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I would like to create a function that runs a command only after a previous command that takes some input from the user finishes running. In particular, I would like to write a function that runs a command after magit-pull:

(defun test ()
  (interactive)
  (call-interactively 'magit-pull)
  (read-key)
  (command)
)

The above function works only when magit-pull does not ask me for a password. However, when magit-pull asks me to enter my password in the minibufer, the above code won't work. I suppose I need to add some code that will only run "command" only after magit-pull is finished. Does anyone know of how I can implement this?

Drew
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falsum
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  • Add an advice to magic-pull. Check if there is a magit-pull-hook? – John Kitchin Feb 16 '17 at 22:48
  • @John Kitchin : I didn't find a magit-pull-hook but, as expected, magit has other hooks available that I might try using. How would you use a hook in this case? – falsum Feb 17 '17 at 00:54
  • http://emacs.stackexchange.com/a/16558/7045 – Emacs User Feb 17 '17 at 03:14
  • @EmacsUser : if I understood your suggestion correctly, adding something to a magit hook with 'add-hook' seems to have uninted consequences. For instance, with '(add-hook 'git-commit-mode-hook (lambda () (command)))' would run 'command' every time you enter or leave git-commit-mode. – falsum Feb 17 '17 at 03:47
  • Generally speaking, tools to accomplish this objective are in the nature of a process sentinel and/or recursive-edit. http://stackoverflow.com/questions/23237869/fine-tuning-set-process-sentinel-set-process-filter-start-process In terms of magit-pull, I'll leave that for Tarsius or another forum participant. – lawlist Feb 17 '17 at 05:21
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    If there is no magit-pull-hook then it is not likely another hook would work for you. See http://stackoverflow.com/questions/5623208/how-to-execute-a-command-right-after-a-fetch-or-pull-command-in-git for a way to setup a git hook function that will probably work for you. – John Kitchin Feb 17 '17 at 12:54
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    I suspect the real problem here is that magit-pull is calling some asynchronous code. I don't think it should matter whether or not the user is prompted for input. If the code is synchronous, the subsequent commands won't run until after the user makes their input. – Tyler Feb 17 '17 at 22:20

1 Answers1

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A general solution to "do something after another command" is to use advice, as suggested in the comments above. 

(defun after-magit-pull ()
  "Some function to run after `magit-pull`.")
  (whatever))

(advice-add 'magit-pull :after 'after-magit-pull)

Whether this is the best way to accomplish your goal is a slightly different question. Using a git hook may be more appropriate, again as noted in the comments.

Update

Looking at magit-pull a bit more, using advice does not seem appropriate for this particular case. Magit starts git processes asynchronously and uses magit-process-sentinel to wait for the git process to complete so that it can do some additional work (like refreshing buffers). So :after advice on a command like magit-pull will probably run before the underlying git process actually completes.

To take some action after a git command finishes you might be able to use the magit-post-refresh-hook. I haven't tried this, but you could create your own command that adds an additional function to the post-refresh hook -- one that removes itself when it is done -- and then calling magit-pull.

glucas
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  • My understanding is that this will advise magit-pull every time I call it. I guess I could use advice-remove at the end of the function to change that. – falsum Feb 17 '17 at 21:36
  • Unless I'm doing something stupid, the code above works when instead of using magit-pull I use an non-interactive function (e.g., bury-buffer). Do I need to change anything when using advice-add to apply to interactive functions? – falsum Feb 17 '17 at 21:42
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    The command bury-buffer is also interactive -- in elisp any command you can invoke via M-x is interactive, and advice works in either case. However, magit-pull is a bit more complicated: magit is starting git processes, sometimes asynchronously. In that case advice is not appropriate because the advised function will finish before the external git process returns. – glucas Feb 18 '17 at 16:00