[TopGit PATCH] tg-undepend.sh: new command to remove a dependency.

[Jan Nieuwenhuizen <janneke-list@xs4all.nl>]

Here's a stab at removing a dependency from a topgit branch.

This is something we think we need for ooo-build to switch to git.

Signed-off-by: Jan Nieuwenhuizen <janneke@gnu.org>
---
 Makefile       |    2 +-
 README         |    5 ++++
 tg-undepend.sh |   57 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 1 deletions(-)
 create mode 100755 tg-undepend.sh

diff --git a/Makefile b/Makefile
index af46399..d40e509 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,7 @@ sharedir = $(prefix)/share/topgit
 hooksdir = $(cmddir)/hooks
 
 
-commands_in = tg-create.sh tg-delete.sh tg-export.sh tg-info.sh tg-patch.sh tg-summary.sh tg-update.sh
+commands_in = tg-create.sh tg-delete.sh tg-export.sh tg-info.sh tg-patch.sh tg-summary.sh tg-undepend.sh tg-update.sh
 hooks_in = hooks/pre-commit.sh
 
 commands_out = $(patsubst %.sh,%,$(commands_in))
diff --git a/README b/README
index b58a1b4..096b9ec 100644
--- a/README
+++ b/README
@@ -330,6 +330,11 @@ tg export
 	TODO: Make stripping of [PATCH] and other prefixes configurable
 	TODO: --mbox option for other mode of operation
 
+tg undepend
+~~~~~~~~~~~
+	Update the current topic branch by removing the given
+	branch (required argument) from the list of dependencies.
+
 tg update
 ~~~~~~~~~
 	Update the current topic branch wrt. changes in the branches
diff --git a/tg-undepend.sh b/tg-undepend.sh
new file mode 100755
index 0000000..d4c0143
--- /dev/null
+++ b/tg-undepend.sh
@@ -0,0 +1,57 @@
+#! /bin/sh
+# TopGit - A different patch queue manager
+# (c) Petr Baudis <pasky@suse.cz>  2008
+# (c) 2008  Jan Nieuwenhuizen <janneke@gnu.org>
+# GNU GPL version 2
+
+name=
+
+
+## Parse options
+
+while [ -n "$1" ]; do
+	arg="$1"; shift
+	case "$arg" in
+	-*)
+		echo "Usage: tg undepend [NAME]" >&2
+		exit 2;;
+	*)
+		[ -z "$name" ] || die "name already specified ($name)"
+		name="$arg";;
+	esac
+done
+
+[ -n "$name" ] || name="$(git symbolic-ref HEAD | sed 's#^refs/heads/##')"
+base_rev="$(git rev-parse --short --verify "refs/top-bases/$name" 2>/dev/null)" \
+	|| die "not a TopGit-controlled branch"
+	
+this_branch=$(git symbolic-ref HEAD | cut -b 12-)
+
+# Use a detached head so that this operation can be aborted
+git checkout -q $(git rev-parse HEAD)
+
+unmerge=$(git log --pretty=oneline "$base_rev".."$name" | cut -b -40 | tr '\n' ' ')
+while [ -n "$unmerge" ]; do
+	commit="${unmerge%% *}"
+	unmerge="${unmerge#* }"
+	[ -n "$unmerge" ] || break # skip initial .top* commit
+	if ! git revert --no-edit $commit; then
+		info "Please commit merge resolution and call: tg undepend $name"
+		info "It is also safe to abort this operation using:"
+		info "git reset --hard some_branch"
+		info "(You are on a detached HEAD now.)"
+		exit 1
+	fi
+done
+
+git branch -m $this_branch work/$this_branch.save-undepend
+git checkout -q -b work/$this_branch.undepend
+git branch -m work/$this_branch.undepend $this_branch
+git branch -D work/$this_branch.save-undepend
+
+mv .topdeps .topdeps~ && grep -v "^$name\$" .topdeps~ > .topdeps && rm .topdeps~
+git commit -am "Remove dependency on $name."
+
+# Local Variables:
+# sh-basic-offset:8
+# End:
-- 
1.6.0.rc0.44.g67270


-- 
Jan Nieuwenhuizen <janneke@gnu.org> | GNU LilyPond - The music typesetter
http://www.xs4all.nl/~jantien       | http://www.lilypond.org