Merge pull request #170 from zeux/move

This change implements move ctor and assign support for xml_document.

All node handles remain valid after the move and point to the new document; the only exception is the document node itself (that remains unmoved).

Move is O(document size) in theory because it needs to relocate immediate document children (there is just one in conformant documents) and all memory pages; in practice the memory pages only need the header adjusted, which is ~0.1% of the actual data size.

Move requires no allocations in general, except when using compact mode where some moves need to grow the hash table which can fail (throw).

Fixes #104

1 files changed, 185 insertions, 0 deletions

diff --git a/tests/test_document.cpp b/tests/test_document.cpp
index ecbe6dc..08d836c 100644
--- a/tests/test_document.cpp
+++ b/tests/test_document.cpp
@@ -1621,3 +1621,188 @@ TEST(document_convert_out_of_memory)
 		delete[] files[j].data;
 	}
 }
+
+#ifdef PUGIXML_HAS_MOVE
+TEST_XML(document_move_ctor, "<node1/><node2/>")
+{
+	xml_document other = std::move(doc);
+
+	CHECK(doc.first_child().empty());
+
+	CHECK_STRING(other.first_child().name(), STR("node1"));
+	CHECK(other.first_child().parent() == other);
+
+	CHECK_STRING(other.last_child().name(), STR("node2"));
+	CHECK(other.last_child().parent() == other);
+}
+
+TEST_XML(document_move_assign, "<node1/><node2/>")
+{
+	xml_document other;
+	CHECK(other.load_string(STR("<node3/>")));
+
+	other = std::move(doc);
+
+	CHECK(doc.first_child().empty());
+
+	CHECK_STRING(other.first_child().name(), STR("node1"));
+	CHECK(other.first_child().parent() == other);
+
+	CHECK_STRING(other.last_child().name(), STR("node2"));
+	CHECK(other.last_child().parent() == other);
+}
+
+TEST_XML(document_move_zero_alloc, "<node1/><node2/>")
+{
+	test_runner::_memory_fail_threshold = 1;
+
+	xml_document other = std::move(doc);
+
+	CHECK(doc.first_child().empty());
+
+	CHECK_STRING(other.first_child().name(), STR("node1"));
+	CHECK(other.first_child().parent() == other);
+
+	CHECK_STRING(other.last_child().name(), STR("node2"));
+	CHECK(other.last_child().parent() == other);
+}
+
+TEST(document_move_append_buffer)
+{
+	xml_document* doc = new xml_document();
+	CHECK(doc->load_string(STR("<node1 attr1='value1'><node2/></node1>")));
+	CHECK(doc->child(STR("node1")).append_buffer("<node3/>", 8));
+	CHECK(doc->child(STR("node1")).append_buffer("<node4/>", 8));
+
+	xml_document other = std::move(*doc);
+	delete doc;
+
+	CHECK(other.child(STR("node1")).append_buffer("<node5/>", 8));
+	CHECK(other.child(STR("node1")).append_buffer("<node6/>", 8));
+
+	CHECK_NODE(other, STR("<node1 attr1=\"value1\"><node2/><node3/><node4/><node5/><node6/></node1>"));
+}
+
+TEST(document_move_append_child)
+{
+	xml_document* doc = new xml_document();
+	CHECK(doc->load_string(STR("<node1 attr1='value1'><node2/></node1>")));
+
+	xml_document other = std::move(*doc);
+	delete doc;
+
+	for (int i = 0; i < 3000; ++i)
+		other.child(STR("node1")).append_child(STR("node"));
+
+	for (int i = 0; i < 3000; ++i)
+		other.child(STR("node1")).remove_child(other.child(STR("node1")).last_child());
+
+	CHECK_NODE(other, STR("<node1 attr1=\"value1\"><node2/></node1>"));
+
+	other.remove_child(other.first_child());
+
+	CHECK(!other.first_child());
+}
+
+TEST(document_move_empty)
+{
+	xml_document* doc = new xml_document();
+	xml_document other = std::move(*doc);
+	delete doc;
+}
+
+TEST(document_move_large)
+{
+	xml_document* doc = new xml_document();
+
+	xml_node dn = doc->append_child(STR("node"));
+
+	for (int i = 0; i < 3000; ++i)
+		dn.append_child(STR("child"));
+
+	xml_document other = std::move(*doc);
+	delete doc;
+
+	xml_node on = other.child(STR("node"));
+
+	for (int i = 0; i < 3000; ++i)
+		CHECK(on.remove_child(on.first_child()));
+
+	CHECK(!on.first_child());
+}
+
+TEST_XML(document_move_buffer, "<node1/><node2/>")
+{
+	CHECK(doc.child(STR("node2")).offset_debug() == 9);
+
+	xml_document other = std::move(doc);
+
+	CHECK(other.child(STR("node2")).offset_debug() == 9);
+}
+
+TEST_XML(document_move_append_child_zero_alloc, "<node1/><node2/>")
+{
+	test_runner::_memory_fail_threshold = 1;
+
+	xml_document other = std::move(doc);
+
+	CHECK(other.append_child(STR("node3")));
+
+	CHECK_NODE(other, STR("<node1/><node2/><node3/>"));
+}
+
+TEST(document_move_empty_zero_alloc)
+{
+	xml_document* docs = new xml_document[32];
+
+	test_runner::_memory_fail_threshold = 1;
+
+	for (int i = 1; i < 32; ++i)
+		docs[i] = std::move(docs[i-1]);
+
+	delete[] docs;
+}
+
+#ifndef PUGIXML_COMPACT
+TEST(document_move_repeated_zero_alloc)
+{
+	xml_document docs[32];
+
+	CHECK(docs[0].load_string(STR("<node><child/></node>")));
+
+	test_runner::_memory_fail_threshold = 1;
+
+	for (int i = 1; i < 32; ++i)
+		docs[i] = std::move(docs[i-1]);
+
+	for (int i = 0; i < 31; ++i)
+		CHECK(!docs[i].first_child());
+
+	CHECK_NODE(docs[31], STR("<node><child/></node>"));
+}
+#endif
+
+#ifdef PUGIXML_COMPACT
+TEST(document_move_compact_fail)
+{
+	xml_document docs[32];
+
+	CHECK(docs[0].load_string(STR("<node><child/></node>")));
+
+	test_runner::_memory_fail_threshold = 1;
+
+	int safe_count = 21;
+
+	for (int i = 1; i <= safe_count; ++i)
+		docs[i] = std::move(docs[i-1]);
+
+	CHECK_ALLOC_FAIL(docs[safe_count+1] = std::move(docs[safe_count]));
+
+	for (int i = 0; i < safe_count; ++i)
+		CHECK(!docs[i].first_child());
+
+	CHECK_NODE(docs[safe_count], STR("<node><child/></node>"));
+	CHECK(!docs[safe_count+1].first_child());
+}
+#endif
+#endif