Do not update mime types for folders with extension

Some folders might have an extension like "test.conf".
This fix prevents to overwrite the folder's mime type with another mime
type while running the mimetype repair step.

lib/repair/repairmimetypes.php

@@ -35,6 +35,11 @@ class RepairMimeTypes extends BasicEmitter implements \OC\RepairStep {
 	 */
 	protected $config;
 
+	/**
+	 * @var int
+	 */
+	protected $folderMimeTypeId;
+
 	/**
 	 * @param \OCP\IConfig $config
 	 */
@@ -91,7 +96,7 @@ class RepairMimeTypes extends BasicEmitter implements \OC\RepairStep {
 		return \OC_DB::prepare('
 			UPDATE `*PREFIX*filecache`
 			SET `mimetype` = ?
-			WHERE `mimetype` <> ? AND `name` ILIKE ?
+			WHERE `mimetype` <> ? AND `mimetype` <> ? AND `name` ILIKE ?
 		');
 	}
 
@@ -124,6 +129,10 @@ class RepairMimeTypes extends BasicEmitter implements \OC\RepairStep {
 	}
 
 	private function updateMimetypes($updatedMimetypes) {
+		if (empty($this->folderMimeTypeId)) {
+			$result = \OC_DB::executeAudited(self::getIdStmt(), array('httpd/unix-directory'));
+			$this->folderMimeTypeId = (int)$result->fetchOne();
+		}
 
 		foreach ($updatedMimetypes as $extension => $mimetype) {
 			$result = \OC_DB::executeAudited(self::existsStmt(), array($mimetype));
@@ -139,7 +148,7 @@ class RepairMimeTypes extends BasicEmitter implements \OC\RepairStep {
 			$mimetypeId = $result->fetchOne();
 
 			// change mimetype for files with x extension
-			\OC_DB::executeAudited(self::updateByNameStmt(), array($mimetypeId, $mimetypeId, '%.' . $extension));
+			\OC_DB::executeAudited(self::updateByNameStmt(), array($mimetypeId, $this->folderMimeTypeId, $mimetypeId, '%.' . $extension));
 		}
 	}
 

tests/lib/repair/repairmimetypes.php

@@ -514,5 +514,22 @@ class RepairMimeTypes extends \Test\TestCase {
 
 		$this->renameMimeTypes($currentMimeTypes, $fixedMimeTypes);
 	}
+
+	/**
+	 * Test that mime type renaming does not affect folders
+	 */
+	public function testDoNotChangeFolderMimeType() {
+		$currentMimeTypes = [
+			['test.conf', 'httpd/unix-directory'],
+			['test.cnf', 'httpd/unix-directory'],
+		];
+
+		$fixedMimeTypes = [
+			['test.conf', 'httpd/unix-directory'],
+			['test.cnf', 'httpd/unix-directory'],
+		];
+
+		$this->renameMimeTypes($currentMimeTypes, $fixedMimeTypes);
+	}
 }