Uniform iterators for trees, index, and workdir

This create a new git_iterator type of object that provides a
uniform interface for iterating over the index, an arbitrary
tree, or the working directory of a repository.

As part of this, git ignore support was extended to support
push and pop of directory-based ignore files as the working
directory is being traversed (so the array of ignores does
not have to be recreated at each directory during traveral).

There are a number of other small utility functions in buffer,
path, vector, and fileops that are included in this patch
that made the iterator implementation cleaner.

3 files changed, 388 insertions, 0 deletions

diff --git a/tests-clar/diff/diff_helpers.c b/tests-clar/diff/diff_helpers.c
new file mode 100644
index 00000000..b2dbe9ee
--- /dev/null
+++ b/tests-clar/diff/diff_helpers.c
@@ -0,0 +1,22 @@
+#include "clar_libgit2.h"
+#include "diff_helpers.h"
+
+git_tree *resolve_commit_oid_to_tree(
+	git_repository *repo,
+	const char *partial_oid)
+{
+	size_t len = strlen(partial_oid);
+	git_oid oid;
+	git_object *obj;
+	git_tree *tree;
+
+	if (git_oid_fromstrn(&oid, partial_oid, len) == 0)
+		git_object_lookup_prefix(&obj, repo, &oid, len, GIT_OBJ_ANY);
+	cl_assert(obj);
+	if (git_object_type(obj) == GIT_OBJ_TREE)
+		return (git_tree *)obj;
+	cl_assert(git_object_type(obj) == GIT_OBJ_COMMIT);
+	cl_git_pass(git_commit_tree(&tree, (git_commit *)obj));
+	git_object_free(obj);
+	return tree;
+}
diff --git a/tests-clar/diff/diff_helpers.h b/tests-clar/diff/diff_helpers.h
new file mode 100644
index 00000000..a75dd912
--- /dev/null
+++ b/tests-clar/diff/diff_helpers.h
@@ -0,0 +1,4 @@
+#include "fileops.h"
+
+extern git_tree *resolve_commit_oid_to_tree(
+	git_repository *repo, const char *partial_oid);
diff --git a/tests-clar/diff/iterator.c b/tests-clar/diff/iterator.c
new file mode 100644
index 00000000..e13e3e2b
--- /dev/null
+++ b/tests-clar/diff/iterator.c
@@ -0,0 +1,362 @@
+#include "clar_libgit2.h"
+#include "diff_helpers.h"
+#include "iterator.h"
+
+static git_repository *g_repo = NULL;
+static const char *g_sandbox = NULL;
+
+static void setup_sandbox(const char *sandbox)
+{
+	cl_fixture_sandbox(sandbox);
+	g_sandbox = sandbox;
+
+	p_chdir(sandbox);
+	cl_git_pass(p_rename(".gitted", ".git"));
+	if (p_access("gitattributes", F_OK) == 0)
+		cl_git_pass(p_rename("gitattributes", ".gitattributes"));
+	if (p_access("gitignore", F_OK) == 0)
+		cl_git_pass(p_rename("gitignore", ".gitignore"));
+	p_chdir("..");
+
+	cl_git_pass(git_repository_open(&g_repo, sandbox));
+}
+
+static void cleanup_sandbox(void)
+{
+	if (g_repo) {
+		git_repository_free(g_repo);
+		g_repo = NULL;
+	}
+	if (g_sandbox) {
+		cl_fixture_cleanup(g_sandbox);
+		g_sandbox = NULL;
+	}
+}
+
+void test_diff_iterator__initialize(void)
+{
+	/* since we are doing tests with different sandboxes, defer setup
+	 * to the actual tests.  cleanup will still be done in the global
+	 * cleanup function so that assertion failures don't result in a
+	 * missed cleanup.
+	 */
+}
+
+void test_diff_iterator__cleanup(void)
+{
+	cleanup_sandbox();
+}
+
+
+/* -- TREE ITERATOR TESTS -- */
+
+static void tree_iterator_test(
+	const char *sandbox,
+	const char *treeish,
+	int expected_count,
+	const char **expected_values)
+{
+	git_tree *t;
+	git_iterator *i;
+	const git_index_entry *entry;
+	int count = 0;
+
+	setup_sandbox(sandbox);
+
+	cl_assert(t = resolve_commit_oid_to_tree(g_repo, treeish));
+	cl_git_pass(git_iterator_for_tree(g_repo, t, &i));
+	cl_git_pass(git_iterator_current(i, &entry));
