# "git describe" documentation and behavior mismatch 6 messages from 2017-11-30 to 2017-12-15. Participants: Daniel Knittl-Frank, Junio C Hamano. Thread: https://gitlist.dev/t/47357 ## Daniel Knittl-Frank, 2017-11-30 18:47 Subject: "git describe" documentation and behavior mismatch Message-ID: URL: https://gitlist.dev/e/CACx-yZ10GiDT%3DdDeF1EUtM_K4nGd414SDfxLRqGWyXt0ub02Gg%40mail.gmail.com ``` Hi Git list, the help page/manpage of the git describe command has an example with the --all flag which should prepend the ref namespace (tags/ or heads/): > With --all, the command can use branch heads as references, so the output shows the reference path as well: > > [torvalds@g5 git]$ git describe --all --abbrev=4 v1.0.5^2 > tags/v1.0.0-21-g975b > > [torvalds@g5 git]$ git describe --all --abbrev=4 HEAD^ > heads/lt/describe-7-g975b Running the above commands in the git.git repository yields a different result: > $ git describe --all --abbrev=4 v1.0.5^2 > v1.0.0-21-g975b3 No "reference path" to see. It is however shown, when the output is a branch name: > $ git describe --all --abbrev=4 origin/next > heads/next Is this expected behavior? IOW is the documentation outdated or is the git describe command misbehaving? Thanks, Daniel -- typed with http://neo-layout.org ``` ## Daniel Knittl-Frank, 2017-11-30 19:26 Subject: Re: "git describe" documentation and behavior mismatch Message-ID: URL: https://gitlist.dev/e/CACx-yZ1dJuUj5mD6WE8yqZCPMK8q-yaJ0GKUSppZ7uDkqvJ5UA%40mail.gmail.com In-Reply-To: ``` On Thu, Nov 30, 2017 at 7:47 PM, Daniel Knittl-Frank wrote: > […] > > Running the above commands in the git.git repository yields a different result: > >> $ git describe --all --abbrev=4 v1.0.5^2 >> v1.0.0-21-g975b3 > > No "reference path" to see. It is however shown, when the output is a > branch name: > >> $ git describe --all --abbrev=4 origin/next >> heads/next > > Is this expected behavior? IOW is the documentation outdated or is the > git describe command misbehaving? Bisecting history goes as far back as Feb 2008: commit 212945d4a85dfa172ea55ec73b1d830ef2d8582f > Teach git-describe to verify annotated tag names before output The warning mentioned in the commit message has since been gone. So I guess the documentation is outdated? Nobody has complained for the past 9 years, so we could call this a "feature" :) An interesting fact (and intentional behavior?) is that describing a commit with only a lightweight tag will properly display the tags/ prefix. I assume this is because the annotated tags only store the tagname without any ref namespace, which is then picked up by git describe and displayed. I will try to come up with a patch for the man page. Daniel -- typed with http://neo-layout.org ``` ## Junio C Hamano, 2017-12-03 05:39 Subject: Re: "git describe" documentation and behavior mismatch Message-ID: URL: https://gitlist.dev/e/xmqqefocjrp2.fsf%40gitster.mtv.corp.google.com In-Reply-To: ``` Daniel Knittl-Frank writes: > An interesting fact (and intentional behavior?) is that describing a > commit with only a lightweight tag will properly display the tags/ > prefix. I assume this is because the annotated tags only store the > tagname without any ref namespace, which is then picked up by git > describe and displayed. I suspect that "see if the name recorded in the tag object matches the name of the ref that stores the tag after refs/tags/" code *is* not just verifying what it claims to (which may be good) but also unintentionally affecting the output (i.e. "--all" promises that the prefix tags/ should be shown). Perhaps the code needs to be fixed if that is the case. ``` ## Daniel Knittl-Frank, 2017-12-11 18:34 Subject: Re: "git describe" documentation and behavior mismatch Message-ID: URL: https://gitlist.dev/e/CACx-yZ1DGz2z6qqAX%3DpzeExT689y0sON%2BwVDaocdWk75a5SOxA%40mail.gmail.com In-Reply-To: ``` On Sun, Dec 3, 2017 at 6:39 AM, Junio C Hamano wrote: > I suspect that "see if