1 files changed, 82 insertions, 0 deletions
diff --git a/t/t4054-diff-bogus-tree.sh b/t/t4054-diff-bogus-tree.sh
new file mode 100755
index 0000000000..8c95f152b2
--- /dev/null
+++ b/t/t4054-diff-bogus-tree.sh
@@ -0,0 +1,82 @@
+#!/bin/sh
+
+test_description='test diff with a bogus tree containing the null sha1'
+. ./test-lib.sh
+
+test_expect_success 'create bogus tree' '
+	name=$(echo $ZERO_OID | sed -e "s/00/Q/g") &&
+	bogus_tree=$(
+		printf "100644 fooQ$name" |
+		q_to_nul |
+		git hash-object -w --stdin -t tree
+	)
+'
+
+test_expect_success 'create tree with matching file' '
+	echo bar >foo &&
+	git add foo &&
+	good_tree=$(git write-tree) &&
+	blob=$(git rev-parse :foo)
+'
+
+test_expect_success 'raw diff shows null sha1 (addition)' '
+	echo ":000000 100644 $ZERO_OID $ZERO_OID A	foo" >expect &&
+	git diff-tree $EMPTY_TREE $bogus_tree >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'raw diff shows null sha1 (removal)' '
+	echo ":100644 000000 $ZERO_OID $ZERO_OID D	foo" >expect &&
+	git diff-tree $bogus_tree $EMPTY_TREE >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'raw diff shows null sha1 (modification)' '
+	echo ":100644 100644 $blob $ZERO_OID M	foo" >expect &&
+	git diff-tree $good_tree $bogus_tree >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'raw diff shows null sha1 (other direction)' '
+	echo ":100644 100644 $ZERO_OID $blob M	foo" >expect &&
+	git diff-tree $bogus_tree $good_tree >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'raw diff shows null sha1 (reverse)' '
+	echo ":100644 100644 $ZERO_OID $blob M	foo" >expect &&
+	git diff-tree -R $good_tree $bogus_tree >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'raw diff shows null sha1 (index)' '
+	echo ":100644 100644 $ZERO_OID $blob M	foo" >expect &&
+	git diff-index $bogus_tree >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'patch fails due to bogus sha1 (addition)' '
+	test_must_fail git diff-tree -p $EMPTY_TREE $bogus_tree
+'
+
+test_expect_success 'patch fails due to bogus sha1 (removal)' '
+	test_must_fail git diff-tree -p $bogus_tree $EMPTY_TREE
+'
+
+test_expect_success 'patch fails due to bogus sha1 (modification)' '
+	test_must_fail git diff-tree -p $good_tree $bogus_tree
+'
+
+test_expect_success 'patch fails due to bogus sha1 (other direction)' '
+	test_must_fail git diff-tree -p $bogus_tree $good_tree
+'
+
+test_expect_success 'patch fails due to bogus sha1 (reverse)' '
+	test_must_fail git diff-tree -R -p $good_tree $bogus_tree
+'
+
+test_expect_success 'patch fails due to bogus sha1 (index)' '
+	test_must_fail git diff-index -p $bogus_tree
+'
+
+test_done