bash prompt: use bash builtins to find out current branch

diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index bc402f56b223a4b96fa378674412eac47ee3b3b3..c2050b69bb9bf1830868b6b0c9ffdf53a52e1ef0 100644 (file)
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh
@@ -355,25 +355,40 @@ __git_ps1 ()
                        r="|BISECTING"
                fi
 
-               test -n "$b" ||
-               b="$(git symbolic-ref HEAD 2>/dev/null)" || {
-                       detached=yes
-                       b="$(
-                       case "${GIT_PS1_DESCRIBE_STYLE-}" in
-                       (contains)
-                               git describe --contains HEAD ;;
-                       (branch)
-                               git describe --contains --all HEAD ;;
-                       (describe)
-                               git describe HEAD ;;
-                       (* | default)
-                               git describe --tags --exact-match HEAD ;;
-                       esac 2>/dev/null)" ||
+               if [ -n "$b" ]; then
+                       :
+               elif [ -h "$g/HEAD" ]; then
+                       # symlink symbolic ref
+                       b="$(git symbolic-ref HEAD 2>/dev/null)"
+               else
+                       local head=""
+                       if ! read head 2>/dev/null <"$g/HEAD"; then
+                               if [ $pcmode = yes ]; then
+                                       PS1="$ps1pc_start$ps1pc_end"
+                               fi
+                               return
+                       fi
+                       # is it a symbolic ref?
+                       b="${head#ref: }"
+                       if [ "$head" = "$b" ]; then
+                               detached=yes
+                               b="$(
+                               case "${GIT_PS1_DESCRIBE_STYLE-}" in
+                               (contains)
+                                       git describe --contains HEAD ;;
+                               (branch)
+                                       git describe --contains --all HEAD ;;
+                               (describe)
+                                       git describe HEAD ;;
+                               (* | default)
+                                       git describe --tags --exact-match HEAD ;;
+                               esac 2>/dev/null)" ||
 
-                       b="$(git rev-parse --short HEAD 2>/dev/null)..." ||
-                       b="unknown"
-                       b="($b)"
-               }
+                               b="$(git rev-parse --short HEAD 2>/dev/null)..." ||
+                               b="unknown"
+                               b="($b)"
+                       fi
+               fi
        fi
 
        if [ -n "$step" ] && [ -n "$total" ]; then