tests: diff: test parsing diffs with a new file with spaces in its path

Add a test that verifies that we are able to parse patches which add a
new file that has spaces in its path.

tests/diff/parse.c

@@ -359,3 +359,21 @@ void test_diff_parse__lineinfo(void)
 	git_patch_free(patch);
 	git_diff_free(diff);
 }
+
+void test_diff_parse__new_file_with_space(void)
+{
+	const char *content = PATCH_ORIGINAL_NEW_FILE_WITH_SPACE;
+	git_patch *patch;
+	git_diff *diff;
+
+	cl_git_pass(git_diff_from_buffer(&diff, content, strlen(content)));
+	cl_git_pass(git_patch_from_diff((git_patch **) &patch, diff, 0));
+
+	cl_assert_equal_p(patch->diff_opts.old_prefix, NULL);
+	cl_assert_equal_p(patch->delta->old_file.path, NULL);
+	cl_assert_equal_s(patch->diff_opts.new_prefix, "b/");
+	cl_assert_equal_s(patch->delta->new_file.path, "sp ace.txt");
+
+	git_patch_free(patch);
+	git_diff_free(diff);
+}

tests/patch/patch_common.h

@@ -841,3 +841,12 @@
 	"diff --git a/binary.bin b/binary.bin\n" \
 	"index 27184d9..7c94f9e 100644\n" \
 	"Binary files a/binary.bin and b/binary.bin differ\n"
+
+#define PATCH_ORIGINAL_NEW_FILE_WITH_SPACE \
+	"diff --git a/sp ace.txt b/sp ace.txt\n" \
+	"new file mode 100644\n" \
+	"index 000000000..789819226\n" \
+	"--- /dev/null\n" \
+	"+++ b/sp ace.txt\n" \
+	"@@ -0,0 +1 @@\n" \
+	"+a\n"