iterator: test workdir pathlist with deep paths

In the workdir iterator we do some tricky things to step down into
directories to look for things that are in our pathlist.  Make sure
that we don't confuse between folders that we're definitely going to
return everything in and folders that we're only stepping down into
to keep looking for matches.

tests/repo/iterator.c

@@ -1641,6 +1641,165 @@ void test_repo_iterator__workdir_pathlist_with_dirs(void)
 	git_vector_free(&filelist);
 }
 
+static void create_paths(const char *root, int depth)
+{
+	git_buf fullpath = GIT_BUF_INIT;
+	size_t root_len;
+	int i;
+
+	cl_git_pass(git_buf_puts(&fullpath, root));
+	cl_git_pass(git_buf_putc(&fullpath, '/'));
+
+	root_len = fullpath.size;
+
+	for (i = 0; i < 8; i++) {
+		bool file = (depth == 0 || (i % 2) == 0);
+		git_buf_truncate(&fullpath, root_len);
+		cl_git_pass(git_buf_printf(&fullpath, "item%d", i));
+
+		if (file) {
+			cl_git_rewritefile(fullpath.ptr, "This is a file!\n");
+		} else {
+			cl_must_pass(p_mkdir(fullpath.ptr, 0777));
+
+			if (depth > 0)
+				create_paths(fullpath.ptr, (depth - 1));
+		}
+	}
+}
+
+void test_repo_iterator__workdir_pathlist_for_deeply_nested_item(void)
+{
+	git_iterator *i;
+	git_iterator_options i_opts = GIT_ITERATOR_OPTIONS_INIT;
+	git_vector filelist;
+
+	cl_git_pass(git_vector_init(&filelist, 5, NULL));
+
+	g_repo = cl_git_sandbox_init("icase");
+	create_paths(git_repository_workdir(g_repo), 3);
+
+	/* Ensure that we find the single path we're interested in, and we find
+	 * it efficiently, and don't stat the entire world to get there.
+	 */
+	{
+		const char *expected[] = { "item1/item3/item5/item7" };
+		size_t expected_len = 1;
+
+		git_vector_clear(&filelist);
+		cl_git_pass(git_vector_insert(&filelist, "item1/item3/item5/item7"));
+
+		i_opts.pathlist.strings = (char **)filelist.contents;
+		i_opts.pathlist.count = filelist.length;
+		i_opts.flags = GIT_ITERATOR_DONT_IGNORE_CASE;
+
+		cl_git_pass(git_iterator_for_workdir(&i, g_repo, NULL, NULL, &i_opts));
+		expect_iterator_items(i, expected_len, expected, expected_len, expected);
+		cl_assert_equal_i(4, i->stat_calls);
+		git_iterator_free(i);
+	}
+
+	/* Ensure that we find the single path we're interested in, and we find
+	 * it efficiently, and don't stat the entire world to get there.
+	 */
+	{
+		const char *expected[] = {
+			"item1/item3/item5/item0", "item1/item3/item5/item1",
+			"item1/item3/item5/item2", "item1/item3/item5/item3",
+			"item1/item3/item5/item4", "item1/item3/item5/item5",
+			"item1/item3/item5/item6", "item1/item3/item5/item7",
+		};
+		size_t expected_len = 8;
+
+		git_vector_clear(&filelist);
+		cl_git_pass(git_vector_insert(&filelist, "item1/item3/item5/"));
+
+		i_opts.pathlist.strings = (char **)filelist.contents;
+		i_opts.pathlist.count = filelist.length;
+		i_opts.flags = GIT_ITERATOR_DONT_IGNORE_CASE;
+
+		cl_git_pass(git_iterator_for_workdir(&i, g_repo, NULL, NULL, &i_opts));
+		expect_iterator_items(i, expected_len, expected, expected_len, expected);
+		cl_assert_equal_i(11, i->stat_calls);
+		git_iterator_free(i);
+	}
+
+	/* Ensure that we find the single path we're interested in, and we find
