[Console] Use readline for user input when available

This allows to use arrow keys in the terminal instead of having weird characters
symfony · fabpot · Aug 1, 2015 · Jul 28, 2015 · Jul 28, 2015 · Aug 1, 2015
commit 8b63d6209d7426b79c79fb3a9e88436db634ae92
diff --git a/src/Symfony/Component/Console/CHANGELOG.md b/src/Symfony/Component/Console/CHANGELOG.md
@@ -1,6 +1,12 @@
 CHANGELOG
 =========
 
+2.8.0
+-----
+
+ * use readline for user input in the question helper when available to allow
+   the use of arrow keys
+
 2.6.0
 -----
 

diff --git a/src/Symfony/Component/Console/Helper/QuestionHelper.php b/src/Symfony/Component/Console/Helper/QuestionHelper.php
@@ -127,11 +127,7 @@ public function doAsk(OutputInterface $output, Question $question)
             }
 
             if (false === $ret) {
-                $ret = fgets($inputStream, 4096);
-                if (false === $ret) {
-                    throw new \RuntimeException('Aborted');
-                }
-                $ret = trim($ret);
+                $ret = $this->readFromInput($inputStream);
             }
         } else {
             $ret = trim($this->autocomplete($output, $question, $inputStream));
@@ -423,6 +419,30 @@ private function getShell()
         return self::$shell;
     }
 
+    /**
+     * Reads user input.
+     *
+     * @param resource $stream The input stream
+     *
+     * @return string User input
+     *
+     * @throws \RuntimeException
+     */
+    private function readFromInput($stream)
+    {
+        if (STDIN === $stream && function_exists('readline')) {
+            $ret = readline();
+        } else {
+            $ret = fgets($stream, 4096);
+
+            if (false === $ret) {
+                throw new \RuntimeException('Aborted');
+            }
+        }
+
+        return trim($ret);
+    }
+
     /**
      * Returns whether Stty is available or not.
      *