [<paths>...]
- git bisect bad <rev>
- git bisect good <rev>
+ git bisect bad [<rev>]
+ git bisect good [<rev>...]
+ git bisect skip [(<rev>|<range>)...]
  git bisect reset [<branch>]
  git bisect visualize
  git bisect replay <logfile>
  git bisect log
  git bisect run <cmd>...
 
-This command uses 'git-rev-list --bisect' option to help drive the
+This command uses 'git rev-list --bisect' to help drive the
 binary search process to find which change introduced a bug, given an
 old "good" commit object name and a later "bad" commit object name.
 
+Getting help
+~~~~~~~~~~~~
+
+Use "git bisect" to get a short usage description, and "git bisect
+help" or "git bisect -h" to get a long usage description.
+
 Basic bisect commands: start, bad, good
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-The way you use it is:
+Using the Linux kernel tree as an example, basic use of the bisect
+command is as follows:
 
 ------------------------------------------------
 $ git bisect start
@@ -40,115 +49,159 @@ $ git bisect good v2.6.13-rc2    # v2.6.13-rc2 was the last version
                                  # tested that was good
 ------------------------------------------------
 
-When you give at least one bad and one good versions, it will bisect
-the revision tree and say something like:
+When you have specified at least one bad and one good version, the
+command bisects the revision tree and outputs something similar to
+the following:
 
 ------------------------------------------------
 Bisecting: 675 revisions left to test after this
 ------------------------------------------------
 
-and check out the state in the middle. Now, compile that kernel, and
-boot it. Now, let's say that this booted kernel works fine, then just
-do
+The state in the middle of the set of revisions is then checked out.
+You would now compile that kernel and boot it. If the booted kernel
+works correctly, you would then issue the following command:
 
 ------------------------------------------------
 $ git bisect good			# this one is good
 ------------------------------------------------
 
-which will now say
+The output of this command would be something similar to the following:
 
 ------------------------------------------------
 Bisecting: 337 revisions left to test after this
 ------------------------------------------------
 
-and you continue along, compiling that one, testing it, and depending
-on whether it is good or bad, you say "git bisect good" or "git bisect
-bad", and ask for the next bisection.
+You keep repeating this process, compiling the tree, testing it, and
+depending on whether it is good or bad issuing the command "git bisect good"
+or "git bisect bad" to ask for the next bisection.
 
-Until you have no more left, and you'll have been left with the first
-bad kernel rev in "refs/bisect/bad".
+Eventually there will be no more revisions left to bisect, and you
+will have been left with the first bad kernel revision in "refs/bisect/bad".
 
 Bisect reset
 ~~~~~~~~~~~~
 
-Oh, and then after you want to reset to the original head, do a
+To return to the original head after a bisect session, issue the
+following command:
 
 ------------------------------------------------
 $ git bisect reset
 ------------------------------------------------
 
-to get back to the master branch, instead of being in one of the
-bisection branches ("git bisect start" will do that for you too,
-actually: it will reset the bisection state, and before it does that
-it checks that you're not using some old bisection branch).
+This resets the tree to the original branch instead of being on the
+bisection commit ("git bisect start" will also do that, as it resets
+the bisection state).
 
 Bisect visualize
 ~~~~~~~~~~~~~~~~
 
-During the bisection process, you can say
+To see the currently remaining suspects in 'gitk', issue the following
+command during the bisection process:
 
 ------------
 $ git bisect visualize
 ------------
 
-to see the currently remaining suspects in `gitk`.
+`view` may also be used as a synonym for `visualize`.
+
+If the 'DISPLAY' environment variable is not set, 'git log' is used
+instead.  You can also give command line options such as `-p` and
+`--stat`.
+
+------------
+$ git bisect view --stat
+------------
 
 Bisect log and bisect replay
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-The good/bad input is logged, and
+After having marked revisions as good or bad, issue the following
+command to show what has been done so far:
 
 ------------
 $ git bisect log
 ------------
 
-shows what you have done so far. You can truncate its output somewhere
-and save it in a file, and run
+If you discover that you made a mistake in specifying the status of a
+revision, you can save the output of this command to a file, edit it to
+remove the incorrect entries, and then issue the following commands to
+return to a corrected state:
 
