X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=topgit.git;a=blobdiff_plain;f=tg-depend.sh;h=474ccda4e098a2046a2e60a52d5addad4b007f81;hp=498eec4e3e0018c0d57c6f24ee788e7e13aaf48c;hb=8d92943bcdb6eea3819dce28d2ff48dd8a061b31;hpb=bb4aa31cb1b1f107302216ee9a6ce36bb31bd7cf

diff --git a/tg-depend.sh b/tg-depend.sh
index 498eec4..474ccda 100644
--- a/tg-depend.sh
+++ b/tg-depend.sh
@@ -6,21 +6,29 @@
 name=
 
 
+usage()
+{
+    echo "Usage: tg [...] depend add NAME" >&2
+    exit 1
+}
+
 ## Parse options
 
-subcmd="$1"; shift
-[ "$subcmd" = "-h" ] && {
-	echo "Usage: tg [...] depend add NAME" >&2
-	exit 1
-}
-[ "$subcmd" = "add" ] || die "unknown subcommand ($subcmd)"
+subcmd="$1"; shift || :
+case "$subcmd" in
+	-h|"")
+		usage;;
+	add)
+		;;
+	*)
+		die "unknown subcommand ($subcmd)";;
+esac
 
 while [ -n "$1" ]; do
 	arg="$1"; shift
 	case "$arg" in
 	-*)
-		echo "Usage: tg [...] depend add NAME" >&2
-		exit 1;;
+		usage;;
 	*)
 		[ -z "$name" ] || die "name already specified ($name)"
 		name="$arg";;
@@ -33,13 +41,31 @@ done
 [ -n "$name" ] || die "no branch name specified"
 branchrev="$(git rev-parse --verify "$name" 2>/dev/null)" ||
 	die "invalid branch name: $name"
-baserev="$(git rev-parse --verify "refs/top-bases/$name" 2>/dev/null)" ||
-	die "not a TopGit topic branch: $name"
 
+# Check that we are on a TopGit branch.
+current_name="$(git symbolic-ref HEAD | sed 's#^refs/\(heads\|top-bases\)/##')"
+current_base_rev="$(git rev-parse --short --verify "refs/top-bases/$current_name" 2>/dev/null)" ||
+	die "not a TopGit-controlled branch"
 
 ## Record new dependency
+depend_add()
+{
+	[ "$name" = "$current_name" ] &&
+		die "$name cannot depend on itself."
+
+	{ $tg summary --deps; echo "$current_name" "$name"; } |
+		tsort >/dev/null ||
+		die "tg: that dependency would introduce a dependency loop"
+
+	grep -F -x -e "$name" "$root_dir/.topdeps" >/dev/null &&
+		die "tg: $current_name already depends on $name"
+
+	echo "$name" >>"$root_dir/.topdeps"
+	git add -f "$root_dir/.topdeps"
+	git commit -m"New TopGit dependency: $name"
+	$tg update
+}
+
+depend_$subcmd
 
-echo "$name" >>.topdeps
-git add .topdeps
-git commit -m"New TopGit dependency: $name"
-$tg update
+# vim:noet