bug symfony#19298 [ClassLoader] Fix declared classes being computed when not needed (nicolas-grekas)

This PR was merged into the 2.7 branch.

Discussion
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[ClassLoader] Fix declared classes being computed when not needed

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

Commits
-------

d513eae [ClassLoader] Fix declared classes being computed when not needed

Author: nicolas-grekas

src/Symfony/Component/ClassLoader/ClassCollectionLoader.php

@@ -43,12 +43,12 @@ public static function load($classes, $cacheDir, $name, $autoReload, $adaptive =
 
         self::$loaded[$name] = true;
 
-        $declared = array_merge(get_declared_classes(), get_declared_interfaces());
-        if (function_exists('get_declared_traits')) {
-            $declared = array_merge($declared, get_declared_traits());
-        }
-
         if ($adaptive) {
+            $declared = array_merge(get_declared_classes(), get_declared_interfaces());
+            if (function_exists('get_declared_traits')) {
+                $declared = array_merge($declared, get_declared_traits());
+            }
+
             // don't include already declared classes
             $classes = array_diff($classes, $declared);
 
@@ -87,11 +87,17 @@ public static function load($classes, $cacheDir, $name, $autoReload, $adaptive =
             }
         }
 
-        if (!$reload && is_file($cache)) {
+        if (!$reload && file_exists($cache)) {
             require_once $cache;
 
             return;
         }
+        if (!$adaptive) {
+            $declared = array_merge(get_declared_classes(), get_declared_interfaces());
+            if (function_exists('get_declared_traits')) {
+                $declared = array_merge($declared, get_declared_traits());
+            }
+        }
 
         $files = array();
         $content = '';