function new(new_stream, _M)
	local function test(xml, expect_success, ex)
		local stanzas = {};
		local session = { notopen = true };
		local callbacks = {
			stream_ns = "streamns";
			stream_tag = "stream";
			default_ns = "stanzans";
			streamopened = function (_session)
				assert_equal(session, _session);
				assert_equal(session.notopen, true);
				_session.notopen = nil;
				return true;
			end;
			handlestanza = function (_session, stanza)
				assert_equal(session, _session);
				assert_equal(_session.notopen, nil);
				table.insert(stanzas, stanza);
			end;
			streamclosed = function (_session)
				assert_equal(session, _session);
				assert_equal(_session.notopen, nil);
				_session.notopen = nil;
			end;
		}
		if type(ex) == "table" then
			for k, v in pairs(ex) do
				if k ~= "_size_limit" then
					callbacks[k] = v;
				end
			end
		end
		local stream = new_stream(session, callbacks, size_limit);
		local ok, err = pcall(function ()
			assert(stream:feed(xml));
		end);

		if ok and type(expect_success) == "function" then
			expect_success(stanzas);
		end
		assert_equal(not not ok, not not expect_success, "Expected "..(expect_success and ("success ("..tostring(err)..")") or "failure"));
	end

	local function test_stanza(stanza, expect_success, ex)
		return test([[<stream:stream xmlns:stream="streamns" xmlns="stanzans">]]..stanza, expect_success, ex);
	end

	test([[<stream:stream xmlns:stream="streamns"/>]], true);
	test([[<stream xmlns="streamns"/>]], true);

	test([[<stream1 xmlns="streamns"/>]], false);
	test([[<stream xmlns="streamns1"/>]], false);
	test("<>", false);

	test_stanza("<message/>", function (stanzas)
		assert_equal(#stanzas, 1);
		assert_equal(stanzas[1].name, "message");
	end);
	test_stanza("< message>>>>/>\n", false);

	test_stanza([[<x xmlns:a="b">
		<y xmlns:a="c">
			<a:z/>
		</y>
		<a:z/>
	</x>]], function (stanzas)
		assert_equal(#stanzas, 1);
		local s = stanzas[1];
		assert_equal(s.name, "x");
		assert_equal(#s.tags, 2);

		assert_equal(s.tags[1].name, "y");
		assert_equal(s.tags[1].attr.xmlns, nil);

		assert_equal(s.tags[1].tags[1].name, "z");
		assert_equal(s.tags[1].tags[1].attr.xmlns, "c");

		assert_equal(s.tags[2].name, "z");
		assert_equal(s.tags[2].attr.xmlns, "b");

		assert_equal(s.namespaces, nil);
	end);
end