# [BUG] Documentation: git log: --exit-code undocumented? 10 messages from 2014-12-01 to 2014-12-02. Participants: Sergey Organov, Junio C Hamano, David Kastrup, John Keeping. Thread: https://gitlist.dev/t/38085 ## Sergey Organov, 2014-12-01 11:50 Subject: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: <87zjb78u7g.fsf@osv.gnss.ru> URL: https://gitlist.dev/e/87zjb78u7g.fsf%40osv.gnss.ru ``` Hello, $ git help log | grep exit-code problems are found. Not compatible with --exit-code. $ What --exit-code does in "git log"? -- Sergey. ``` ## Junio C Hamano, 2014-12-01 16:29 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: URL: https://gitlist.dev/e/xmqqegsjqqox.fsf%40gitster.dls.corp.google.com In-Reply-To: <87zjb78u7g.fsf@osv.gnss.ru> ``` Sergey Organov writes: > Hello, > > $ git help log | grep exit-code > problems are found. Not compatible with --exit-code. > $ > > What --exit-code does in "git log"? It doesn't. That is why it is not listed. ``` ## Sergey Organov, 2014-12-01 16:32 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: <87wq6bgwl6.fsf@osv.gnss.ru> URL: https://gitlist.dev/e/87wq6bgwl6.fsf%40osv.gnss.ru In-Reply-To: ``` Junio C Hamano writes: > Sergey Organov writes: > >> Hello, >> >> $ git help log | grep exit-code >> problems are found. Not compatible with --exit-code. >> $ >> >> What --exit-code does in "git log"? > > It doesn't. That is why it is not listed. Then, how can --check possibly interfer with it? -- Sergey. ``` ## Junio C Hamano, 2014-12-01 16:37 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: URL: https://gitlist.dev/e/xmqqa937qqb7.fsf%40gitster.dls.corp.google.com In-Reply-To: <87wq6bgwl6.fsf@osv.gnss.ru> ``` Sergey Organov writes: > Junio C Hamano writes: > >> Sergey Organov writes: >> >>> Hello, >>> >>> $ git help log | grep exit-code >>> problems are found. Not compatible with --exit-code. >>> $ >>> >>> What --exit-code does in "git log"? >> >> It doesn't. That is why it is not listed. > > Then, how can --check possibly interfer with it? The description is shared with "git diff" and friends, which is invoked via "git log -p". As "log" does not give the exit code of individual "diff-tree" invocation for each commit, --exit-code option is irrelevant. ``` ## Sergey Organov, 2014-12-01 16:43 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: <87oarngw2b.fsf@osv.gnss.ru> URL: https://gitlist.dev/e/87oarngw2b.fsf%40osv.gnss.ru In-Reply-To: ``` Junio C Hamano writes: > Sergey Organov writes: > >> Junio C Hamano writes: >> >>> Sergey Organov writes: >>> >>>> Hello, >>>> >>>> $ git help log | grep exit-code >>>> problems are found. Not compatible with --exit-code. >>>> $ >>>> >>>> What --exit-code does in "git log"? >>> >>> It doesn't. That is why it is not listed. >> >> Then, how can --check possibly interfer with it? > > The description is shared with "git diff" and friends, which is > invoked via "git log -p". As "log" does not give the exit code > of individual "diff-tree" invocation for each commit, --exit-code > option is irrelevant. Do you agree there is some minor problem here? First, "git log" silently eats the --exit-code option that does nothing. Next, git-log manual page doesn't include --exit-log description while refers to it elsewhere. What's proposed resulution? -- Sergey. ``` ## David Kastrup, 2014-12-01 17:32 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: <874mtfl1hx.fsf@fencepost.gnu.org> URL: https://gitlist.dev/e/874mtfl1hx.fsf%40fencepost.gnu.org In-Reply-To: ``` Junio C Hamano writes: > Sergey Organov writes: > >> Hello, >> >> $ git help log | grep exit-code >> problems are found. Not compatible with --exit-code. >> $ >> >> What --exit-code does in "git log"? > > It doesn't. That is why it is not listed. I disagree that --exit-code does nothing: it indicates whether the listed log is empty. So for example git log -1 --exit-code a..b > /dev/null can be used to figure out whether "a" is a proper ancestor of "b" or not. -- David Kastrup ``` ## Junio C Hamano, 2014-12-01 17:49 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: URL: https://gitlist.dev/e/xmqqwq6bp8ey.fsf%40gitster.dls.corp.google.com In-Reply-To: <874mtfl1hx.fsf@fencepost.gnu.org> ``` David Kastrup writes: > I disagree that --exit-code does nothing: it indicates whether the > listed log is empty. So for example > > git log -1 --exit-code a..b > /dev/null > > can be used to figure out whether "a" is a proper ancestor of "b" or > not. Hmph. $ git log --exit-code master..maint >/dev/null; echo $? 