 ------------
+$ git bisect reset
 $ git bisect replay that-file
 ------------
 
-if you find later you made a mistake telling good/bad about a
-revision.
-
-Avoiding to test a commit
+Avoiding testing a commit
 ~~~~~~~~~~~~~~~~~~~~~~~~~
 
-If in a middle of bisect session, you know what the bisect suggested
-to try next is not a good one to test (e.g. the change the commit
+If, in the middle of a bisect session, you know that the next suggested
+revision is not a good one to test (e.g. the change the commit
 introduces is known not to work in your environment and you know it
 does not have anything to do with the bug you are chasing), you may
-want to find a near-by commit and try that instead.
+want to find a nearby commit and try that instead.
 
-It goes something like this:
+For example:
 
 ------------
-$ git bisect good/bad			# previous round was good/bad.
+$ git bisect good/bad			# previous round was good or bad.
 Bisecting: 337 revisions left to test after this
 $ git bisect visualize			# oops, that is uninteresting.
-$ git reset --hard HEAD~3		# try 3 revs before what
+$ git reset --hard HEAD~3		# try 3 revisions before what
 					# was suggested
 ------------
 
-Then compile and test the one you chose to try. After that, tell
-bisect what the result was as usual.
+Then compile and test the chosen revision, and afterwards mark
+the revision as good or bad in the usual manner.
+
+Bisect skip
+~~~~~~~~~~~~
+
+Instead of choosing by yourself a nearby commit, you can ask git
+to do it for you by issuing the command:
+
+------------
+$ git bisect skip                 # Current version cannot be tested
+------------
+
+But git may eventually be unable to tell the first bad commit among
+a bad commit and one or more skipped commits.
+
+You can even skip a range of commits, instead of just one commit,
+using the "'<commit1>'..'<commit2>'" notation. For example:
+
+------------
+$ git bisect skip v2.5..v2.6
+------------
+
+This tells the bisect process that no commit after `v2.5`, up to and
+including `v2.6`, should be tested.
+
+Note that if you also want to skip the first commit of the range you
+would issue the command:
+
+------------
+$ git bisect skip v2.5 v2.5..v2.6
+------------
+
+This tells the bisect process that the commits between `v2.5` included
+and `v2.6` included should be skipped.
+
 
 Cutting down bisection by giving more parameters to bisect start
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-You can further cut down the number of trials if you know what part of
-the tree is involved in the problem you are tracking down, by giving
-paths parameters when you say `bisect start`, like this:
+You can further cut down the number of trials, if you know what part of
+the tree is involved in the problem you are tracking down, by specifying
+path parameters when issuing the `bisect start` command:
 
 ------------
 $ git bisect start -- arch/i386 include/asm-i386
 ------------
 
-If you know beforehand more than one good commits, you can narrow the
-bisect space down without doing the whole tree checkout every time you
-give good commits. You give the bad revision immediately after `start`
-and then you give all the good revisions you have:
+If you know beforehand more than one good commit, you can narrow the
+bisect space down by specifying all of the good commits immediately after
+the bad commit when issuing the `bisect start` command:
 
 ------------
 $ git bisect start v2.6.20-rc6 v2.6.20-rc4 v2.6.20-rc1 --
@@ -160,34 +213,103 @@ Bisect run
 ~~~~~~~~~~
 
 If you have a script that can tell if the current source code is good
-or bad, you can automatically bisect using:
+or bad, you can bisect by issuing the command:
 
 ------------
-$ git bisect run my_script
+$ git bisect run my_script arguments
 ------------
 
