Fix IsFin mismatch in HTTP/2 CONNECT response

The response ends when the tunnel is established, even if the
stream itself does not. The data coming in on the stream after
is not part of the response.

This makes both HTTP/1.1 and HTTP/2 send 'fin' to successful
CONNECT responses.

6 files changed, 34 insertions, 62 deletions

diff --git a/test/event_SUITE.erl b/test/event_SUITE.erl
index 8be10b1..ca7c55d 100644
--- a/test/event_SUITE.erl
+++ b/test/event_SUITE.erl
@@ -530,8 +530,7 @@ do_request_event_connect(Config, EventName) ->
 	%% Gun doesn't send headers with an HTTP/2 CONNECT request
 	%% so we only check that the headers are given as a list.
 	true = is_list(Headers1),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/", [], #{tunnel => StreamRef1}),
 	#{
@@ -575,8 +574,7 @@ do_request_event_headers_connect(Config, EventName) ->
 	%% Gun doesn't send headers with an HTTP/2 CONNECT request
 	%% so we only check that the headers are given as a list.
 	true = is_list(Headers1),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:put(ConnPid, "/", [
 		{<<"content-type">>, <<"text/plain">>}
@@ -685,8 +683,7 @@ do_request_end_connect(Config, EventName) ->
 		stream_ref := StreamRef1,
 		reply_to := ReplyTo
 	} = do_receive_event(EventName),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/", [], #{tunnel => StreamRef1}),
 	#{
@@ -715,8 +712,7 @@ do_request_end_headers_connect(Config, EventName) ->
 		stream_ref := StreamRef1,
 		reply_to := ReplyTo
 	} = do_receive_event(EventName),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:put(ConnPid, "/", [
 		{<<"content-type">>, <<"text/plain">>}
@@ -749,8 +745,7 @@ do_request_end_headers_content_length_connect(Config, EventName) ->
 		stream_ref := StreamRef1,
 		reply_to := ReplyTo
 	} = do_receive_event(EventName),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:put(ConnPid, "/", [
 		{<<"content-type">>, <<"text/plain">>},
@@ -784,8 +779,7 @@ do_request_end_headers_content_length_0_connect(Config, EventName) ->
 		stream_ref := StreamRef1,
 		reply_to := ReplyTo
 	} = do_receive_event(EventName),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:put(ConnPid, "/", [
 		{<<"content-type">>, <<"text/plain">>},
@@ -836,8 +830,7 @@ do_push_promise_start_connect(Config, ProxyProtocol) ->
 		port => OriginPort,
 		protocols => [http2]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, http2} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/push", [], #{tunnel => StreamRef1}),
 	ReplyTo = self(),
@@ -895,8 +888,7 @@ do_push_promise_end_connect(Config, ProxyProtocol) ->
 		port => OriginPort,
 		protocols => [http2]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, http2} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/push", [], #{tunnel => StreamRef1}),
 	ReplyTo = self(),
@@ -966,8 +958,7 @@ response_start_connect(Config) ->
 		stream_ref := StreamRef1,
 		reply_to := ReplyTo
 	} = do_receive_event(response_start),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/", [], #{tunnel => StreamRef1}),
 	#{
@@ -1014,8 +1005,7 @@ response_inform_connect(Config) ->
 		port => OriginPort,
 		protocols => [Protocol]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/inform", [], #{tunnel => StreamRef1}),
 	#{
@@ -1071,8 +1061,7 @@ response_headers_connect(Config) ->
 		headers := Headers1
 	} = do_receive_event(response_headers),
 	true = is_list(Headers1),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/", [], #{tunnel => StreamRef1}),
 	#{
@@ -1101,8 +1090,7 @@ response_trailers(Config) ->
 		port => OriginPort,
 		protocols => [Protocol]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/trailers", [{<<"te">>, <<"trailers">>}], #{tunnel => StreamRef1}),
 	#{
@@ -1159,8 +1147,7 @@ do_response_end_connect(Config, EventName, Path) ->
 %		stream_ref := StreamRef1,
 %		reply_to := ReplyTo