0 $ git log --exit-code maint..master >/dev/null; echo $? 1 That is a strange way to use --exit-code. I suspect that if you did this, you will get 0 from the log between HEAD~..HEAD $ git checkout master^0 $ git commit --allow-empty -m empty $ git log --exit-code HEAD~..HEAD even though HEAD~ is a proper ancestor of HEAD, so it is not giving us anything useful. Isn't it a mere artifact that "log" happens to share the underlying machinery with "diff" that --exit-code shows a non-zero exit when there is any single commit in the range that has any change? ``` ## David Kastrup, 2014-12-01 18:30 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: <87zjb7jk8q.fsf@fencepost.gnu.org> URL: https://gitlist.dev/e/87zjb7jk8q.fsf%40fencepost.gnu.org In-Reply-To: ``` Junio C Hamano writes: > David Kastrup writes: > >> I disagree that --exit-code does nothing: it indicates whether the >> listed log is empty. So for example >> >> git log -1 --exit-code a..b > /dev/null >> >> can be used to figure out whether "a" is a proper ancestor of "b" or >> not. > > Hmph. > > $ git log --exit-code master..maint >/dev/null; echo $? > 0 > $ git log --exit-code maint..master >/dev/null; echo $? > 1 > > That is a strange way to use --exit-code. I suspect that if you did > this, you will get 0 from the log between HEAD~..HEAD > > $ git checkout master^0 > $ git commit --allow-empty -m empty > $ git log --exit-code HEAD~..HEAD > > even though HEAD~ is a proper ancestor of HEAD, so it is not giving > us anything useful. Isn't it a mere artifact that "log" happens to > share the underlying machinery with "diff" that --exit-code shows a > non-zero exit when there is any single commit in the range that has > any change? Possibly: I haven't checked the underlying code for the details. At any rate, it is an option git log accepts for whatever reason. -- David Kastrup ``` ## Sergey Organov, 2014-12-02 11:30 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: <87ppc2xp9k.fsf@osv.gnss.ru> URL: https://gitlist.dev/e/87ppc2xp9k.fsf%40osv.gnss.ru In-Reply-To: ``` Junio C Hamano writes: > David Kastrup writes: > >> I disagree that --exit-code does nothing: it indicates whether the >> listed log is empty. So for example >> >> git log -1 --exit-code a..b > /dev/null >> >> can be used to figure out whether "a" is a proper ancestor of "b" or >> not. > > Hmph. > > $ git log --exit-code master..maint >/dev/null; echo $? > 0 > $ git log --exit-code maint..master >/dev/null; echo $? > 1 > > That is a strange way to use --exit-code. What's the best way then to tell if "a" is an ancestor of "b"? -- Sergey. ``` ## John Keeping, 2014-12-02 12:27 Subject: Re: [BUG] Documentation: git log: --exit-code undocumented? Message-ID: <20141202122705.GA22967@serenity.lan> URL: https://gitlist.dev/e/20141202122705.GA22967%40serenity.lan In-Reply-To: <87ppc2xp9k.fsf@osv.gnss.ru> ``` On Tue, Dec 02, 2014 at 02:30:31PM +0300, Sergey Organov wrote: > Junio C Hamano writes: > > > David Kastrup writes: > > > >> I disagree that --exit-code does nothing: it indicates whether the > >> listed log is empty. So for example > >> > >> git log -1 --exit-code a..b > /dev/null > >> > >> can be used to figure out whether "a" is a proper ancestor of "b" or > >> not. > > > > Hmph. > > > > $ git log --exit-code master..maint >/dev/null; echo $? > > 0 > > $ git log --exit-code maint..master >/dev/null; echo $? > > 1 > > > > That is a strange way to use --exit-code. > > What's the best way then to tell if "a" is an ancestor of "b"? git merge-base --is-ancestor a b ```