Trim some extra merge commits that don't need to go into the split tree.

diff --git a/git-subtree.sh b/git-subtree.sh
index 19ac2ef1c14aec87c9e91eb175e0319aab60122c..ffd3e0b865f5d12a42428e80c03f6272931ce878 100755 (executable)
--- a/git-subtree.sh
+++ b/git-subtree.sh
@@ -168,6 +168,7 @@ copy_commit()
 {
        # We're doing to set some environment vars here, so
        # do it in a subshell to get rid of them safely later
+       debug copy_commit "{$1}" "{$2}" "{$3}"
        git log -1 --pretty=format:'%an%n%ae%n%ad%n%cn%n%ce%n%cd%n%s%n%n%b' "$1" |
        (
                read GIT_AUTHOR_NAME
@@ -258,19 +259,31 @@ copy_or_skip()
 
        identical=
        p=
+       gotparents=
        for parent in $newparents; do
                ptree=$(toptree_for_commit $parent) || exit $?
+               [ -z "$ptree" ] && continue
                if [ "$ptree" = "$tree" ]; then
                        # an identical parent could be used in place of this rev.
                        identical="$parent"
                fi
-               if [ -n "$ptree" ]; then
-                       parentmatch="$parentmatch$parent"
+               
+               # sometimes both old parents map to the same newparent;
+               # eliminate duplicates
+               is_new=1
+               for gp in $gotparents; do
+                       if [ "$gp" = "$parent" ]; then
+                               is_new=
+                               break
+                       fi
+               done
+               if [ -n "$is_new" ]; then
+                       gotparents="$gotparents $parent"
                        p="$p -p $parent"
                fi
        done
        
-       if [ -n "$identical" -a "$parentmatch" = "$identical" ]; then
+       if [ -n "$identical" -a "$gotparents" = " $identical" ]; then
                echo $identical
        else
                copy_commit $rev $tree "$p" || exit $?