[PATCH 1/2] bash: Enable completion for external subcommands

[Teemu Matilainen <teemu.matilainen@iki.fi>]

Now the parameter completion is only available for subcommands
delivered with git.  Providers of external subcommands do not have
a way to supply bash completion for their commands (other than
instructing users to hack their git-completion.bash file).

This makes it possible to have completion also for external git
subcommands.  It can be provided by specifying a function (or a
command in PATH) '_git_<subcommand>' that sets the environment
variable COMPREPLY.

All dashes (-) in the subcommand name are replaced with underscores
(_).  E.g. completion for command 'git foo-bar' can be provided by
'_git_foo_bar'.

Signed-off-by: Teemu Matilainen <teemu.matilainen@iki.fi>
---
 contrib/completion/git-completion.bash |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index fe93747..c7ac727 100755
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -14,6 +14,9 @@
 #    *) git 'subcommands'
 #    *) tree paths within 'ref:path/to/file' expressions
 #    *) common --long-options
+#    *) completion for external 'git <sub-command>' can be provided by
+#       specifying function (or command in PATH) '_git_<sub_command>'
+#       that sets COMPREPLY
 #
 # To use these routines:
 #
@@ -2257,7 +2260,10 @@ _git ()
 	svn)         _git_svn ;;
 	tag)         _git_tag ;;
 	whatchanged) _git_log ;;
-	*)           COMPREPLY=() ;;
+	*)
+		local f="_git_${command//-/_}"
+		type -t "$f" >/dev/null && "$f" || COMPREPLY=()
+		;;
 	esac
 }
 
-- 
1.7.0.83.g241b9