+	 * it efficiently, and don't stat the entire world to get there.
+	 */
+	{
+		const char *expected[] = {
+			"item1/item3/item0",
+			"item1/item3/item1/item0", "item1/item3/item1/item1",
+			"item1/item3/item1/item2", "item1/item3/item1/item3",
+			"item1/item3/item1/item4", "item1/item3/item1/item5",
+			"item1/item3/item1/item6", "item1/item3/item1/item7",
+			"item1/item3/item2",
+			"item1/item3/item3/item0", "item1/item3/item3/item1",
+			"item1/item3/item3/item2", "item1/item3/item3/item3",
+			"item1/item3/item3/item4", "item1/item3/item3/item5",
+			"item1/item3/item3/item6", "item1/item3/item3/item7",
+			"item1/item3/item4",
+			"item1/item3/item5/item0", "item1/item3/item5/item1",
+			"item1/item3/item5/item2", "item1/item3/item5/item3",
+			"item1/item3/item5/item4", "item1/item3/item5/item5",
+			"item1/item3/item5/item6", "item1/item3/item5/item7",
+			"item1/item3/item6",
+			"item1/item3/item7/item0", "item1/item3/item7/item1",
+			"item1/item3/item7/item2", "item1/item3/item7/item3",
+			"item1/item3/item7/item4", "item1/item3/item7/item5",
+			"item1/item3/item7/item6", "item1/item3/item7/item7",
+		};
+		size_t expected_len = 36;
+
+		git_vector_clear(&filelist);
+		cl_git_pass(git_vector_insert(&filelist, "item1/item3/"));
+
+		i_opts.pathlist.strings = (char **)filelist.contents;
+		i_opts.pathlist.count = filelist.length;
+		i_opts.flags = GIT_ITERATOR_DONT_IGNORE_CASE;
+
+		cl_git_pass(git_iterator_for_workdir(&i, g_repo, NULL, NULL, &i_opts));
+		expect_iterator_items(i, expected_len, expected, expected_len, expected);
+		cl_assert_equal_i(42, i->stat_calls);
+		git_iterator_free(i);
+	}
+
+	/* Ensure that we find the single path we're interested in, and we find
+	 * it efficiently, and don't stat the entire world to get there.
+	 */
+	{
+		const char *expected[] = {
+			"item0", "item1/item2", "item5/item7/item4", "item6",
+			"item7/item3/item1/item6" };
+		size_t expected_len = 5;
+
+		git_vector_clear(&filelist);
+		cl_git_pass(git_vector_insert(&filelist, "item7/item3/item1/item6"));
+		cl_git_pass(git_vector_insert(&filelist, "item6"));
+		cl_git_pass(git_vector_insert(&filelist, "item5/item7/item4"));
+		cl_git_pass(git_vector_insert(&filelist, "item1/item2"));
+		cl_git_pass(git_vector_insert(&filelist, "item0"));
+
+		/* also add some things that don't exist or don't match the right type */
+		cl_git_pass(git_vector_insert(&filelist, "item2/"));
+		cl_git_pass(git_vector_insert(&filelist, "itemN"));
+		cl_git_pass(git_vector_insert(&filelist, "item1/itemA"));
+		cl_git_pass(git_vector_insert(&filelist, "item5/item3/item4/"));
+
+		i_opts.pathlist.strings = (char **)filelist.contents;
+		i_opts.pathlist.count = filelist.length;
+		i_opts.flags = GIT_ITERATOR_DONT_IGNORE_CASE;
+
+		cl_git_pass(git_iterator_for_workdir(&i, g_repo, NULL, NULL, &i_opts));
+		expect_iterator_items(i, expected_len, expected, expected_len, expected);
+		cl_assert_equal_i(14, i->stat_calls);
+		git_iterator_free(i);
+	}
+
+	git_vector_free(&filelist);
+}
+
 void test_repo_iterator__workdir_bounded_submodules(void)
 {
 	git_iterator *i;