diff-index: report unmerged new entries

Since an earlier change to diff-index by d1f2d7e (Make run_diff_index()
use unpack_trees(), not read_tree(), 2008-01-19), we stopped reporting an
unmerged path that does not exist in the tree, but we should.

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

diff-lib.c

@@ -348,8 +348,8 @@ static void do_oneway_diff(struct unpack_trees_options *o,
 	match_missing = !revs->ignore_merges;
 
 	if (cached && idx && ce_stage(idx)) {
-		if (tree)
-			diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode, idx->sha1);
+		diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode,
+			     idx->sha1);
 		return;
 	}
 

t/t7060-wtstatus.sh

@@ -0,0 +1,31 @@
+#!/bin/sh
+
+test_description='basic work tree status reporting'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+	test_commit A &&
+	test_commit B oneside added &&
+	git checkout A^0 &&
+	test_commit C oneside created
+'
+
+test_expect_success 'A/A conflict' '
+	git checkout B^0 &&
+	test_must_fail git merge C
+'
+
+test_expect_success 'Report path with conflict' '
+	git diff --cached --name-status >actual &&
+	echo "U	oneside" >expect &&
+	test_cmp expect actual
+'
+
+test_expect_success 'Report new path with conflict' '
+	git diff --cached --name-status HEAD^ >actual &&
+	echo "U	oneside" >expect &&
+	test_cmp expect actual
+'
+
+test_done