+
+	while (entry != NULL) {
+		if (expected_values != NULL)
+			cl_assert_strequal(expected_values[count], entry->path);
+
+		count++;
+
+		cl_git_pass(git_iterator_advance(i));
+		cl_git_pass(git_iterator_current(i, &entry));
+	}
+
+	git_iterator_free(i);
+
+	cl_assert(expected_count == count);
+
+	git_tree_free(t);
+}
+
+/* results of: git ls-tree -r --name-only 605812a */
+const char *expected_tree_0[] = {
+	".gitattributes",
+	"attr0",
+	"attr1",
+	"attr2",
+	"attr3",
+	"binfile",
+	"macro_test",
+	"root_test1",
+	"root_test2",
+	"root_test3",
+	"root_test4.txt",
+	"subdir/.gitattributes",
+	"subdir/abc",
+	"subdir/subdir_test1",
+	"subdir/subdir_test2.txt",
+	"subdir2/subdir2_test1",
+	NULL
+};
+
+void test_diff_iterator__tree_0(void)
+{
+	tree_iterator_test("attr", "605812a", 16, expected_tree_0);
+}
+
+/* results of: git ls-tree -r --name-only 6bab5c79 */
+const char *expected_tree_1[] = {
+	".gitattributes",
+	"attr0",
+	"attr1",
+	"attr2",
+	"attr3",
+	"root_test1",
+	"root_test2",
+	"root_test3",
+	"root_test4.txt",
+	"subdir/.gitattributes",
+	"subdir/subdir_test1",
+	"subdir/subdir_test2.txt",
+	"subdir2/subdir2_test1",
+	NULL
+};
+
+void test_diff_iterator__tree_1(void)
+{
+	tree_iterator_test("attr", "6bab5c79cd5", 13, expected_tree_1);
+}
+
+/* results of: git ls-tree -r --name-only 26a125ee1 */
+const char *expected_tree_2[] = {
+	"current_file",
+	"file_deleted",
+	"modified_file",
+	"staged_changes",
+	"staged_changes_file_deleted",
+	"staged_changes_modified_file",
+	"staged_delete_file_deleted",
+	"staged_delete_modified_file",
+	"subdir.txt",
+	"subdir/current_file",
+	"subdir/deleted_file",
+	"subdir/modified_file",
+	NULL
+};
+
+void test_diff_iterator__tree_2(void)
+{
+	tree_iterator_test("status", "26a125ee1", 12, expected_tree_2);
+}
+
+/* $ git ls-tree -r --name-only 0017bd4ab1e */
+const char *expected_tree_3[] = {
+	"current_file",
+	"file_deleted",
+	"modified_file",
+	"staged_changes",
+	"staged_changes_file_deleted",
+	"staged_changes_modified_file",
+	"staged_delete_file_deleted",
+	"staged_delete_modified_file"
+};
+
+void test_diff_iterator__tree_3(void)
+{
+	tree_iterator_test("status", "0017bd4ab1e", 8, expected_tree_3);
+}
+
+
+/* -- INDEX ITERATOR TESTS -- */
+
+static void index_iterator_test(
+	const char *sandbox,
+	int expected_count,
+	const char **expected_names,
+	const char **expected_oids)
+{
+	git_iterator *i;
+	const git_index_entry *entry;
+	int count = 0;
+
+	setup_sandbox(sandbox);
+
+	cl_git_pass(git_iterator_for_index(g_repo, &i));
+	cl_git_pass(git_iterator_current(i, &entry));
+
+	while (entry != NULL) {
+		if (expected_names != NULL)
+			cl_assert_strequal(expected_names[count], entry->path);
+
+		if (expected_oids != NULL) {
+			git_oid oid;
+			cl_git_pass(git_oid_fromstr(&oid, expected_oids[count]));
+			cl_assert(git_oid_cmp(&oid, &entry->oid) == 0);
+		}
+
+		count++;
+		cl_git_pass(git_iterator_advance(i));
+		cl_git_pass(git_iterator_current(i, &entry));
+	}
+
+	git_iterator_free(i);
+
+	cl_assert(count == expected_count);
+}
+
+static const char *expected_index_0[] = {
+	"attr0",
+	"attr1",
+	"attr2",
+	"attr3",
+	"binfile",
+	"gitattributes",
+	"macro_bad",
+	"macro_test",
+	"root_test1",
+	"root_test2",
+	"root_test3",
+	"root_test4.txt",
+	"subdir/.gitattributes",
+	"subdir/abc",
+	"subdir/subdir_test1",
+	"subdir/subdir_test2.txt",
+	"subdir2/subdir2_test1",
+};
+
+static const char *expected_index_oids_0[] = {
+	"556f8c827b8e4a02ad5cab77dca2bcb3e226b0b3",
+	"3b74db7ab381105dc0d28f8295a77f6a82989292",
