[ClassMapGenerator] Refine the findClasses method

The code could not throw

src/Composer/Autoload/ClassMapGenerator.php

@@ -96,6 +96,10 @@ class ClassMapGenerator
 
         try {
             $contents = php_strip_whitespace($path);
+        } catch (\Exception $e) {
+            throw new \RuntimeException('Could not scan for classes inside '.$path.": \n".$e->getMessage(), 0, $e);
+        }
+
         if (!preg_match('{\b(?:class|interface'.$traits.')\b}i', $contents)) {
             return array();
         }
@@ -116,8 +120,6 @@ class ClassMapGenerator
         $namespace = '';
 
         for ($i = 0, $len = count($matches['type']); $i < $len; $i++) {
-                $name = $matches['name'][$i];
-
             if (!empty($matches['ns'][$i])) {
                 $namespace = str_replace(array(' ', "\t", "\r", "\n"), '', $matches['nsname'][$i]) . '\\';
             } else {
@@ -126,8 +128,6 @@ class ClassMapGenerator
         }
 
         return $classes;
-        } catch (\Exception $e) {
+
-            throw new \RuntimeException('Could not scan for classes inside '.$path.": \n".$e->getMessage(), 0, $e);
-        }
     }
 }

tests/Composer/Test/Autoload/ClassMapGeneratorTest.php

@@ -84,6 +84,19 @@ class ClassMapGeneratorTest extends \PHPUnit_Framework_TestCase
         ), ClassMapGenerator::createMap($finder));
     }
 
+    /**
+     * @expectedException \RuntimeException
+     * @expectedExceptionMessage Could not scan for classes inside
+     */
+    public function testThrowsWhenFileDoesNotExist()
+    {
+        $r = new \ReflectionClass('Composer\\Autoload\\ClassMapGenerator');
+        $find = $r->getMethod('findClasses');
+        $find->setAccessible(true);
+
+        $find->invoke(null, __DIR__.'/no-file');
+    }
+
     protected function assertEqualsNormalized($expected, $actual, $message = null)
     {
         foreach ($expected as $ns => $path) {