Update Unpacker.php

read the json file once

Author: Gemorroj

src/Unpacker.php

@@ -115,6 +115,7 @@ public function unpack(Operation $op, Result $result = null): Result
     public function updateLock(Result $result, IOInterface $io): void
     {
         $json = new JsonFile(Factory::getComposerFile());
+        $jsonContent = file_get_contents($json->getPath());
         $manipulator = new JsonConfigSource($json);
         $locker = $this->composer->getLocker();
         $lockData = $locker->getLockData();
@@ -135,7 +136,7 @@ public function updateLock(Result $result, IOInterface $io): void
         }
         $lockData['packages'] = array_values($lockData['packages']);
         $lockData['packages-dev'] = array_values($lockData['packages-dev']);
-        $lockData['content-hash'] = $locker->getContentHash(file_get_contents($json->getPath()));
+        $lockData['content-hash'] = $locker->getContentHash($jsonContent);
         $lockFile = new JsonFile(substr($json->getPath(), 0, -4).'lock', null, $io);
 
         if (!$this->dryRun) {
@@ -144,9 +145,9 @@ public function updateLock(Result $result, IOInterface $io): void
 
         // force removal of files under vendor/
         if (version_compare('2.0.0', PluginInterface::PLUGIN_API_VERSION, '>')) {
-            $locker = new Locker($io, $lockFile, $this->composer->getRepositoryManager(), $this->composer->getInstallationManager(), file_get_contents($json->getPath()));
+            $locker = new Locker($io, $lockFile, $this->composer->getRepositoryManager(), $this->composer->getInstallationManager(), $jsonContent);
         } else {
-            $locker = new Locker($io, $lockFile, $this->composer->getInstallationManager(), file_get_contents($json->getPath()));
+            $locker = new Locker($io, $lockFile, $this->composer->getInstallationManager(), $jsonContent);
         }
         $this->composer->setLocker($locker);
     }