resolve-undo: basic tests

Make sure that resolving a failed merge with git add records
the conflicted state, committing the result keeps that state,
and checking out another commit clears the state.

"git ls-files" learns a new option --resolve-undo to show the
recorded information.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 88 insertions, 0 deletions

diff --git a/t/t2030-unresolve-info.sh b/t/t2030-unresolve-info.sh
new file mode 100755
index 0000000000..785c8b3fca
--- /dev/null
+++ b/t/t2030-unresolve-info.sh
@@ -0,0 +1,88 @@
+#!/bin/sh
+
+test_description='undoing resolution'
+
+. ./test-lib.sh
+
+check_resolve_undo () {
+	msg=$1
+	shift
+	while case $# in
+	0)	break ;;
+	1|2|3)	die "Bug in check-resolve-undo test" ;;
+	esac
+	do
+		path=$1
+		shift
+		for stage in 1 2 3
+		do
+			sha1=$1
+			shift
+			case "$sha1" in
+			'') continue ;;
+			esac
+			sha1=$(git rev-parse --verify "$sha1")
+			printf "100644 %s %s\t%s\n" $sha1 $stage $path
+		done
+	done >"$msg.expect" &&
+	git ls-files --resolve-undo >"$msg.actual" &&
+	test_cmp "$msg.expect" "$msg.actual"
+}
+
+prime_resolve_undo () {
+	git reset --hard &&
+	git checkout second^0 &&
+	test_tick &&
+	test_must_fail git merge third^0 &&
+	echo merge does not leave anything &&
+	check_resolve_undo empty &&
+	echo different >file &&
+	git add file &&
+	echo resolving records &&
+	check_resolve_undo recorded file initial:file second:file third:file
+}
+
+test_expect_success setup '
+	test_commit initial file first &&
+	git branch side &&
+	git branch another &&
+	test_commit second file second &&
+	git checkout side &&
+	test_commit third file third &&
+	git checkout another &&
+	test_commit fourth file fourth &&
+	git checkout master
+'
+
+test_expect_success 'add records switch clears' '
+	prime_resolve_undo &&
+	test_tick &&
+	git commit -m merged &&
+	echo committing keeps &&
+	check_resolve_undo kept file initial:file second:file third:file &&
+	git checkout second^0 &&
+	echo switching clears &&
+	check_resolve_undo cleared
+'
+
+test_expect_success 'rm records reset clears' '
+	prime_resolve_undo &&
+	test_tick &&
+	git commit -m merged &&
+	echo committing keeps &&
+	check_resolve_undo kept file initial:file second:file third:file &&
+
+	echo merge clears upfront &&
+	test_must_fail git merge fourth^0 &&
+	check_resolve_undo nuked &&
+
+	git rm -f file &&
+	echo resolving records &&
+	check_resolve_undo recorded file initial:file HEAD:file fourth:file &&
+
+	git reset --hard &&
+	echo resetting discards &&
+	check_resolve_undo discarded
+'
+
+test_done