# [PATCH] Documentation: "bisect run" can be given bangs before the run script. 4 messages from 2007-05-03 to 2007-05-05. Participants: Christian Couder, Junio C Hamano, Uwe Kleine-König. Thread: https://gitlist.dev/t/7951 ## Christian Couder, 2007-05-03 05:06 Subject: [PATCH] Documentation: "bisect run" can be given bangs before the run script. Message-ID: <20070503070607.fa2ffe92.chriscool@tuxfamily.org> URL: https://gitlist.dev/e/20070503070607.fa2ffe92.chriscool%40tuxfamily.org ``` Signed-off-by: Christian Couder --- Hi Uwe and Junio, This is the documentation related to my latest patch: [RFC/PATCH] Bisect: add special treatment for bangs passed to "bisect run". (http://article.gmane.org/gmane.comp.version-control.git/45943) Thanks in advance, Christian. Documentation/git-bisect.txt | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/Documentation/git-bisect.txt b/Documentation/git-bisect.txt index 5f68ee1..a1cceb5 100644 --- a/Documentation/git-bisect.txt +++ b/Documentation/git-bisect.txt @@ -175,6 +175,12 @@ 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".) +You can use one or more "!" argument immediately after "git bisect +run" if you want to revert once or more times the "run" script exit +code, even if your current shell does not support the "!" +keyword. Reverting the exit code means 0 gives 1 and anything other +than 0 gives 0. + 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 -- 1.5.2.rc0.71.g4342-dirty ``` ## Junio C Hamano, 2007-05-03 05:29 Subject: Re: [PATCH] Documentation: "bisect run" can be given bangs before the run script. Message-ID: <7vmz0m3261.fsf@assigned-by-dhcp.cox.net> URL: https://gitlist.dev/e/7vmz0m3261.fsf%40assigned-by-dhcp.cox.net In-Reply-To: <20070503070607.fa2ffe92.chriscool@tuxfamily.org> ``` I am not convinced that '!' is a good extension for two and half reasons. * The expected use is not quite clear. If it is not used to run a custom test script but something stock as "make", by the nature of UNIX exit status convention, you are looking for the commit that _fixed_ some breakage (i.e. "which commit fixed the compilation error?"). While sometimes that is a useful thing to do, it feels somewhat of limited value. On the other hand, if you are running a custom test script, I do not think it is unreasonable to always require that a test script to signal "bad" with small non-zero, "good" with zero, and error with high non-zero status, as we already do. * How should this interact with the "high non-zero status means an error and we cannot bisect" return convention? * I was hoping that we can officially support "don't know, cannot test this one, please give me another" for interactive use, and at the same time allow the run-script used by "git bisect run" to signal such with a special exit value (perhaps "exit 42"). Taken together with the previous point, it is not clear how '!' should interact with such an enhancement. ``` ## Uwe Kleine-König, 2007-05-03 07:03 Subject: Re: [PATCH] Documentation: "bisect run" can be given bangs before the run script. Message-ID: <20070503070302.GA4491@informatik.uni-freiburg.de> URL: https://gitlist.dev/e/20070503070302.GA4491%40informatik.uni-freiburg.de In-Reply-To: <7vmz0m3261.fsf@assigned-by-dhcp.cox.net> ``` Hello, Junio C Hamano wrote: > I am not convinced that '!' is a good extension for two and half > reasons. > > * The expected use is not quite clear. If it is not used to > run a custom test script but something stock as "make", by > the nature of UNIX exit status convention, you are looking > for the commit that _fixed_ some breakage (i.e. "which commit > fixed the compilation error?"). While sometimes that is a > useful thing to do, it feels somewhat of limited value. > > On the other hand, if you are running a custom test script, I > do not think it is unreasonable to always require that a test > script to signal "bad" with small non-zero, "good" with zero, > and error with high non-zero status, as we already do. > > * How should this interact with the "high non-zero status means > an error and we cannot bisect" return convention? > > * I was hoping that we can officially support "don't know, > cannot test this one, please give me another" for interactive > use, and at the same time allow the run-script used by > "git bisect run" to signal such with a special exit value > (perhaps "exit 42"). Taken together with the previous point, > it is not clear how '!' should interact with such an > enhancement. Ack for all 2½ reasons. Uwe -- Uwe Kleine-König http://www.google.com/search?q=1+newton+in+kg*m+%2F+s%5E2 ``` ## Christian Couder, 2007-05-05 12:57 Subject: Re: [PATCH] Documentation: "bisect run" can be given bangs before the run script. Message-ID: <200705051457.03277.chriscool@tuxfamily.org> URL: https://gitlist.dev/e/200705051457.03277.chriscool%40tuxfamily.org In-Reply-To: <7vmz0m3261.fsf@assigned-by-dhcp.cox.net> ``` Hi Junio and Uwe, Le jeudi 3 mai 2007 07:29, Junio C Hamano a écrit : > I am not convinced that '!' is a good extension for two and half > reasons. > > * The expected use is not quite clear. If it is not used to > run a custom test script but something stock as "make", by > the nature of UNIX exit status convention, you are looking > for the commit that _fixed_ some breakage (i.e. "which commit > fixed the compilation error?"). While sometimes that is a > useful thing to do, it feels somewhat of limited value. Well, of course the main expected use is for something like "make" or "grep" or "./test_something.sh" where "test_something.sh" is an already existing script. Especially because "git bisect run ! grep foo bar.txt" seems to me like a nice way to find the commit that introduced "foo" in "bar.txt" and I have been frustrated that it does not work. (Perhaps "git blame" can do it too, but I think "git bisect run" should be faster and more specific.) > On the other hand, if you are running a custom test script, I > do not think it is unreasonable to always require that a test > script to signal "bad" with small non-zero, "good" with zero, > and error with high non-zero status, as we already do. I agree this is probably the most usefull use of "git bisect run". But sometimes, perhaps for a one shot use, you already have something that could work if only you could revert the exist status. I think it is a good idea to give user some rope for this case. > * How should this interact with the "high non-zero status means > an error and we cannot bisect" return convention? If you use a bare "! grep foobar /*/*" on the command line for example and you kill it before it's finished, you will still get a 0 exit code. This means that, with the bash "!" keyword, any error gives a "good" result. I think it's better to keep this behavior. If we still wants something that keeps the "high non-zero status means an error and we cannot bisect" return convention, then let's call it a "--not" option or something like that. I will implement that if you prefer. I can even implement both "!" and "--not" if you want. By the way I think that sometimes it could happens that any exit code other than 0 means a "bad" revision and not "we cannot bisect". In this case using "git bisect run ! ! my_script" can be usefull. > * I was hoping that we can officially support "don't know, > cannot test this one, please give me another" for interactive > use, and at the same time allow the run-script used by > "git bisect run" to signal such with a special exit value > (perhaps "exit 42"). Taken together with the previous point, > it is not clear how '!' should interact with such an > enhancement. My bang patch does not in any way prevents from adding such a "don't know, cannot test this one, please give me another" improvement. It's just another option to make "git bisect run" more convenient in some cases. Christian (a give them rope proponent). ```