+	"2c66e14f77196ea763fb1e41612c1aa2bc2d8ed2",
+	"c485abe35abd4aa6fd83b076a78bbea9e2e7e06c",
+	"d800886d9c86731ae5c4a62b0b77c437015e00d2",
+	"2b40c5aca159b04ea8d20ffe36cdf8b09369b14a",
+	"5819a185d77b03325aaf87cafc771db36f6ddca7",
+	"ff69f8639ce2e6010b3f33a74160aad98b48da2b",
+	"45141a79a77842c59a63229403220a4e4be74e3d",
+	"45141a79a77842c59a63229403220a4e4be74e3d",
+	"45141a79a77842c59a63229403220a4e4be74e3d",
+	"fb5067b1aef3ac1ada4b379dbcb7d17255df7d78",
+	"99eae476896f4907224978b88e5ecaa6c5bb67a9",
+	"3e42ffc54a663f9401cc25843d6c0e71a33e4249",
+	"e563cf4758f0d646f1b14b76016aa17fa9e549a4",
+	"fb5067b1aef3ac1ada4b379dbcb7d17255df7d78",
+	"dccada462d3df8ac6de596fb8c896aba9344f941"
+};
+
+void test_diff_iterator__index_0(void)
+{
+	index_iterator_test("attr", 17, expected_index_0, expected_index_oids_0);
+}
+
+static const char *expected_index_1[] = {
+	"current_file",
+	"file_deleted",
+	"modified_file",
+	"staged_changes",
+	"staged_changes_file_deleted",
+	"staged_changes_modified_file",
+	"staged_new_file",
+	"staged_new_file_deleted_file",
+	"staged_new_file_modified_file",
+	"subdir.txt",
+	"subdir/current_file",
+	"subdir/deleted_file",
+	"subdir/modified_file",
+};
+
+static const char* expected_index_oids_1[] = {
+	"a0de7e0ac200c489c41c59dfa910154a70264e6e",
+	"5452d32f1dd538eb0405e8a83cc185f79e25e80f",
+	"452e4244b5d083ddf0460acf1ecc74db9dcfa11a",
+	"55d316c9ba708999f1918e9677d01dfcae69c6b9",
+	"a6be623522ce87a1d862128ac42672604f7b468b",
+	"906ee7711f4f4928ddcb2a5f8fbc500deba0d2a8",
+	"529a16e8e762d4acb7b9636ff540a00831f9155a",
+	"90b8c29d8ba39434d1c63e1b093daaa26e5bd972",
+	"ed062903b8f6f3dccb2fa81117ba6590944ef9bd",
+	"e8ee89e15bbe9b20137715232387b3de5b28972e",
+	"53ace0d1cc1145a5f4fe4f78a186a60263190733",
+	"1888c805345ba265b0ee9449b8877b6064592058",
+	"a6191982709b746d5650e93c2acf34ef74e11504"
+};
+
+void test_diff_iterator__index_1(void)
+{
+	index_iterator_test("status", 13, expected_index_1, expected_index_oids_1);
+}
+
+
+/* -- WORKDIR ITERATOR TESTS -- */
+
+static void workdir_iterator_test(
+	const char *sandbox,
+	int expected_count,
+	int expected_ignores,
+	const char **expected_names,
+	const char *an_ignored_name)
+{
+	git_iterator *i;
+	const git_index_entry *entry;
+	int count = 0, count_all = 0;
+
+	setup_sandbox(sandbox);
+
+	cl_git_pass(git_iterator_for_workdir(g_repo, &i));
+	cl_git_pass(git_iterator_current(i, &entry));
+
+	while (entry != NULL) {
+		int ignored = git_iterator_current_is_ignored(i);
+
+		if (expected_names != NULL)
+			cl_assert_strequal(expected_names[count_all], entry->path);
+
+		if (an_ignored_name && strcmp(an_ignored_name,entry->path)==0)
+			cl_assert(ignored);
+
+		if (!ignored)
+			count++;
+		count_all++;
+
+		cl_git_pass(git_iterator_advance(i));
+		cl_git_pass(git_iterator_current(i, &entry));
+	}
+
+	git_iterator_free(i);
+
+	cl_assert(count == expected_count);
+	cl_assert(count_all == expected_count + expected_ignores);
+}
+
+void test_diff_iterator__workdir_0(void)
+{
+	workdir_iterator_test("attr", 15, 4, NULL, "ign");
+}
+
+static const char *status_paths[] = {
+	"current_file",
+	"ignored_file",
+	"modified_file",
+	"new_file",
+	"staged_changes",
+	"staged_changes_modified_file",
+	"staged_delete_modified_file",
+	"staged_new_file",
+	"staged_new_file_modified_file",
+	"subdir/current_file",
+	"subdir/modified_file",
+	"subdir/new_file",
+	"subdir.txt",
+	NULL
+};
+
+void test_diff_iterator__workdir_1(void)
+{
+	workdir_iterator_test("status", 12, 1, status_paths, "ignored_file");
+}