Merge branch '4.4' into 5.1

* 4.4:
  [Filesystem] fix cleaning up tmp files when dumpFile() fails
  [MimeType] Add missing alias for @mime_type

Author: jderusse

Filesystem.php

@@ -658,13 +658,17 @@ public function dumpFile(string $filename, $content)
         // when the filesystem supports chmod.
         $tmpFile = $this->tempnam($dir, basename($filename));
 
-        if (false === @file_put_contents($tmpFile, $content)) {
-            throw new IOException(sprintf('Failed to write file "%s".', $filename), 0, null, $filename);
-        }
+        try {
+            if (false === @file_put_contents($tmpFile, $content)) {
+                throw new IOException(sprintf('Failed to write file "%s".', $filename), 0, null, $filename);
+            }
 
-        @chmod($tmpFile, file_exists($filename) ? fileperms($filename) : 0666 & ~umask());
+            @chmod($tmpFile, file_exists($filename) ? fileperms($filename) : 0666 & ~umask());
 
-        $this->rename($tmpFile, $filename, true);
+            $this->rename($tmpFile, $filename, true);
+        } finally {
+            @unlink($tmpFile);
+        }
     }
 
     /**

Tests/FilesystemTest.php

@@ -1720,6 +1720,18 @@ public function testAppendToFileCreateTheFileIfNotExists()
         $this->assertStringEqualsFile($filename, 'bar');
     }
 
+    public function testDumpRemovesTmpFilesOnFailure()
+    {
+        $expected = scandir(__DIR__, \SCANDIR_SORT_ASCENDING);
+
+        try {
+            $this->filesystem->dumpFile(__DIR__.'/Fixtures', 'bar');
+            $this->fail('IOException expected.');
+        } catch (IOException $e) {
+            $this->assertSame($expected, scandir(__DIR__, \SCANDIR_SORT_ASCENDING));
+        }
+    }
+
     public function testDumpKeepsExistingPermissionsWhenOverwritingAnExistingFile()
     {
         $this->markAsSkippedIfChmodIsMissing();