Update test suite to ensure 100% code coverage

.github/workflows/ci.yml

@@ -33,7 +33,14 @@ jobs:
           php-version: ${{ matrix.php }}
           coverage: xdebug
       - run: composer install
-      - run: vendor/bin/phpunit --coverage-text ${{ matrix.php < 7.3 && '-c phpunit.xml.legacy' || '' }}
+      - run: vendor/bin/phpunit --coverage-text --coverage-clover clover.xml ${{ matrix.php < 7.3 && '-c phpunit.xml.legacy' || '' }}
+      - name: Check 100% code coverage
+        if: ${{ matrix.php >= 5.4 }}
+        shell: php {0}
+        run: |
+          <?php
+          $metrics = simplexml_load_file('clover.xml')->project->metrics;
+          exit((int) $metrics['statements'] === (int) $metrics['coveredstatements'] ? 0 : 1);
 
   PHPUnit-hhvm:
     name: PHPUnit (HHVM)

README.md

@@ -1,6 +1,7 @@
 # clue/reactphp-multicast
 
 [![CI status](https://github.com/clue/reactphp-multicast/actions/workflows/ci.yml/badge.svg)](https://github.com/clue/reactphp-multicast/actions)
+[![code coverage](https://img.shields.io/badge/code%20coverage-100%25-success)](#tests)
 [![installs on Packagist](https://img.shields.io/packagist/dt/clue/multicast-react?color=blue&label=installs%20on%20Packagist)](https://packagist.org/packages/clue/multicast-react)
 
 Simple, event-driven multicast UDP message client and server for [ReactPHP](https://reactphp.org/).
@@ -186,6 +187,15 @@ To run the test suite, go to the project root and run:
 vendor/bin/phpunit
 ```
 
+The test suite is set up to always ensure 100% code coverage across all
+supported environments (except `createReceiver()` on legacy PHP 5.3). If you
+have the Xdebug extension installed, you can also generate a code coverage
+report locally like this:
+
+```bash
+XDEBUG_MODE=coverage vendor/bin/phpunit --coverage-text
+```
+
 ## License
 
 This project is released under the permissive [MIT license](LICENSE).

src/Factory.php

@@ -58,6 +58,8 @@ public function __construct($loop = null)
     public function createSender()
     {
         $stream = @stream_socket_server('udp://0.0.0.0:0', $errno, $errstr, STREAM_SERVER_BIND);
+
+        // unlikely: stream_socket_server() may return false if no more file descriptors are available
         if ($stream === false) {
             throw new RuntimeException('Unable to create sending socket: ' . $errstr, $errno);
         }
@@ -104,10 +106,10 @@ public function createSender()
     public function createReceiver($address)
     {
         if (!defined('MCAST_JOIN_GROUP')) {
-            throw new BadMethodCallException('MCAST_JOIN_GROUP not defined (requires PHP 5.4+)');
+            throw new BadMethodCallException('MCAST_JOIN_GROUP not defined (requires PHP 5.4+)'); // @codeCoverageIgnore
         }
         if (!function_exists('socket_import_stream')) {
-            throw new BadMethodCallException('Function socket_import_stream missing (requires ext-sockets and PHP 5.4+)');
+            throw new BadMethodCallException('Function socket_import_stream missing (requires ext-sockets and PHP 5.4+)'); // @codeCoverageIgnore
         }
 
         $parts = parse_url('udp://' . $address);
@@ -118,15 +120,7 @@ public function createReceiver($address)
         }
 
         $socket = socket_import_stream($stream);
-        if ($stream === false) {
-            throw new RuntimeException('Unable to access underlying socket resource');
-        }
-
-        // allow multiple processes to bind to the same address
-        $ret = socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);
-        if ($ret === false) {
-            throw new RuntimeException('Unable to enable SO_REUSEADDR');
-        }
+        assert($socket !== false);
 
         set_error_handler(function () {
             // ignore PHP warning, error is reported via socket_last_error() below

tests/FunctionalTest.php

@@ -58,12 +58,70 @@ public function testMultipleReceivers()
         $this->loop->run();
     }
 
+    public function testCreateSenderThrowsWhenFileDescriptorsAreExceeded()
+    {
+        $ulimit = exec('ulimit -n 2>&1', $_, $exit);
+        if ($exit !== 0 || $ulimit < 1) {
+            $this->markTestSkipped('Unable to determine limit of open files (ulimit not available?)');
+        }
+
+        $memory = ini_get('memory_limit');
+        if ($memory === '-1') {
+            $memory = PHP_INT_MAX;
+        } elseif (preg_match('/^\d+G$/i', $memory)) {
+            $memory = ((int) $memory) * 1024 * 1024 * 1024;
+        } elseif (preg_match('/^\d+M$/i', $memory)) {
+            $memory = ((int) $memory) * 1024 * 1024;
+        } elseif (preg_match('/^\d+K$/i', $memory)) {
+            $memory = ((int) $memory) * 1024;
+        }
+
+        // each file descriptor takes ~600 bytes of memory, so skip test if this would exceed memory_limit
+        if ($ulimit * 600 > $memory || $ulimit > 100000) {
+            $this->markTestSkipped('Test requires ~' . round($ulimit * 600 / 1024 / 1024) . '/' . round($memory / 1024 / 1024) . ' MiB memory with ' . $ulimit . ' file descriptors');
+        }
+
+        // keep creating dummy file handles until all file descriptors are exhausted
+        $fds = array();
+        for ($i = 0; $i < $ulimit; ++$i) {
+            $fd = @fopen('/dev/null', 'r');
+            if ($fd === false) {
+                break;
+            }
+            $fds[] = $fd;
+        }
+
+        $this->setExpectedException('RuntimeException', 'Unable to create sending socket: ');
+        $this->factory->createSender();
+    }
+
+    public function testCreateReceiverThrowsForPortAlreadyInUse()
+    {
+        if (!defined('MCAST_JOIN_GROUP') || !function_exists('socket_import_stream')) {
+            $this->markTestSkipped('No multicast support');
+        }
+
+        // bind to random port without SO_REUSEADDR, so receiver can not bind to same port
+        $socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
+        socket_bind($socket, '0.0.0.0', 0);
+        socket_getsockname($socket, $host, $port);
+
+        $this->setExpectedException('RuntimeException', 'Unable to create receiving socket: ' . socket_strerror(SOCKET_EADDRINUSE));
+        $this->factory->createReceiver('224.224.244.244:' . $port);
+    }
+
     public function testCreateReceiverThrowsForNonMulticastAddressWithoutCallingCustomErrorHandler()
     {
         if (!defined('MCAST_JOIN_GROUP') || !function_exists('socket_import_stream')) {
             $this->markTestSkipped('No multicast support');
         }
 
+        // find random free port, as createReceiver() can not parse port 0 on legacy PHP
+        $socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
+        socket_bind($socket, '0.0.0.0', 0);
+        socket_getsockname($socket, $host, $port);
+        socket_close($socket);
+
         $error = null;
         set_error_handler(function ($_, $errstr) use (&$error) {
             $error = $errstr;
@@ -72,7 +130,7 @@ public function testCreateReceiverThrowsForNonMulticastAddressWithoutCallingCust
         $this->setExpectedException('RuntimeException', 'Unable to join multicast group: ' . socket_strerror(SOCKET_EINVAL), SOCKET_EINVAL);
 
         try {
-            $this->factory->createReceiver('127.0.0.1:2244');
+            $this->factory->createReceiver('127.0.0.1:' . $port);
 
             restore_error_handler();
         } catch (\Exception $e) {