diff --git a/src/Symfony/Component/Console/Helper/QuestionHelper.php b/src/Symfony/Component/Console/Helper/QuestionHelper.php
index 7e6d9c70b1..4b215b764f 100644
--- a/src/Symfony/Component/Console/Helper/QuestionHelper.php
+++ b/src/Symfony/Component/Console/Helper/QuestionHelper.php
@@ -284,7 +284,7 @@ class QuestionHelper extends Helper
 
                 foreach ($autocomplete as $value) {
                     // If typed characters match the beginning chunk of value (e.g. [AcmeDe]moBundle)
-                    if (0 === strpos($value, $ret) && $i !== strlen($value)) {
+                    if (0 === strpos($value, $ret)) {
                         $matches[$numMatches++] = $value;
                     }
                 }
diff --git a/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php b/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php
index d9bdb606ac..9f837d0f9e 100644
--- a/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php
+++ b/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php
@@ -160,6 +160,30 @@ class QuestionHelperTest extends TestCase
         $this->assertEquals('AsseticBundle', $dialog->ask($this->createInputInterfaceMock(), $this->createOutputInterface(), $question));
     }
 
+    public function testAskWithAutocompleteWithExactMatch()
+    {
+        if (!$this->hasSttyAvailable()) {
+            $this->markTestSkipped('`stty` is required to test autocomplete functionality');
+        }
+
+        $inputStream = $this->getInputStream("b\n");
+
+        $possibleChoices = array(
+            'a' => 'berlin',
+            'b' => 'copenhagen',
+            'c' => 'amsterdam',
+        );
+
+        $dialog = new QuestionHelper();
+        $dialog->setInputStream($inputStream);
+        $dialog->setHelperSet(new HelperSet(array(new FormatterHelper())));
+
+        $question = new ChoiceQuestion('Please select a city', $possibleChoices);
+        $question->setMaxAttempts(1);
+
+        $this->assertSame('b', $dialog->ask($this->createInputInterfaceMock(), $this->createOutputInterface(), $question));
+    }
+
     public function testAutocompleteWithTrailingBackslash()
     {
         if (!$this->hasSttyAvailable()) {
diff --git a/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php b/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php
index 1a4f3074b6..e088caa897 100644
--- a/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php
+++ b/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php
@@ -90,6 +90,10 @@ class LazyLoadingMetadataFactory implements MetadataFactoryInterface
             return $this->loadedClasses[$class];
         }
 
+        if (!class_exists($class) && !interface_exists($class, false)) {
+            throw new NoSuchMetadataException(sprintf('The class or interface "%s" does not exist.', $class));
+        }
+
         if (null !== $this->cache && false !== ($metadata = $this->cache->read($class))) {
             // Include constraints from the parent class
             $this->mergeConstraints($metadata);
@@ -97,10 +101,6 @@ class LazyLoadingMetadataFactory implements MetadataFactoryInterface
             return $this->loadedClasses[$class] = $metadata;
         }
 
-        if (!class_exists($class) && !interface_exists($class)) {
-            throw new NoSuchMetadataException(sprintf('The class or interface "%s" does not exist.', $class));
-        }
-
         $metadata = new ClassMetadata($class);
 
         if (null !== $this->loader) {
diff --git a/src/Symfony/Component/Validator/Tests/Mapping/Factory/LazyLoadingMetadataFactoryTest.php b/src/Symfony/Component/Validator/Tests/Mapping/Factory/LazyLoadingMetadataFactoryTest.php
index b5d1a9dc84..de6852271e 100644
--- a/src/Symfony/Component/Validator/Tests/Mapping/Factory/LazyLoadingMetadataFactoryTest.php
+++ b/src/Symfony/Component/Validator/Tests/Mapping/Factory/LazyLoadingMetadataFactoryTest.php
@@ -149,6 +149,21 @@ class LazyLoadingMetadataFactoryTest extends TestCase
         $this->assertEquals($metadata, $factory->getMetadataFor(self::PARENT_CLASS));
     }
 
+    /**
+     * @expectedException \Symfony\Component\Validator\Exception\NoSuchMetadataException
+     */
+    public function testNonClassNameStringValues()
+    {
+        $testedValue = 'error@example.com';
+        $loader = $this->getMockBuilder('Symfony\Component\Validator\Mapping\Loader\LoaderInterface')->getMock();
+        $cache = $this->getMockBuilder('Symfony\Component\Validator\Mapping\Cache\CacheInterface')->getMock();
+        $factory = new LazyLoadingMetadataFactory($loader, $cache);
+        $cache
+            ->expects($this->never())
+            ->method('read');
+        $factory->getMetadataFor($testedValue);
+    }
+
     public function testMetadataCacheWithRuntimeConstraint()
     {
         $cache = $this->getMockBuilder('Symfony\Component\Validator\Mapping\Cache\CacheInterface')->getMock();