 %	} = do_receive_event(EventName),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, Path, [{<<"te">>, <<"trailers">>}], #{tunnel => StreamRef1}),
 	#{
@@ -1213,8 +1200,7 @@ http1_response_end_body_close(Config) ->
 %%		stream_ref := StreamRef1,
 %%		reply_to := ReplyTo
 %%	} = do_receive_event(EventName),
-%	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-%	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+%	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 %	{up, http} = gun:await(ConnPid, StreamRef1),
 %	StreamRef2 = gun:get(ConnPid, "/stream", [], #{tunnel => StreamRef1}),
 %	#{
@@ -1265,8 +1251,7 @@ do_ws_upgrade_connect(Config, ProxyProtocol) ->
 			http2 -> {http2, #{notify_settings_changed => true}}
 		end]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef1),
 	ws_SUITE:do_await_enable_connect_protocol(OriginProtocol, ConnPid),
 	StreamRef2 = gun:ws_upgrade(ConnPid, "/ws", [], #{tunnel => StreamRef1}),
@@ -1374,8 +1359,7 @@ do_ws_upgrade_all_events_connect(Config, ProxyProtocol) ->
 			http2 -> {http2, #{notify_settings_changed => true}}
 		end]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef1),
 	ws_SUITE:do_await_enable_connect_protocol(OriginProtocol, ConnPid),
 	%% Skip all CONNECT-related events that may conflict.
@@ -1502,8 +1486,7 @@ do_ws_recv_frame_start_connect(Config, ProxyProtocol) ->
 			http2 -> {http2, #{notify_settings_changed => true}}
 		end]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef1),
 	ws_SUITE:do_await_enable_connect_protocol(OriginProtocol, ConnPid),
 	StreamRef2 = gun:ws_upgrade(ConnPid, "/ws", [], #{tunnel => StreamRef1}),
@@ -1564,8 +1547,7 @@ do_ws_recv_frame_header_connect(Config, ProxyProtocol) ->
 			http2 -> {http2, #{notify_settings_changed => true}}
 		end]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef1),
 	ws_SUITE:do_await_enable_connect_protocol(OriginProtocol, ConnPid),
 	StreamRef2 = gun:ws_upgrade(ConnPid, "/ws", [], #{tunnel => StreamRef1}),
@@ -1627,8 +1609,7 @@ do_ws_recv_frame_end_connect(Config, ProxyProtocol) ->
 			http2 -> {http2, #{notify_settings_changed => true}}
 		end]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef1),
 	ws_SUITE:do_await_enable_connect_protocol(OriginProtocol, ConnPid),
 	StreamRef2 = gun:ws_upgrade(ConnPid, "/ws", [], #{tunnel => StreamRef1}),
@@ -1701,8 +1682,7 @@ do_ws_send_frame_connect(Config, ProxyProtocol, EventName) ->
 			http2 -> {http2, #{notify_settings_changed => true}}
 		end]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef1),
 	ws_SUITE:do_await_enable_connect_protocol(OriginProtocol, ConnPid),
 	StreamRef2 = gun:ws_upgrade(ConnPid, "/ws", [], #{tunnel => StreamRef1}),
@@ -1754,8 +1734,7 @@ do_ws_protocol_changed_connect(Config, ProxyProtocol) ->
 			http2 -> {http2, #{notify_settings_changed => true}}
 		end]
 	}, []),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef1),
 	ws_SUITE:do_await_enable_connect_protocol(OriginProtocol, ConnPid),
 	#{
@@ -1955,8 +1934,7 @@ cancel_connect(Config) ->
 		port => OriginPort,
 		protocols => [Protocol]
 	}),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:post(ConnPid, "/stream", [], #{tunnel => StreamRef1}),
 	gun:cancel(ConnPid, StreamRef2),
@@ -1987,8 +1965,7 @@ cancel_remote_connect(Config) ->
 		port => OriginPort,
 		protocols => [Protocol]
 	}),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:post(ConnPid, "/stream", [], #{tunnel => StreamRef1}),
 	ReplyTo = self(),
diff --git a/test/raw_SUITE.erl b/test/raw_SUITE.erl
index d909dce..a3b06c7 100644
--- a/test/raw_SUITE.erl
+++ b/test/raw_SUITE.erl
@@ -139,7 +139,7 @@ do_connect_raw(OriginTransport, ProxyTransport) ->
 		protocols => [raw]
 	}),
 	{request, <<"CONNECT">>, Authority, 'HTTP/1.1', _} = receive_from(ProxyPid),
-	{response, fin, 200, _} = gun:await(ConnPid, StreamRef), %% @todo Why fin?
