bug #20377 [Console] Fix infinite loop on missing input (chalasr)

This PR was merged into the 2.7 branch.

Discussion
----------

[Console] Fix infinite loop on missing input

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #20277
| License       | MIT
| Doc PR        | n/a

This fixes the infinite loop occurring when no input is provided for a question which has a validator and no max attempts (`null`), e.g. when using `SymfonyStyle::ask()` which automatically adds a validator.

Commits
-------

e64de1e [Console] Fix infinite loop on missing input

src/Symfony/Component/Console/Exception/RuntimeException.php

@@ -0,0 +1,19 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Console\Exception;
+
+/**
+ * @author Jérôme Tamarelle <jerome@tamarelle.net>
+ */
+class RuntimeException extends \RuntimeException
+{
+}

src/Symfony/Component/Console/Helper/QuestionHelper.php

@@ -17,6 +17,7 @@ use Symfony\Component\Console\Output\OutputInterface;
 use Symfony\Component\Console\Formatter\OutputFormatterStyle;
 use Symfony\Component\Console\Question\Question;
 use Symfony\Component\Console\Question\ChoiceQuestion;
+use Symfony\Component\Console\Exception\RuntimeException;
 
 /**
  * The QuestionHelper class provides helpers to interact with the user.
@@ -134,7 +135,7 @@ class QuestionHelper extends Helper
             if (false === $ret) {
                 $ret = fgets($inputStream, 4096);
                 if (false === $ret) {
-                    throw new \RuntimeException('Aborted');
+                    throw new RuntimeException('Aborted');
                 }
                 $ret = trim($ret);
             }
@@ -354,7 +355,7 @@ class QuestionHelper extends Helper
             shell_exec(sprintf('stty %s', $sttyMode));
 
             if (false === $value) {
-                throw new \RuntimeException('Aborted');
+                throw new RuntimeException('Aborted');
             }
 
             $value = trim($value);
@@ -372,7 +373,7 @@ class QuestionHelper extends Helper
             return $value;
         }
 
-        throw new \RuntimeException('Unable to hide the response.');
+        throw new RuntimeException('Unable to hide the response.');
     }
 
     /**
@@ -397,6 +398,8 @@ class QuestionHelper extends Helper
 
             try {
                 return call_user_func($question->getValidator(), $interviewer());
+            } catch (RuntimeException $e) {
+                throw $e;
             } catch (\Exception $error) {
             }
         }

src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php

@@ -402,6 +402,37 @@ class QuestionHelperTest extends \PHPUnit_Framework_TestCase
         $dialog->ask($this->createInputInterfaceMock(), $output, $question);
     }
 
+    /**
+     * @expectedException        \Symfony\Component\Console\Exception\RuntimeException
+     * @expectedExceptionMessage Aborted
+     */
+    public function testAskThrowsExceptionOnMissingInput()
+    {
+        $dialog = new QuestionHelper();
+        $dialog->setInputStream($this->getInputStream(''));
+
+        $dialog->ask($this->createInputInterfaceMock(), $this->createOutputInterface(), new Question('What\'s your name?'));
+    }
+
+    /**
+     * @expectedException        \Symfony\Component\Console\Exception\RuntimeException
+     * @expectedExceptionMessage Aborted
+     */
+    public function testAskThrowsExceptionOnMissingInputWithValidator()
+    {
+        $dialog = new QuestionHelper();
+        $dialog->setInputStream($this->getInputStream(''));
+
+        $question = new Question('What\'s your name?');
+        $question->setValidator(function () {
+            if (!$value) {
+                throw new \Exception('A value is required.');
+            }
+        });
+
+        $dialog->ask($this->createInputInterfaceMock(), $this->createOutputInterface(), $question);
+    }
+
     protected function getInputStream($input)
     {
         $stream = fopen('php://memory', 'r+', false);

src/Symfony/Component/Console/Tests/Helper/SymfonyQuestionHelperTest.php

@@ -101,6 +101,18 @@ class SymfonyQuestionHelperTest extends \PHPUnit_Framework_TestCase
         $this->assertOutputContains('Do you want a \?', $output);
     }
 
+    /**
+     * @expectedException        \Symfony\Component\Console\Exception\RuntimeException
+     * @expectedExceptionMessage Aborted
+     */
+    public function testAskThrowsExceptionOnMissingInput()
+    {
+        $dialog = new SymfonyQuestionHelper();
+
+        $dialog->setInputStream($this->getInputStream(''));
+        $dialog->ask($this->createInputInterfaceMock(), $this->createOutputInterface(), new Question('What\'s your name?'));
+    }
+
     protected function getInputStream($input)
     {
         $stream = fopen('php://memory', 'r+', false);