Addresses #131. Added check to see if TTY is available.

src/Command/CheckCommand.php

@@ -2,6 +2,7 @@
 
 namespace DrupalCheck\Command;
 
+use DrupalCheck\Util\Tty;
 use DrupalFinder\DrupalFinder;
 use Nette\Neon\Neon;
 use PHPStan\ShouldNotHappenException;
@@ -211,7 +212,7 @@ protected function execute(InputInterface $input, OutputInterface $output): int
         $command = array_merge($command, $paths);
 
         $process = new Process($command);
-        $process->setTty(true);
+        $process->setTty(Tty::isTtySupported());
         $process->setTimeout(null);
         $process->run(static function ($type, $buffer) use ($output) {
             if (Process::ERR === $type) {

src/Util/Tty.php

@@ -0,0 +1,28 @@
+<?php declare(strict_types=1);
+
+namespace DrupalCheck\Util;
+
+use Symfony\Component\Process\Process;
+
+/**
+ * Wrapper for universal support of TTY-related functionality across versions of
+ * Symfony Process.
+ */
+class Tty
+{
+    /**
+     * In Symfony Process 4+, this is simply a wrapper for Process::isTtySupported().
+     * In lower versions, it mimics the same functionality.
+     */
+    public static function isTtySupported()
+    {
+        // Start off by checking STDIN with `posix_isatty`, as that appears to be more reliable
+        if (function_exists('posix_isatty')) {
+            return posix_isatty(STDIN);
+        }
+        if (method_exists('\Symfony\Component\Process\Process', 'isTtySupported')) {
+            return Process::isTtySupported();
+        }
+        return (bool) @proc_open('echo 1 >/dev/null', array(array('file', '/dev/tty', 'r'), array('file', '/dev/tty', 'w'), array('file', '/dev/tty', 'w')), $pipes);
+    }
+}