git-checkout: revert specific paths to either index or a given tree-ish.

diff --git a/git-branch.sh b/git-branch.sh
index 81b9e6cce138452ab50c1dee869b82a9f6706d34..e2db9063d4c63288c5834046962290ff9dfca127 100755 (executable)
--- a/git-branch.sh
+++ b/git-branch.sh
@@ -3,7 +3,7 @@
 . git-sh-setup || die "Not a git archive"
 
 usage () {
-    echo >&2 "usage: $(basename $0)"' [<branchname> [start-point]]
+    echo >&2 "usage: $(basename $0)"' [-d <branch>] | [<branch> [start-point]]
 
 If no arguments, show available branches and mark current branch with a star.
 If one argument, create a new branch <branchname> based off of current HEAD.
@@ -12,9 +12,68 @@ If two arguments, create a new branch <branchname> based off of <start-point>.
     exit 1
 }
 
+delete_branch () {
+    option="$1"
+    shift
+    headref=$(GIT_DIR="$GIT_DIR" git-symbolic-ref HEAD |
+              sed -e 's|^refs/heads/||')
+    for branch_name
+    do
+       case ",$headref," in
+       ",$branch_name,")
+           die "Cannot delete the branch you are on." ;;
+       ,,)
+           die "What branch are you on anyway?" ;;
+       esac
+       branch=$(cat "$GIT_DIR/refs/heads/$branch_name") &&
+           branch=$(git-rev-parse --verify "$branch^0") ||
+               die "Seriously, what branch are you talking about?"
+       case "$option" in
+       -D)
+           ;;
+       *)
+           mbs=$(git-merge-base -a "$branch" HEAD | tr '\012' ' ')
+           case " $mbs " in
+           *' '$branch' '*)
+               # the merge base of branch and HEAD contains branch --
+               # which means that the HEAD contains everything in the HEAD.
+               ;;
+           *)
+               echo >&2 "The branch '$branch_name' is not a strict subset of your current HEAD.
+    If you are sure you want to delete it, run 'git branch -D $branch_name'."
+               exit 1
+               ;;
+           esac
+           ;;
+       esac
+       rm -f "$GIT_DIR/refs/heads/$branch_name"
+       echo "Deleted branch $branch_name."
+    done
+    exit 0
+}
+
+while case "$#,$1" in 0,*) break ;; *,-*) ;; *) break ;; esac
+do
+       case "$1" in
+       -d | -D)
+               delete_branch "$@"
+               exit
+               ;;
+       --)
+               shift
+               break
+               ;;
+       -*)
+               usage
+               ;;
+       esac
+       shift
+done
+
 case "$#" in
 0)
-       headref=$(readlink "$GIT_DIR/HEAD" | sed -e 's|^refs/heads/||')
+       headref=$(GIT_DIR="$GIT_DIR" git-symbolic-ref HEAD |
+                 sed -e 's|^refs/heads/||')
        git-rev-parse --symbolic --all |
        sed -ne 's|^refs/heads/||p' |
        sort |
@@ -36,13 +95,11 @@ case "$#" in
 esac
 branchname="$1"
 
-case "$branchname" in
--*)
-       usage;;
-esac
-
 rev=$(git-rev-parse --verify "$head") || exit
 
-[ -e "$GIT_DIR/refs/heads/$branchname" ] && die "$branchname already exists"
+[ -e "$GIT_DIR/refs/heads/$branchname" ] &&
+       die "$branchname already exists."
+git-check-ref-format "heads/$branchname" ||
+       die "we do not like '$branchname' as a branch name."
 
 echo $rev > "$GIT_DIR/refs/heads/$branchname"