Re: rev-list pretty format behavior
Heyup, Dr. Gruber. On 7 April 2015 at 15:53, Michael J Gruber g...@drmicha.warpmail.net wrote: I'm wondering what the difference is - or should be - between git log and git rev-list with (completely) user specified output. That question goes both ways: - Why do we need rev-list to have completely flexible output when we have log with such flexibility? - Why do we even have pretty formats for rev-list? I'm thinking of rev-list as a raw (plumbing) revision lister much like cat-file is the inspection tool for the objects, and log as the human facing output with appropriate defaults (resp. show). Note that rev-list -v isn't even documented afaics. I can't answer your questions, because I don't have a very deep understanding of either command, but according to the log docu, formating really belongs to rev-list and log only adds the diff-* features: -- The command takes options applicable to the git rev-list command to control what is shown and how, and options applicable to the git diff-* commands to control how the changes each commit introduces are shown. -- I also feel that perhaps pretty is a bit of a misnomer and naturally is associated with human readable, but the formating is vital for any raw output that scripts can process. Oliver -- To unsubscribe from this list: send the line unsubscribe git in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: rev-list pretty format behavior
Oliver Runge venit, vidit, dixit 06.04.2015 13:05:
Hallo, Mr. Hamano.
Thank you for your quick and detailed response.
On 5 April 2015 at 23:12, Junio C Hamano gits...@pobox.com wrote:
This is very much the designed behaviour, I would think. IIRC, the
user-format support of rev-list was designed so that the scripts
can customize the output from rev-list -v, which was how scripts
were expected to read various pieces of information for each commit
originally. And the 40-hex commit object name and/or a line that
begins with commit ... when a user format is used are meant to
serve as stable record separator (in that sense, having %H or %h in
the userformat given to rev-list is redundant) when these scripts
are reading output from rev-list.
I see, but then I find it even stranger, because rev-list -v without
pretty parameter will only output the hash as separator and commit
sha1 is only introduced if a pretty parameter other than
oneline is specified. The docu states the formating is intended to
make git rev-list behave more like git log, and apart from the
pretty settings email and format/tformat (which don't have
commit sha1 in git log) the formating works exactly like it does
in git log.
docu:
--
Commit Formatting
Using these options, git-rev-list(1) will act similar to the more
specialized family of commit log tools: git-log(1), git-show(1),
and git-whatchanged(1)
--
and
--
- format:string
The format:string format allows you to specify which information you
want to show. It works a little bit like printf format, with the
notable exception that you get a newline with %n instead of \n.
E.g, format:The author of %h was %an, %ar%nThe title was %s%n
would show something like this:
The author of fe6e0ee was Junio C Hamano, 23 hours ago
The title was t4119: test autocomputing -pn for traditional
diff input.
--
A new option to tell rev-list that I am designing an output that
is a-line-per-commit with the userformat and do not need the default
record separator or I will arrange record separator myself would
be an acceptable thing to add, provided if many scripts yet to be
written would benefit from such a feature, though.
I searched github for usages of git rev-list --pretty=format to see
whether I'm alone. I realize this is merely anecdotal, but perhaps
still useful.
Scripts ignoring the separator:
--
# no idea why it always prints those commit lines
git rev-list --pretty=format: - %s $@ |grep -v ^commit
--
--
git rev-list --pretty=format:%H %h|%an:%s $@ | sed -n
s/^\([0-9a-f]\{40\}\) \(.*\)$/n\1 [$shape label=\{\2}\]/p
--
(shortened with ... by me)
--
git rev-list --pretty=format:%H %h %d $@ | awk '
...
!/^commit/ {
...
}'
--
Most of the scripts I found hack around the commit sha1 lines,
mostly in a way that would still work if the lines suddenly weren't
there anymore. But unfortunately there are also some examples that
would break:
--
git rev-list --oneline --pretty=format:%C(yellow)%h
%C(red)%ad%C(green)%d %C(reset)%s%C(cyan) [%cn] --date=short
HEAD~2..HEAD | awk 'NR % 2 == 0'
--
And finally there are a few that really use the current behavior:
--
# tcl
set revisions [$::versioned_interpreter git rev-list
--pretty=format:%at%n%an %ae%n%s -n 10 $revision]
set result {}
foreach {commit date author summary} [split $revisions \n] {
lappend result [list [lindex $commit 1] $date $author $summary]
}
--
(shortened with ... by me)
--
save()
{
awk '{print $2 '$1' }' | sort $R/sha/$1
}
...
make_sha()
{
git rev-list --pretty=format: ^Research-V6 BSD-1 | save BSD-1
git rev-list --pretty=format: ^BSD-1 BSD-2 | save BSD-2
...
}
--
I really feel that it should be the default behavior for format,
since the separator intention isn't described in the docu and isn't
really needed for scripts that want to provide their own formating.
That being said, I understand that that's likely not going to happen,
especially since it would break quite a few legacy scripts.
But it would be prudent to update the docu to highlight the different
behavior for the pretty settings email and format/tformat, and
even though I think another feature to turn off the separator lines
makes the command more complex, the fact that so many scripts
Re: rev-list pretty format behavior
Hallo, Mr. Hamano.
