Re: [PATCH] Bisect: add checks at the beginning of "git bisect run".

Christian Couder [off-list ref] writes:

git bisect run --not grep string my_file

instead of something like

git bisect run ! grep string my_file

How's the former more useful than the latter was what I was
wondering but I do not care too deeply.

For example one could write:

git bisect run --good rev1 --bad rev2 my_script

instead of

git bisect start
git bisect good rev1
git bisect bad rev2
git bisect run my_script

Likewise.

quoted

quoted

--check or --test
run the script once and then do nothing if the result is good

How would you use this? 

For example if you know that the last nightly build 
tagged "nightly_2007_03_27" was ok, you could use:

git bisect start
git bisect good nightly_2007_03_27
git bisect run --check make > /dev/null || {
	# extract commit and author email address from "$GIT_DIR/BISECT_RUN"
	# and send flame to author who broke the build with the commit
}

to automatically check that current source code builds ok.

As I said, bisect fundamentally needs one bad commit to start
bisecting, so after you give only one good commit, it would not
move to bisect branch nor suggest which commit to test.  I
assume you intend to run the test on the tip of the current
branch here, but then your "git bisect run --check ./run-script"
is equivalent to running ./run-script and checking the exit
value.

In other words, the above would be equilvalent to

  git bisect start
  git bisect good nightly_2007_03_27
  make >/dev/null || {
	  git bisect bad
          git bisect run make >/dev/null
          # extract commit and author email address from "$GIT_DIR/BISECT_RUN"
          # and send flame to author who broke the build with the commit
  }

I happen to find the latter easier to read as a shell script.