Fix output when loading zips from cache, fixes #7498

src/Composer/Downloader/FileDownloader.php

@@ -137,8 +137,11 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
             $checksum = $package->getDistSha1Checksum();
             $cacheKey = $this->getCacheKey($package, $processedUrl);
 
-            // download if we don't have it in cache or the cache is invalidated
-            if (!$this->cache || ($checksum && $checksum !== $this->cache->sha1($cacheKey)) || !$this->cache->copyTo($cacheKey, $fileName)) {
+            // use from cache if it is present and has a valid checksum or we have no checksum to check against
+            if ($this->cache && (!$checksum || $checksum === $this->cache->sha1($cacheKey)) && $this->cache->copyTo($cacheKey, $fileName)) {
+                $this->io->writeError('Loading from cache', false);
+            } else {
+                // download if cache restore failed
                 if (!$this->outputProgress) {
                     $this->io->writeError('Downloading', false);
                 }
@@ -168,10 +171,6 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
                     $this->lastCacheWrites[$package->getName()] = $cacheKey;
                     $this->cache->copyFrom($cacheKey, $fileName);
                 }
-            } else {
-                if (!$this->outputProgress) {
-                    $this->io->writeError('Loading from cache', false);
-                }
             }
 
             if (!file_exists($fileName)) {
@@ -297,19 +296,27 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
         $this->io = new NullIO;
         $this->io->loadConfiguration($this->config);
         $this->outputProgress = false;
+        $e = null;
 
-        $this->download($package, $targetDir.'_compare', false);
-
-        $comparer = new Comparer();
-        $comparer->setSource($targetDir.'_compare');
-        $comparer->setUpdate($targetDir);
-        $comparer->doCompare();
-        $output = $comparer->getChanged(true, true);
-        $this->filesystem->removeDirectory($targetDir.'_compare');
+        try {
+            $this->download($package, $targetDir.'_compare', false);
+
+            $comparer = new Comparer();
+            $comparer->setSource($targetDir.'_compare');
+            $comparer->setUpdate($targetDir);
+            $comparer->doCompare();
+            $output = $comparer->getChanged(true, true);
+            $this->filesystem->removeDirectory($targetDir.'_compare');
+        } catch (\Exception $e) {
+        }
 
         $this->io = $prevIO;
         $this->outputProgress = $prevProgress;
 
+        if ($e) {
+            throw $e;
+        }
+
         return trim($output);
     }
 }