Bug #106330 for Git-Repository: I'd like to be able to run interactive commands via Git::Repository

Mon Aug 10 10:54:20 2015 TIMB [...] cpan.org - Ticket created

Subject:

I'd like to be able to run interactive commands via Git::Repository

I'd like to be able to run interactive commands via Git::Repository to make use of the many features like setting cwd, git command, environment, fatal etc. I understand it wouldn't be able to control input or output, but that's ok. For example: $status = $repo->run("merge", ..., { interactive => 1 }) or $status = $repo->run_interactive("merge", ...) I presume this would require extending System::Command, e.g. to not alter stdin/stdout/stderr.

Mon Aug 10 11:03:27 2015 TIMB [...] cpan.org - Correspondence added

A rather hackish quick-fix that could still be useful would be to add a system() method that simply calls the built-in system() after the appropriate chdir and localized %ENV alterations. Something like: $gitrepo->system($gitrepo->git_cmd, @args); (and chdir back afterwards, naturally). Just a thought.

Mon Aug 10 12:56:10 2015 book [...] cpan.org - Correspondence added

On Mon Aug 10 10:54:20 2015, TIMB wrote: Show quoted text

> I'd like to be able to run interactive commands via Git::Repository to > make use of the many features like setting cwd, git command, > environment, fatal etc. I understand it wouldn't be able to control > input or output, but that's ok.

I'm not sure I understand the use case. What do you mean by "interactive"? Things like the interactive version of some commands (rebase, add)? Or something else? -- BooK

Mon Aug 10 12:56:10 2015 The RT System itself - Status changed from 'new' to 'open'

Mon Aug 10 17:22:18 2015 TIMB [...] cpan.org - Correspondence added

Show quoted text

> What do you mean by "interactive"? > Things like the interactive version of some commands (rebase, add)? > Or something else?

Yes. Anything that would cause git to want to start an editor, for example.

Mon Aug 10 18:28:28 2015 book [...] cpan.org - Correspondence added

On Mon Aug 10 17:22:18 2015, TIMB wrote: Show quoted text

>

> > What do you mean by "interactive"? > > Things like the interactive version of some commands (rebase, add)? > > Or something else?

> > Yes. Anything that would cause git to want to start an editor, for example.

OK, but then I don't see what's missing from Git::Repository to do that. You can invoke git rebase, for example, and define your own EDITOR environment variable like this: $r->run( rebase => '-i', 'master', 'topic', { env => { EDITOR => ... } } ); I see git rebase also has a --exec option, so you can even have more control on what's going to be run. Maybe some of the other commands also have such an option. Git::Repository should be able to run any git command. run() will collect stdout and stderr for you, while command() will hand you the filehandles. What you do with them is up to you. Also, sometimes Git itself figures out it's not attached to a terminal, and behaves differently. See https://metacpan.org/pod/distribution/Git-Repository/lib/Git/Repository/Tutorial.pod#Process-the-output-of-git-shortlog for an example. Do you have a more specific example of the git commands you're trying to run, and how it does not behavas as you expect? Thanks, -- BooK

Thu Aug 13 06:04:18 2015 TIMB [...] cpan.org - Correspondence added

For example, in a repo where "git rebase -i"would open an editor, try this: perl -MGit::Repository -we 'Git::Repository->new->run("rebase","-i")' It hangs. Running pstree I see: perl,13354 -MGit::Repository -we Git::Repository->new->run("rebase","-i") └─git,13366 rebase -i └─git-rebase,13367 /usr/libexec/git-core/git-rebase -i └─vim,13440 /home/tim/trunk/comp/support_stripes/.git/rebase-merge/git-rebase-todo

Thu Aug 13 08:12:54 2015 book [...] cpan.org - Correspondence added

On Thu Aug 13 06:04:18 2015, TIMB wrote: Show quoted text

> For example, in a repo where "git rebase -i"would open an editor, try > this: > > perl -MGit::Repository -we 'Git::Repository->new->run("rebase","-i")' > > It hangs. Running pstree I see: > > perl,13354 -MGit::Repository -we Git::Repository->new->run("rebase","- > i") > └─git,13366 rebase -i > └─git-rebase,13367 /usr/libexec/git-core/git-rebase -i > └─vim,13440 > /home/tim/trunk/comp/support_stripes/.git/rebase-merge/git-rebase-todo

And what would be the expected behaviour? If the perl program is attached to a terminal (-t STDIN is true), then effectively run the EDITOR and wait until it's done? And if not attached to a terminal, just fail? Would that work for you? The fail case is easy: delete EDITOR from %ENV if -t STDIN is false. $ perl -Ilib -MGit::Repository -e '$r=Git::Repository->new; delete $ENV{EDITOR}; $r->run( qw( rebase -i master ) )' fatal: Terminal is dumb, but EDITOR unset Could not execute editor at -e line 1. If running in a terminal, then running system() would work. (And be portable, I think. At least more than trying to reattach the filehandles in the right place.) If you want to run the "interactive" command in a non-interactive way, i.e. have a program process the content of the file generated by git before handing control back to git, one way would be to put the whole command line in $ENV{EDITOR}. Sounds fragile and ugly, but I wonder if there are other ways to keep git waiting for the EDITOR to finish, while replacing the file by your own version (and avoiding race conditions). * * * I wonder if adding an 'interactive' option to System::Command is not the simplest and most generic way to handle this situation (at least when trying to handle the first two cases): when interactive is true, then die (in System::Command) if -t is false, and otherwise call system() instead of the internal spawn command. What do you think?

Thu Sep 17 19:40:18 2015 book [...] cpan.org - Correspondence added

On Thu Aug 13 08:12:54 2015, BOOK wrote: Show quoted text

> > I wonder if adding an 'interactive' option to System::Command is not > the simplest and most generic way to handle this situation (at least > when trying to handle the first two cases): when interactive is true, > then die (in System::Command) if -t is false, and otherwise call > system() > instead of the internal spawn command. >

System::Command version 1.114 now has an 'interactive' option.

Thu Sep 17 19:40:36 2015 book [...] cpan.org - Status changed from 'open' to 'resolved'