Don't kill on __destruct if streams are still used (#59)

src/Internal/ProcHolder.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace Amp\Process\Internal;
+
+final class ProcHolder
+{
+    private ProcessRunner $runner;
+
+    private ProcessHandle $handle;
+
+    public function __construct(ProcessRunner $runner, ProcessHandle $handle)
+    {
+        $this->runner = $runner;
+        $this->handle = $handle;
+    }
+
+    public function __destruct()
+    {
+        $this->runner->destroy($this->handle);
+    }
+}

src/Process.php

@@ -8,6 +8,7 @@ use Amp\Process\Internal\Posix\PosixRunner as PosixProcessRunner;
 use Amp\Process\Internal\ProcessHandle;
 use Amp\Process\Internal\ProcessRunner;
 use Amp\Process\Internal\ProcessStatus;
+use Amp\Process\Internal\ProcHolder;
 use Amp\Process\Internal\Windows\WindowsRunner as WindowsProcessRunner;
 use JetBrains\PhpStorm\ArrayShape;
 use Revolt\EventLoop;
@@ -16,6 +17,8 @@ final class Process
 {
     private static \WeakMap $driverRunner;
 
+    private static \WeakMap $procHolder;
+
     /**
      * Starts a new process.
      *
@@ -63,6 +66,14 @@ final class Process
             $options
         );
 
+        $procHolder = new ProcHolder($runner, $handle);
+
+        /** @psalm-suppress RedundantPropertyInitializationCheck */
+        self::$procHolder ??= new \WeakMap();
+        self::$procHolder[$handle->stdin] = $procHolder;
+        self::$procHolder[$handle->stdout] = $procHolder;
+        self::$procHolder[$handle->stderr] = $procHolder;
+
         return new self($runner, $handle, $command, $workingDirectory, $envVars, $options);
     }
 
@@ -95,14 +106,6 @@ final class Process
         $this->options = $options;
     }
 
-    /**
-     * Stops the process if it is still running.
-     */
-    public function __destruct()
-    {
-        $this->runner->destroy($this->handle);
-    }
-
     public function __clone()
     {
         throw new \Error("Cloning " . self::class . " is not allowed.");

test/ProcessTest.php

@@ -235,6 +235,19 @@ class ProcessTest extends AsyncTestCase
         self::assertSame(0, $process->join());
     }
 
+    public function testReadOutputAfterExitWithLongOutputDestructedProcess(): void
+    {
+        $process = Process::start(["php", __DIR__ . "/bin/worker.php"]);
+
+        $count = 128 * 1024 + 1;
+        $process->getStdin()->write("exit " . $count);
+        $stdout = $process->getStdout();
+
+        unset($process);
+
+        self::assertSame(\str_repeat(".", $count), buffer($stdout));
+    }
+
     public function testKillPHPImmediately(): void
     {
         $socket = \stream_socket_server("tcp://127.0.0.1:10000");