diff mbox series

[2/7] subtree: exclude commits predating add from recursive processing

Message ID 87af5a316a2ca75e28fda466a04c27bdb02b96b2.1589176201.git.gitgitgadget@gmail.com (mailing list archive)
State New, archived
Headers show
Series subtree: Fix handling of complex history | expand

Commit Message

John Cai via GitGitGadget May 11, 2020, 5:49 a.m. UTC 
From: Tom Clarkson <tom@tqclarkson.com>

Include recursion depth in debug logs so we can see when the recursion is
getting out of hand.

Making the cache handle null mappings correctly and adding older commits
to the cache allows the recursive algorithm to terminate at any point on
mainline rather than needing to reach either the add point or the initial
commit.

Signed-off-by: Tom Clarkson <tom@tqclarkson.com>
---
 contrib/subtree/git-subtree.sh | 37 +++++++++++++++++++++++++++++++---
 1 file changed, 34 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh
index 9867718503c..da0eede6979 100755
--- a/contrib/subtree/git-subtree.sh
+++ b/contrib/subtree/git-subtree.sh
@@ -244,7 +244,7 @@  check_parents () {
 	do
 		if ! test -r "$cachedir/notree/$miss"
 		then
-			debug "  incorrect order: $miss"
+			debug "  unprocessed parent commit: $miss ($indent)"
 			process_split_commit "$miss" "" "$indent"
 		fi
 	done
@@ -392,6 +392,26 @@  find_existing_splits () {
 	done
 }
 
+find_mainline_ref () {
+	debug "Looking for first split..."
+	dir="$1"
+	revs="$2"
+	main=
+	sub=
+	local grep_format="^git-subtree-dir: $dir/*\$"
+	git log --reverse --grep="$grep_format" \
+		--no-show-signature --pretty=format:'START %H%n%s%n%n%b%nEND%n' $revs |
+	while read a b junk
+	do
+		case "$a" in
+		git-subtree-mainline:)
+			echo "$b"
+			return
+			;;
+		esac
+	done
+}
+
 copy_commit () {
 	# We're going to set some environment vars here, so
 	# do it in a subshell to get rid of them safely later
@@ -646,9 +666,9 @@  process_split_commit () {
 
 	progress "$revcount/$revmax ($createcount) [$extracount]"
 
-	debug "Processing commit: $rev"
+	debug "Processing commit: $rev ($indent)"
 	exists=$(cache_get "$rev")
-	if test -n "$exists"
+	if test -z "$(cache_miss "$rev")"
 	then
 		debug "  prior: $exists"
 		return
@@ -773,6 +793,17 @@  cmd_split () {
 
 	unrevs="$(find_existing_splits "$dir" "$revs")"
 
+	mainline="$(find_mainline_ref "$dir" "$revs")"
+	if test -n "$mainline"
+	then
+		debug "Mainline $mainline predates subtree add"
+		git rev-list --topo-order --skip=1 $mainline |
+		while read rev
+		do
+			cache_set "$rev" ""
+		done || exit $?
+	fi
+
 	# We can't restrict rev-list to only $dir here, because some of our
 	# parents have the $dir contents the root, and those won't match.
 	# (and rev-list --follow doesn't seem to solve this)