[5.7] Fix filesystem locking hangs in PackageManifest::build()

src/Illuminate/Filesystem/Filesystem.php

@@ -2,6 +2,7 @@
 
 namespace Illuminate\Filesystem;
 
+use Exception;
 use ErrorException;
 use FilesystemIterator;
 use Symfony\Component\Finder\Finder;
@@ -122,6 +123,36 @@ public function put($path, $contents, $lock = false)
         return file_put_contents($path, $contents, $lock ? LOCK_EX : 0);
     }
 
+    /**
+     * Write the contents of a file, replacing it atomically if it already exists.
+     *
+     * This will also replace the target file permissions.
+     *
+     * @param string $path
+     * @param string $content
+     * @throws Exception
+     */
+    public function replace($path, $content)
+    {
+        // Just in case path already exists and is a symlink, we want to make sure we get the real path.
+        clearstatcache(true, $path);
+        $realPath = realpath($path);
+        if ($realPath) {
+            $path = $realPath;
+        }
+
+        $dirName = dirname($path);
+        if (! is_writable($dirName)) {
+            throw new Exception("Replacing $path requires it's parent directory to be writable.");
+        }
+
+        // Write out the contents to a temp file, so we then can rename the file atomically.
+        $tempPath = tempnam($dirName, basename($path));
+        file_put_contents($tempPath, $content);
+
+        rename($tempPath, $path);
+    }
+
     /**
      * Prepend to a file.
      *

src/Illuminate/Foundation/PackageManifest.php

@@ -2,7 +2,6 @@
 
 namespace Illuminate\Foundation;
 
-use Exception;
 use Illuminate\Filesystem\Filesystem;
 
 class PackageManifest
@@ -97,7 +96,7 @@ protected function getManifest()
             $this->build();
         }
 
-        $this->files->get($this->manifestPath, true);
+        $this->files->get($this->manifestPath);
 
         return $this->manifest = file_exists($this->manifestPath) ?
             $this->files->getRequire($this->manifestPath) : [];
@@ -164,13 +163,6 @@ protected function packagesToIgnore()
      */
     protected function write(array $manifest)
     {
-        if (! is_writable(dirname($this->manifestPath))) {
-            throw new Exception('The '.dirname($this->manifestPath).' directory must be present and writable.');
-        }
-
-        $this->files->put(
-            $this->manifestPath, '<?php return '.var_export($manifest, true).';',
-            true
-        );
+        $this->files->replace($this->manifestPath, '<?php return '.var_export($manifest, true).';');
     }
 }

tests/Filesystem/FilesystemTest.php

@@ -42,6 +42,16 @@ public function testPutStoresFiles()
         $this->assertStringEqualsFile($this->tempDir.'/file.txt', 'Hello World');
     }
 
+    public function testReplaceStoresFiles()
+    {
+        $files = new Filesystem;
+        $files->replace($this->tempDir.'/file.txt', 'Hello World');
+        $this->assertStringEqualsFile($this->tempDir.'/file.txt', 'Hello World');
+
+        $files->replace($this->tempDir.'/file.txt', 'Something Else');
+        $this->assertStringEqualsFile($this->tempDir.'/file.txt', 'Something Else');
+    }
+
     public function testSetChmod()
     {
         file_put_contents($this->tempDir.'/file.txt', 'Hello World');