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef),
 	handshake_completed = receive_from(OriginPid),
 	{up, raw} = gun:await(ConnPid, StreamRef),
 	gun:data(ConnPid, StreamRef, nofin, <<"Hello world!">>),
@@ -294,7 +294,7 @@ do_http2_connect_raw(OriginTransport, ProxyScheme, ProxyTransport) ->
 		<<":method">> := <<"CONNECT">>,
 		<<":authority">> := Authority
 	}} = receive_from(ProxyPid),
-	{response, nofin, 200, _} = gun:await(ConnPid, StreamRef),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef),
 	handshake_completed = receive_from(OriginPid),
 	{up, raw} = gun:await(ConnPid, StreamRef),
 	gun:data(ConnPid, StreamRef, nofin, <<"Hello world!">>),
diff --git a/test/rfc6265bis_SUITE.erl b/test/rfc6265bis_SUITE.erl
index b4b443d..4301fc3 100644
--- a/test/rfc6265bis_SUITE.erl
+++ b/test/rfc6265bis_SUITE.erl
@@ -193,8 +193,7 @@ set_cookie_connect_tcp(Config) ->
 		transport => Transport,
 		protocols => [Protocol]
 	}),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/cookie-set?prefix", #{
 		<<"please-set-cookie">> => <<"a=b">>
@@ -226,8 +225,7 @@ set_cookie_connect_tls(Config) ->
 		transport => Transport,
 		protocols => [Protocol]
 	}),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	StreamRef2 = gun:get(ConnPid, "/cookie-set?prefix", #{
 		<<"please-set-cookie">> => <<"a=b">>
diff --git a/test/rfc7540_SUITE.erl b/test/rfc7540_SUITE.erl
index 8680031..161c59f 100644
--- a/test/rfc7540_SUITE.erl
+++ b/test/rfc7540_SUITE.erl
@@ -521,7 +521,7 @@ do_connect_http(OriginScheme, OriginTransport, OriginProtocol, ProxyScheme, Prox
 		<<":method">> := <<"CONNECT">>,
 		<<":authority">> := Authority
 	}} = receive_from(ProxyPid),
-	{response, nofin, 200, _} = gun:await(ConnPid, StreamRef),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef),
 	handshake_completed = receive_from(OriginPid),
 	{up, OriginProtocol} = gun:await(ConnPid, StreamRef),
 	ProxiedStreamRef = gun:get(ConnPid, "/proxied", #{}, #{tunnel => StreamRef}),
@@ -624,7 +624,7 @@ do_connect_cowboy(_OriginScheme, OriginTransport, OriginProtocol, _ProxyScheme,
 			<<":method">> := <<"CONNECT">>,
 			<<":authority">> := Authority
 		}} = receive_from(ProxyPid),
-		{response, nofin, 200, _} = gun:await(ConnPid, StreamRef),
+		{response, fin, 200, _} = gun:await(ConnPid, StreamRef),
 		{up, OriginProtocol} = gun:await(ConnPid, StreamRef),
 		ProxiedStreamRef = gun:get(ConnPid, "/proxied", #{}, #{tunnel => StreamRef}),
 		timer:sleep(1000), %% @todo Why?