-Note that the "run" script (`my_script` in the above example) should
-exit with code 0 in case the current source code is good and with a
-code between 1 and 127 (included) in case the current source code is
-bad.
+Note that the script (`my_script` in the above example) should
+exit with code 0 if the current source code is good, and exit with a
+code between 1 and 127 (inclusive), except 125, if the current
+source code is bad.
+
+Any other exit code will abort the bisect process. It should be noted
+that a program that terminates via "exit(-1)" leaves $? = 255, (see the
+exit(3) manual page), as the value is chopped with "& 0377".
+
+The special exit code 125 should be used when the current source code
+cannot be tested. If the script exits with this code, the current
+revision will be skipped (see `git bisect skip` above).
+
+You may often find that during a bisect session you want to have
+temporary modifications (e.g. s/#define DEBUG 0/#define DEBUG 1/ in a
+header file, or "revision that does not have this commit needs this
+patch applied to work around another problem this bisection is not
+interested in") applied to the revision being tested.
+
+To cope with such a situation, after the inner 'git bisect' finds the
+next revision to test, the script can apply the patch
+before compiling, run the real test, and afterwards decide if the
+revision (possibly with the needed patch) passed the test and then
+rewind the tree to the pristine state.  Finally the script should exit
+with the status of the real test to let the "git bisect run" command loop
+determine the eventual outcome of the bisect session.
+
+EXAMPLES
+--------
 
-Any other exit code will abort the automatic bisect process. (A
-program that does "exit(-1)" leaves $? = 255, see exit(3) manual page,
-the value is chopped with "& 0377".)
+* Automatically bisect a broken build between v1.2 and HEAD:
++
+------------
+$ git bisect start HEAD v1.2 --      # HEAD is bad, v1.2 is good
+$ git bisect run make                # "make" builds the app
+------------
 
-You may often find that during bisect you want to have near-constant
-tweaks (e.g., s/#define DEBUG 0/#define DEBUG 1/ in a header file, or
-"revision that does not have this commit needs this patch applied to
-work around other problem this bisection is not interested in")
-applied to the revision being tested.
+* Automatically bisect a test failure between origin and HEAD:
++
+------------
+$ git bisect start HEAD origin --    # HEAD is bad, origin is good
+$ git bisect run make test           # "make test" builds and tests
+------------
 
-To cope with such a situation, after the inner git-bisect finds the
-next revision to test, with the "run" script, you can apply that tweak
-before compiling, run the real test, and after the test decides if the
-revision (possibly with the needed tweaks) passed the test, rewind the
-tree to the pristine state.  Finally the "run" script can exit with
-the status of the real test to let "git bisect run" command loop to
-know the outcome.
+* Automatically bisect a broken test suite:
++
+------------
+$ cat ~/test.sh
+#!/bin/sh
+make || exit 125                   # this skips broken builds
+make test                          # "make test" runs the test suite
+$ git bisect start v1.3 v1.1 --    # v1.3 is bad, v1.1 is good
+$ git bisect run ~/test.sh
+------------
++
+Here we use a "test.sh" custom script. In this script, if "make"
+fails, we skip the current commit.
++
+It is safer to use a custom script outside the repository to prevent
+interactions between the bisect, make and test processes and the
+script.
++
+"make test" should "exit 0", if the test suite passes, and
+"exit 1" otherwise.
+
+* Automatically bisect a broken test case:
++
+------------
+$ cat ~/test.sh
+#!/bin/sh
+make || exit 125                     # this skips broken builds
+~/check_test_case.sh                 # does the test case passes ?
+$ git bisect start HEAD HEAD~10 --   # culprit is among the last 10
+$ git bisect run ~/test.sh
+------------
++
+Here "check_test_case.sh" should "exit 0" if the test case passes,
+and "exit 1" otherwise.
++
+It is safer if both "test.sh" and "check_test_case.sh" scripts are
+outside the repository to prevent interactions between the bisect,
+make and test processes and the scripts.
+
+* Automatically bisect a broken test suite:
++
+------------
+$ git bisect start HEAD HEAD~10 --   # culprit is among the last 10
+$ git bisect run sh -c "make || exit 125; ~/check_test_case.sh"
+------------
++
+Does the same as the previous example, but on a single line.
 
 Author
 ------
@@ -199,5 +321,4 @@ Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
 
 GIT
 ---
-Part of the gitlink:git[7] suite
-
+Part of the linkgit:git[1] suite