add merge.renamelimit config option

The point of rename limiting is to bound the amount of time
we spend figuring out inexact renames. Currently we use a
single value, diff.renamelimit, for all situations. However,
it is probably the case that a user is willing to spend more
time finding renames during a merge than they are while
looking at git-log.

This patch provides a way of setting those values separately
(though for backwards compatibility, merge still falls back
on the diff renamelimit).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/t/t6032-merge-large-rename.sh b/t/t6032-merge-large-rename.sh
new file mode 100755
index 0000000000..eac5ebac24
--- /dev/null
+++ b/t/t6032-merge-large-rename.sh
@@ -0,0 +1,73 @@
+#!/bin/sh
+
+test_description='merging with large rename matrix'
+. ./test-lib.sh
+
+count() {
+	i=1
+	while test $i -le $1; do
+		echo $i
+		i=$(($i + 1))
+	done
+}
+
+test_expect_success 'setup (initial)' '
+	touch file &&
+	git add . &&
+	git commit -m initial &&
+	git tag initial
+'
+
+make_text() {
+	echo $1: $2
+	for i in `count 20`; do
+		echo $1: $i
+	done
+	echo $1: $3
+}
+
+test_rename() {
+	test_expect_success "rename ($1, $2)" '
+	n='$1'
+	expect='$2'
+	git checkout -f master &&
+	git branch -D test$n || true &&
+	git reset --hard initial &&
+	for i in $(count $n); do
+		make_text $i initial initial >$i
+	done &&
+	git add . &&
+	git commit -m add=$n &&
+	for i in $(count $n); do
+		make_text $i changed initial >$i
+	done &&
+	git commit -a -m change=$n &&
+	git checkout -b test$n HEAD^ &&
+	for i in $(count $n); do
+		git rm $i
+		make_text $i initial changed >$i.moved
+	done &&
+	git add . &&
+	git commit -m change+rename=$n &&
+	case "$expect" in
+		ok) git merge master ;;
+		 *) test_must_fail git merge master ;;
+	esac
+	'
+}
+
+test_rename 5 ok
+
+test_expect_success 'set diff.renamelimit to 4' '
+	git config diff.renamelimit 4
+'
+test_rename 4 ok
+test_rename 5 fail
+
+test_expect_success 'set merge.renamelimit to 5' '
+	git config merge.renamelimit 5
+'
+test_rename 5 ok
+test_rename 6 fail
+
+test_done