@@ -673,7 +673,7 @@ connect_handshake_timeout(_) ->
 		port => OriginPort,
 		protocols => [{http2, #{preface_timeout => 500}}]
 	}),
-	{response, nofin, 200, _} = gun:await(ConnPid, StreamRef),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef),
 	{up, http2} = gun:await(ConnPid, StreamRef),
 	%% @todo The error should be normalized.
 	%% @todo Do we want to indicate that a connection_error occurred within the tunnel stream?
@@ -721,7 +721,7 @@ do_connect_via_multiple_proxies(OriginTransport, OriginProtocol,
 			<<":method">> := <<"CONNECT">>,
 			<<":authority">> := Authority1
 		}} = receive_from(Proxy1Pid),
-		{response, nofin, 200, _} = gun:await(ConnPid, StreamRef1),
+		{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 		{up, Proxy2Protocol} = gun:await(ConnPid, StreamRef1),
 		%% Origin.
 		StreamRef2 = gun:connect(ConnPid, #{
@@ -732,7 +732,6 @@ do_connect_via_multiple_proxies(OriginTransport, OriginProtocol,
 		}, [], #{tunnel => StreamRef1}),
 		Authority2 = iolist_to_binary(["localhost:", integer_to_binary(OriginPort)]),
 		{request, <<"CONNECT">>, Authority2, 'HTTP/1.1', _} = receive_from(Proxy2Pid),
-		%% @todo OK there's a mismatch between HTTP/1.1 (fin) and HTTP/2 (nofin).
 		{response, fin, 200, _} = gun:await(ConnPid, StreamRef2),
 		{up, OriginProtocol} = gun:await(ConnPid, StreamRef2),
 		%% Tunneled request to the origin.
diff --git a/test/socks_SUITE.erl b/test/socks_SUITE.erl
index f6686a3..e23124f 100644
--- a/test/socks_SUITE.erl
+++ b/test/socks_SUITE.erl
@@ -449,7 +449,7 @@ do_socks5_through_h2_connect_proxy(_OriginScheme, OriginTransport, ProxyScheme,
 		<<":method">> := <<"CONNECT">>,
 		<<":authority">> := Authority1
 	}} = receive_from(Proxy1Pid),
-	{response, nofin, 200, _} = gun:await(ConnPid, StreamRef),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef),
 	%% First the HTTP/2 tunnel is up, then the SOCKS tunnel to the origin HTTP server.
 	{up, socks} = gun:await(ConnPid, StreamRef),
 	{up, http} = gun:await(ConnPid, StreamRef),
diff --git a/test/tunnel_SUITE.erl b/test/tunnel_SUITE.erl
index 6cc50f8..e5fad34 100644
--- a/test/tunnel_SUITE.erl
+++ b/test/tunnel_SUITE.erl
@@ -886,8 +886,7 @@ do_proxy2(State=#st{proxy2=Type, proxy2_pid=Proxy2Pid, proxy2_port=Port}, ConnPi
 				Protocol
 		end]
 	}),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef1),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef1),
 	{up, Protocol} = gun:await(ConnPid, StreamRef1),
 	do_handshake_completed(Protocol, Proxy2Pid),
 	StreamRef1.
@@ -908,8 +907,7 @@ do_origin(#st{origin=Type, origin_port=Port}, ConnPid, StreamRef1) ->
 		transport => Transport,
 		protocols => [Protocol]
 	}, [], #{tunnel => StreamRef1}),
-	%% @todo _IsFin is 'fin' for HTTP and 'nofin' for HTTP/2...
-	{response, _IsFin, 200, _} = gun:await(ConnPid, StreamRef2),
+	{response, fin, 200, _} = gun:await(ConnPid, StreamRef2),
 	{up, Protocol} = gun:await(ConnPid, StreamRef2),
 	StreamRef2.