Explicitly forward warnings to any registered error handlers

Author: clue

src/StreamSelectLoop.php

@@ -287,15 +287,28 @@ private function streamSelect(array &$read, array &$write, $timeout)
                 }
             }
 
-            // suppress warnings that occur when `stream_select()` is interrupted by a signal
-            \set_error_handler(function ($errno, $errstr) {
+            /** @var ?callable $previous */
+            $previous = \set_error_handler(function ($errno, $errstr) use (&$previous) {
+                // suppress warnings that occur when `stream_select()` is interrupted by a signal
                 $eintr = \defined('SOCKET_EINTR') ? \SOCKET_EINTR : 4;
-                return ($errno === \E_WARNING && \strpos($errstr, '[' . $eintr .']: ') !== false);
-            });
+                if ($errno === \E_WARNING && \strpos($errstr, '[' . $eintr .']: ') !== false) {
+                    return;
+                }
 
-            $ret = \stream_select($read, $write, $except, $timeout === null ? null : 0, $timeout);
+                // forward any other error to registered error handler or print warning
+                return ($previous !== null) ? \call_user_func_array($previous, \func_get_args()) : false;
+            });
 
-            \restore_error_handler();
+            try {
+                $ret = \stream_select($read, $write, $except, $timeout === null ? null : 0, $timeout);
+                \restore_error_handler();
+            } catch (\Throwable $e) { // @codeCoverageIgnoreStart
+                \restore_error_handler();
+                throw $e;
+            } catch (\Exception $e) {
+                \restore_error_handler();
+                throw $e;
+            } // @codeCoverageIgnoreEnd
 
             if ($except) {
                 $write = \array_merge($write, $except);

tests/StreamSelectLoopTest.php

@@ -40,6 +40,77 @@ public function testStreamSelectTimeoutEmulation()
         $this->assertGreaterThan(0.04, $interval);
     }
 
+    public function testStreamSelectReportsWarningForStreamWithFilter()
+    {
+        $stream = tmpfile();
+        stream_filter_append($stream, 'string.rot13');
+
+        $this->loop->addReadStream($stream, $this->expectCallableNever());
+
+        $loop = $this->loop;
+        $this->loop->futureTick(function () use ($loop, $stream) {
+            $loop->futureTick(function () use ($loop, $stream) {
+                $loop->removeReadStream($stream);
+            });
+        });
+
+        $error = null;
+        $previous = set_error_handler(function ($_, $errstr) use (&$error) {
+            $error = $errstr;
+        });
+
+        try {
+            $this->loop->run();
+        } catch (\ValueError $e) {
+            // ignore ValueError for PHP 8+ due to empty stream array
+        }
+
+        restore_error_handler();
+
+        $this->assertNotNull($error);
+
+        $now = set_error_handler(function () { });
+        restore_error_handler();
+        $this->assertEquals($previous, $now);
+    }
+
+    public function testStreamSelectThrowsWhenCustomErrorHandlerThrowsForStreamWithFilter()
+    {
+        $stream = tmpfile();
+        stream_filter_append($stream, 'string.rot13');
+
+        $this->loop->addReadStream($stream, $this->expectCallableNever());
+
+        $loop = $this->loop;
+        $this->loop->futureTick(function () use ($loop, $stream) {
+            $loop->futureTick(function () use ($loop, $stream) {
+                $loop->removeReadStream($stream);
+            });
+        });
+
+        $previous = set_error_handler(function ($_, $errstr) {
+            throw new \RuntimeException($errstr);
+        });
+
+        $e = null;
+        try {
+            $this->loop->run();
+            restore_error_handler();
+            $this->fail();
+        } catch (\RuntimeException $e) {
+            restore_error_handler();
+        } catch (\ValueError $e) {
+            restore_error_handler(); // PHP 8+
+            $e = $e->getPrevious();
+        }
+
+        $this->assertInstanceOf('RuntimeException', $e);
+
+        $now = set_error_handler(function () { });
+        restore_error_handler();
+        $this->assertEquals($previous, $now);
+    }
+
     public function signalProvider()
     {
         return array(