Thank you for your quick and detailed response.
On 5 April 2015 at 23:12, Junio C Hamano gits...@pobox.com wrote:
This is very much the designed behaviour, I would think. IIRC, the
user-format support of rev-list was designed so that the scripts
can customize the output from rev-list -v, which was how scripts
were expected to read various pieces of information for each commit
originally. And the 40-hex commit object name and/or a line that
begins with commit ... when a user format is used are meant to
serve as stable record separator (in that sense, having %H or %h in
the userformat given to rev-list is redundant) when these scripts
are reading output from rev-list.
I see, but then I find it even stranger, because rev-list -v without
pretty parameter will only output the hash as separator and commit
sha1 is only introduced if a pretty parameter other than
oneline is specified. The docu states the formating is intended to
make git rev-list behave more like git log, and apart from the
pretty settings email and format/tformat (which don't have
commit sha1 in git log) the formating works exactly like it does
in git log.
docu:
--
Commit Formatting
Using these options, git-rev-list(1) will act similar to the more
specialized family of commit log tools: git-log(1), git-show(1),
and git-whatchanged(1)
--
and
--
- format:string
The format:string format allows you to specify which information you
want to show. It works a little bit like printf format, with the
notable exception that you get a newline with %n instead of \n.
E.g, format:The author of %h was %an, %ar%nThe title was %s%n
would show something like this:
The author of fe6e0ee was Junio C Hamano, 23 hours ago
The title was t4119: test autocomputing -pn for traditional
diff input.
--
A new option to tell rev-list that I am designing an output that
is a-line-per-commit with the userformat and do not need the default
record separator or I will arrange record separator myself would
be an acceptable thing to add, provided if many scripts yet to be
written would benefit from such a feature, though.
I searched github for usages of git rev-list --pretty=format to see
whether I'm alone. I realize this is merely anecdotal, but perhaps
still useful.
Scripts ignoring the separator:
--
# no idea why it always prints those commit lines
git rev-list --pretty=format: - %s $@ |grep -v ^commit
--
--
git rev-list --pretty=format:%H %h|%an:%s $@ | sed -n
s/^\([0-9a-f]\{40\}\) \(.*\)$/n\1 [$shape label=\{\2}\]/p
--
(shortened with ... by me)
--
git rev-list --pretty=format:%H %h %d $@ | awk '
...
!/^commit/ {
...
}'
--
Most of the scripts I found hack around the commit sha1 lines,
mostly in a way that would still work if the lines suddenly weren't
there anymore. But unfortunately there are also some examples that
would break:
--
git rev-list --oneline --pretty=format:%C(yellow)%h
%C(red)%ad%C(green)%d %C(reset)%s%C(cyan) [%cn] --date=short
HEAD~2..HEAD | awk 'NR % 2 == 0'
--
And finally there are a few that really use the current behavior:
--
# tcl
set revisions [$::versioned_interpreter git rev-list
--pretty=format:%at%n%an %ae%n%s -n 10 $revision]
set result {}
foreach {commit date author summary} [split $revisions \n] {
lappend result [list [lindex $commit 1] $date $author $summary]
}
--
(shortened with ... by me)
--
save()
{
awk '{print $2 '$1' }' | sort $R/sha/$1
}
...
make_sha()
{
git rev-list --pretty=format: ^Research-V6 BSD-1 | save BSD-1
git rev-list --pretty=format: ^BSD-1 BSD-2 | save BSD-2
...
}
--
I really feel that it should be the default behavior for format,
since the separator intention isn't described in the docu and isn't
really needed for scripts that want to provide their own formating.
That being said, I understand that that's likely not going to happen,
especially since it would break quite a few legacy scripts.
But it would be prudent to update the docu to highlight the different
behavior for the pretty settings email and format/tformat, and
even though I think another feature to turn off the separator lines
makes the command more complex, the fact that so many scripts seem to
write around the behavior might justify it.
I'd like to help with both tasks, if you think they are reasonable.
Oliver
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Re: rev-list pretty format behavior
Oliver Runge oliver.ru...@gmail.com writes: I'm using git version 2.4.0-rc1. The same behavior exists in 2.1.0. Trying the same with rev-list results in: git rev-list --pretty=format:%h ... HEAD~3...HEAD commit 826aed50cbb072d8f159e4c8ba0f9bd3df21a234 826aed5 ... commit 915e44c6357f3bd9d5fa498a201872c4367302d3 915e44c ... commit 067178ed8a7822e6bc88ad606b707fc33658e6fc 067178e ... This is very much the designed behaviour, I would think. IIRC, the user-format support of rev-list was designed so that the scripts can customize the output from rev-list -v, which was how scripts were expected to read various pieces of information for each commit originally. And the 40-hex commit object name and/or a line that begins with commit ... when a user format is used are meant to serve as stable record separator (in that sense, having %H or %h in the userformat given to rev-list is redundant) when these scripts are reading output from rev-list. A new option to tell rev-list that I am designing an output that is a-line-per-commit with the userformat and do not need the default record separator or I will arrange record separator myself would be an acceptable thing to add, provided if many scripts yet to be written would benefit from such a feature, though. -- To unsubscribe from this list: send the line unsubscribe git in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
