[PATCH] git-prompt.sh: shorter equal upstream branch name

From: Julien Carsique <redacted>

When using the "name" option of GIT_PS1_SHOWUPSTREAM to show the upstream
abbrev name, if the upstream name is the same as the local name, then some
space could be saved in the prompt. This is especially needed on long branch
names.

Replace the upstream name with the sign '=' if equal to the local one.
Example:    [master * u= origin/=]$
instead of: [master * u= origin/master]$

Signed-off-by: Julien Carsique <redacted>
---
 contrib/completion/git-prompt.sh | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index c5473dc..a9aba20 100644
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh

@@ -209,6 +209,13 @@ __git_ps1_show_upstream ()
 		if [[ -n "$count" && -n "$name" ]]; then
 			__git_ps1_upstream_name=$(git rev-parse \
 				--abbrev-ref "$upstream" 2>/dev/null)
+
+			__head=${b##refs/heads/}
+			if [ "$__head" = "${__git_ps1_upstream_name##*/}" ]; then
+				__git_ps1_upstream_name=${__git_ps1_upstream_name/$__head/=}
+			fi
+			unset __head
+
 			if [ $pcmode = yes ] && [ $ps1_expanded = yes ]; then
 				p="$p \${__git_ps1_upstream_name}"
 			else

-- 
2.1.0