bug #22255 [Translation] avoid creating cache files for fallback loca…

…les. (aitboudad)

This PR was merged into the 2.7 branch.

Discussion
----------

[Translation] avoid creating cache files for fallback locales.

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #21163
| License       | MIT
| Doc PR        | ~

Commits
-------

22425b2 [Translation] avoid creating cache files for fallback locales.

src/Symfony/Component/Translation/Tests/TranslatorCacheTest.php

@@ -149,6 +149,17 @@ public function testDifferentTranslatorsForSameLocaleDoNotOverwriteEachOthersCac
         $this->assertEquals('OK', $translator->trans($msgid), '-> the cache was overwritten by another translator instance in '.($debug ? 'debug' : 'production'));
     }
 
+    public function testGeneratedCacheFilesAreOnlyBelongRequestedLocales()
+    {
+        $translator = new Translator('a', null, $this->tmpDir);
+        $translator->setFallbackLocales(array('b'));
+        $translator->trans('bar');
+
+        $cachedFiles = glob($this->tmpDir.'/*.php');
+
+        $this->assertCount(1, $cachedFiles);
+    }
+
     public function testDifferentCacheFilesAreUsedForDifferentSetsOfFallbackLocales()
     {
         /*

src/Symfony/Component/Translation/Translator.php

@@ -420,7 +420,7 @@ private function loadFallbackCatalogues($locale)
 
         foreach ($this->computeFallbackLocales($locale) as $fallback) {
             if (!isset($this->catalogues[$fallback])) {
-                $this->loadCatalogue($fallback);
+                $this->initializeCatalogue($fallback);
             }
 
             $fallbackCatalogue = new MessageCatalogue($fallback, $this->catalogues[$fallback]->all());