builder: skip checkout if already on the target branch

this avoids poisoning git reflog with entries

diff --git a/builder.sh b/builder.sh
index e903fc6dc1c3ab3aebf4cdbbf7400da4c68aae0a..7d11e10d605ec7c42749c5e861b081bc5f3b020a 100755 (executable)
--- a/builder.sh
+++ b/builder.sh
@@ -1050,7 +1050,10 @@ get_spec() {
 
        if [ -n "$CVSTAG" ]; then
                if git rev-parse --verify -q "$CVSTAG" >/dev/null; then
-                       git checkout "$CVSTAG" --
+                       # checkout only if differs, so this will not trash git reflog
+                       if [ $(git rev-parse "$CVSTAG") != $(git rev-parse HEAD) ]; then
+                               git checkout "$CVSTAG" --
+                       fi
                elif git rev-parse --verify -q "refs/remotes/${REMOTE_PLD}/$CVSTAG"; then
                        git checkout -t "refs/remotes/${REMOTE_PLD}/$CVSTAG" > /dev/null
                fi