Even more aggressive commit trimming.

Now we cut out a commit if any of its parents had the same tree; just use
that parent in its place.  This makes the history look nice, but I don't
think it's quite right...

diff --git a/git-subtree.sh b/git-subtree.sh
index e6d8ce8817d39a813c44bf46d6810ff110690128..03107e2251c35e0f31e4e29ab9f0fb5515079ced 100755 (executable)
--- a/git-subtree.sh
+++ b/git-subtree.sh
@@ -202,6 +202,29 @@ tree_changed()
        fi
 }
 
+copy_or_skip()
+{
+       rev="$1"
+       tree="$2"
+       newparents="$3"
+       assert [ -n "$tree" ]
+
+       p=""
+       for parent in $newparents; do
+               ptree=$(toptree_for_commit $parent) || exit $?
+               if [ "$ptree" = "$tree" ]; then
+                       # any identical parent means this commit is unnecessary
+                       echo $parent
+                       return 0
+               elif [ -n "$ptree" ]; then
+                       # an existing, non-identical parent is important
+                       p="$p -p $parent"
+               fi
+       done
+       
+       copy_commit $rev $tree "$p" || exit $?
+}
+
 cmd_split()
 {
        debug "Splitting $dir..."
@@ -238,16 +261,7 @@ cmd_split()
                debug "  tree is: $tree"
                [ -z $tree ] && continue
 
-               p=""
-               for parent in $newparents; do
-                       p="$p -p $parent"
-               done
-                       
-               if tree_changed $tree $newparents; then
-                       newrev=$(copy_commit $rev $tree "$p") || exit $?
-               else
-                       newrev="$newparents"
-               fi
+               newrev=$(copy_or_skip "$rev" "$tree" "$newparents") || exit $?
                debug "  newrev is: $newrev"
                cache_set $rev $newrev
                cache_set latest_new $newrev

diff --git a/test.sh b/test.sh
index 8a9d92f7038c9bda4d1456b75397ebbfd766253e..a8ed0dbc7d9b927ddb12d7e42c925ce12867a68d 100755 (executable)
--- a/test.sh
+++ b/test.sh
@@ -93,4 +93,4 @@ git branch subproj-merge-split3
 cd ../mainline
 git fetch ../subproj subproj-merge-split3
 git branch subproj-merge-split3 FETCH_HEAD
-git merge subproj-merge-split3
+git merge -s subtree subproj-merge-split3