the name recorded in the tag object matches > the name of the ref that stores the tag after refs/tags/" code *is* > not just verifying what it claims to (which may be good) but also > unintentionally affecting the output (i.e. "--all" promises that the > prefix tags/ should be shown). Perhaps the code needs to be fixed > if that is the case. What is the course of action then? I wrote up a really dumb 2-line patch which simply checks if --all was specified and prepends the output with "tags/". Good enough? Should we instead update the documentation? Still not sure, what the behavior _should_ be in the case of annotated tags with embedded names. -- >8 -- From 7243d700aad280b11e647e04ade027c412dde54c Mon Sep 17 00:00:00 2001 From: Daniel Knittl-Frank Date: Mon, 11 Dec 2017 19:24:54 +0100 Subject: [PATCH] Prepend "tags/" when describing tags with embedded name Signed-off-by: Daniel Knittl-Frank --- builtin/describe.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/builtin/describe.c b/builtin/describe.c index e14e162ef6..54aaf30562 100644 --- a/builtin/describe.c +++ b/builtin/describe.c @@ -272,6 +272,8 @@ static void display_name(struct commit_name *n) } if (n->tag) + if (all) + printf("tags/"); printf("%s", n->tag->tag); else printf("%s", n->path); -- 2.15.GIT -- typed with http://neo-layout.org ``` ## Daniel Knittl-Frank, 2017-12-11 18:37 Subject: Re: "git describe" documentation and behavior mismatch Message-ID: URL: https://gitlist.dev/e/CACx-yZ3FxqFvXgM-V0stODcyAdCoO83s%3DWwyZ2OLiJON6qqvkA%40mail.gmail.com In-Reply-To: ``` Forget the above patch. I should compile my code after refactoring ... Here is the fixed version. -- >8 -- From 8203bd0ad5baab7024ebff597c9f35a0250d09ff Mon Sep 17 00:00:00 2001 From: Daniel Knittl-Frank Date: Mon, 11 Dec 2017 19:24:54 +0100 Subject: [PATCH] Prepend "tags/" when describing tags with embedded name Signed-off-by: Daniel Knittl-Frank --- builtin/describe.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/builtin/describe.c b/builtin/describe.c index e14e162ef6..9da6d85ea3 100644 --- a/builtin/describe.c +++ b/builtin/describe.c @@ -271,10 +271,13 @@ static void display_name(struct commit_name *n) n->name_checked = 1; } - if (n->tag) + if (n->tag) { + if (all) + printf("tags/"); printf("%s", n->tag->tag); - else + } else { printf("%s", n->path); + } } static void show_suffix(int depth, const struct object_id *oid) -- 2.15.GIT -- typed with http://neo-layout.org ``` ## Junio C Hamano, 2017-12-15 19:25 Subject: Re: "git describe" documentation and behavior mismatch Message-ID: URL: https://gitlist.dev/e/xmqqwp1npzd8.fsf%40gitster.mtv.corp.google.com In-Reply-To: ``` Daniel Knittl-Frank writes: > Forget the above patch. I should compile my code after refactoring ... > > Here is the fixed version. > > -- >8 -- > > From 8203bd0ad5baab7024ebff597c9f35a0250d09ff Mon Sep 17 00:00:00 2001 > From: Daniel Knittl-Frank > Date: Mon, 11 Dec 2017 19:24:54 +0100 > Subject: [PATCH] Prepend "tags/" when describing tags with embedded name > > Signed-off-by: Daniel Knittl-Frank > --- > builtin/describe.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) I think the code makes sense, but it won't be understandable by those who do not know what you discussed in the original thread. A proper commit log message, with a new test or two in t6120, would be an appropriate way to fix that. Care to follow through, along the lines in Documentation/SubmittingPatches? Thanks. > diff --git a/builtin/describe.c b/builtin/describe.c > index e14e162ef6..9da6d85ea3 100644 > --- a/builtin/describe.c > +++ b/builtin/describe.c > @@ -271,10 +271,13 @@ static void display_name(struct commit_name *n) > n->name_checked = 1; > } > > - if (n->tag) > + if (n->tag) { > + if (all) > + printf("tags/"); > printf("%s", n->tag->tag); > - else > + } else { > printf("%s", n->path); > + } > } > > static void show_suffix(int depth, const struct object_id *oid) > -- > 2.15.GIT ```