Add a test for cowboy:set_env

ebin/cowboy.app

@@ -1,6 +1,6 @@
 {application, 'cowboy', [
 	{description, "Small, fast, modern HTTP server."},
-	{vsn, "2.0.0-pre.7"},
+	{vsn, "2.0.0-pre.8"},
 	{modules, ['cowboy','cowboy_app','cowboy_bstr','cowboy_clear','cowboy_clock','cowboy_compress_h','cowboy_constraints','cowboy_handler','cowboy_http','cowboy_http2','cowboy_loop','cowboy_middleware','cowboy_req','cowboy_rest','cowboy_router','cowboy_static','cowboy_stream','cowboy_stream_h','cowboy_sub_protocol','cowboy_sup','cowboy_tls','cowboy_websocket']},
 	{registered, [cowboy_sup,cowboy_clock]},
 	{applications, [kernel,stdlib,crypto,cowlib,ranch]},

test/misc_SUITE.erl

@@ -0,0 +1,50 @@
+%% Copyright (c) 2017, Loïc Hoguin <essen@ninenines.eu>
+%%
+%% Permission to use, copy, modify, and/or distribute this software for any
+%% purpose with or without fee is hereby granted, provided that the above
+%% copyright notice and this permission notice appear in all copies.
+%%
+%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+-module(misc_SUITE).
+-compile(export_all).
+
+-import(ct_helper, [config/2]).
+-import(ct_helper, [doc/1]).
+-import(cowboy_test, [gun_open/1]).
+
+all() ->
+	cowboy_test:common_all().
+
+groups() ->
+	cowboy_test:common_groups(ct_helper:all(?MODULE)).
+
+init_per_group(Name, Config) ->
+	cowboy_test:init_common_groups(Name, Config, ?MODULE).
+
+end_per_group(Name, _) ->
+	cowboy:stop_listener(Name).
+
+init_dispatch(_) ->
+	cowboy_router:compile([{"localhost", [
+		{"/", hello_h, []}
+	]}]).
+
+set_env(Config) ->
+	doc("Live replace a middleware environment value."),
+	ConnPid1 = gun_open(Config),
+	Ref1 = gun:get(ConnPid1, "/"),
+	{response, _, 200, _} = gun:await(ConnPid1, Ref1),
+	Listener = proplists:get_value(name, config(tc_group_properties, Config)),
+	cowboy:set_env(Listener, dispatch, []),
+	%% Only new connections get the updated environment.
+	ConnPid2 = gun_open(Config),
+	Ref2 = gun:get(ConnPid2, "/"),
+	{response, _, 400, _} = gun:await(ConnPid2, Ref2),
+	ok.