Work around failing test case detecting EOF on TLS 1.3 socket streams

This PR improves the test suite to avoid a possible race condition for
our TLS tests. It does not change anything about the actual behavior or
the expected output, but it helps making the expected output more
explicit and no longer subject to a possible race condition. This helps
avoiding possible false negatives if TLS 1.3 is supported and PHP
reports the EOF indicator before consuming all application data.

This builds on top of reactphp#185 and
reactphp#186

tests/FunctionalSecureServerTest.php

@@ -718,21 +718,4 @@ private function createPromiseForEvent(EventEmitterInterface $emitter, $event, $
             });
         });
     }
-
-    private function supportsTls13()
-    {
-        // TLS 1.3 is supported as of OpenSSL 1.1.1 (https://www.openssl.org/blog/blog/2018/09/11/release111/)
-        // The OpenSSL library version can only be obtained by parsing output from phpinfo().
-        // OPENSSL_VERSION_TEXT refers to header version which does not necessarily match actual library version
-        // see php -i | grep OpenSSL
-        // OpenSSL Library Version => OpenSSL 1.1.1  11 Sep 2018
-        ob_start();
-        phpinfo(INFO_MODULES);
-        $info = ob_get_clean();
-
-        if (preg_match('/OpenSSL Library Version => OpenSSL (\S+)/', $info, $match)) {
-            return version_compare($match[1], '1.1.1', '>=');
-        }
-        return false;
-    }
 }

tests/SecureIntegrationTest.php

@@ -93,6 +93,21 @@ public function testSendSmallDataToServerReceivesOneChunk()
 
     public function testSendDataWithEndToServerReceivesAllData()
     {
+        // PHP can report EOF on TLS 1.3 stream before consuming all data, so
+        // we explicitly use older TLS version instead. Selecting TLS version
+        // requires PHP 5.6+, so skip legacy versions if TLS 1.3 is supported.
+        // Continue if TLS 1.3 is not supported anyway.
+        if ($this->supportsTls13()) {
+            if (!defined('STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT')) {
+                $this->markTestSkipped('TLS 1.3 supported, but this legacy PHP version does not support explicit choice');
+            }
+
+            $this->connector = new SecureConnector(new TcpConnector($this->loop), $this->loop, array(
+                'verify_peer' => false,
+                'crypto_method' => STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT
+            ));
+        }
+
         $disconnected = new Deferred();
         $this->server->on('connection', function (ConnectionInterface $peer) use ($disconnected) {
             $received = '';
@@ -113,6 +128,7 @@ public function testSendDataWithEndToServerReceivesAllData()
         // await server to report connection "close" event
         $received = Block\await($disconnected->promise(), $this->loop, self::TIMEOUT);
 
+        $this->assertEquals(strlen($data), strlen($received));
         $this->assertEquals($data, $received);
     }
 
@@ -136,6 +152,7 @@ public function testSendDataWithoutEndingToServerReceivesAllData()
 
         $client->close();
 
+        $this->assertEquals(strlen($data), strlen($received));
         $this->assertEquals($data, $received);
     }
 

tests/TestCase.php

@@ -98,4 +98,21 @@ public function setExpectedException($exception, $exceptionMessage = '', $except
             parent::setExpectedException($exception, $exceptionMessage, $exceptionCode);
         }
     }
+
+    protected function supportsTls13()
+    {
+        // TLS 1.3 is supported as of OpenSSL 1.1.1 (https://www.openssl.org/blog/blog/2018/09/11/release111/)
+        // The OpenSSL library version can only be obtained by parsing output from phpinfo().
+        // OPENSSL_VERSION_TEXT refers to header version which does not necessarily match actual library version
+        // see php -i | grep OpenSSL
+        // OpenSSL Library Version => OpenSSL 1.1.1  11 Sep 2018
+        ob_start();
+        phpinfo(INFO_MODULES);
+        $info = ob_get_clean();
+
+        if (preg_match('/OpenSSL Library Version => OpenSSL ([\d\.]+)/', $info, $match)) {
+            return version_compare($match[1], '1.1.1', '>=');
+        }
+        return false;
+    }
 }