On 3/3/21 5:27 PM, Junio C Hamano wrote:
"Josh Hunt via GitGitGadget" <gitgitgadget@xxxxxxxxx> writes:
From: Josh Hunt <johunt@xxxxxxxxxx>
Currently git branch --list foo always returns an exit status of 0 even
when the branch being searched for does not exist. Now an error is printed
and returns a non-zero exit status.
Junio
Thanks so much for the review.
Explaining what happens in the current code upfront is a good thing
and is in line with the convention used in our project, which is
good. But drop "currently" from there.
Strictly speaking, it is not "always". In a corrupt repository, it
is likely to show a proper error message and die.
Also explaining what you want to happen before the end of the log
message is good.
Thank you. I will make the above changes to the commit message if this
moves forward.
But the proposed log message lacks why it is a good idea to make
such a change, which is the most important part.
OK sure. To provide better context I came across this when using 'git
branch --list foo' in a script and there was an expectation (possibly
incorrect) when the search was not successful it would return an
non-zero exit status.
I don't know if there's a convention that git follows, but I have the
following examples where a similar type of command does return a
non-zero exit status:
johunt@johunt-ThinkPad-T480s:~$ ls foo
ls: cannot access 'foo': No such file or directory
johunt@johunt-ThinkPad-T480s:~$ echo $?
2
johunt@johunt-ThinkPad-T480s:~$ touch foo
johunt@johunt-ThinkPad-T480s:~$ grep bar foo
johunt@johunt-ThinkPad-T480s:~$ echo $?
1
johunt@johunt-ThinkPad-T480s:~$ grep . foo
grep: foo: No such file or directory
johunt@johunt-ThinkPad-T480s:~$ echo $?
2
Not just these tools, but even in git itself:
johunt@johunt-ThinkPad-T480s:~$ git init foo
Initialized empty Git repository in /home/johunt/foo/.git/
johunt@johunt-ThinkPad-T480s:~/foo$ touch bar
johunt@johunt-ThinkPad-T480s:~/foo$ git add bar
johunt@johunt-ThinkPad-T480s:~/foo$ git commit -am 'initial commit'
[master (root-commit) 771510f] initial commit
1 file changed, 0 insertions(+), 0 deletions(-)
create mode 100644 bar
johunt@johunt-ThinkPad-T480s:~/foo$ git log foo
fatal: ambiguous argument 'foo': unknown revision or path not in the
working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
johunt@johunt-ThinkPad-T480s:~/foo$ echo $?
128
johunt@johunt-ThinkPad-T480s:~/foo$ git grep foo .
johunt@johunt-ThinkPad-T480s:~/foo$ echo $?
1
However it does seem like 'tag --list' follows the branch behavior:
johunt@johunt-ThinkPad-T480s:~/foo$ git tag --list foo
johunt@johunt-ThinkPad-T480s:~/foo$ echo $?
0
There are likely other examples of git commands showing both behaviors.
Is it that branch and tag are a certain type of command which allows
them to behave differently than say log or grep?
If you ask me, I would say that the command was asked to show any
branches, if exist, that match the given pattern, and did what it
was asked to do without encountering any error---it just happened to
have seen 0 branch that matched. So I think returning non-zero
status would be a bug.
Interesting. Going back to the scripting context then your suggestion
would just be to check if output is NULL? This is what I've converted my
scripts to do for now, but still feel like if --list can't find the
branch I'm looking for then it should return non-zero as it matches
behavior of other tools :)
Josh
