add test for updating etag with unchanged mtime in child folder

Signed-off-by: Robin Appelman <robin@icewind.nl>

tests/lib/Files/Cache/ScannerTest.php

@@ -423,4 +423,29 @@ public function testNoETagUnscannedFolder() {
 		$newFolderEntry = $this->cache->get('folder');
 		$this->assertNotEquals($newFolderEntry->getEtag(), $oldFolderEntry->getEtag());
 	}
+
+	public function testNoETagUnscannedSubFolder() {
+		$this->fillTestFolders();
+		$this->storage->mkdir('folder/sub');
+
+		$this->scanner->scan('');
+
+		$oldFolderEntry1 = $this->cache->get('folder');
+		$oldFolderEntry2 = $this->cache->get('folder/sub');
+		// create a new file in a folder by keeping the mtime unchanged, but mark the folder as unscanned
+		$this->storage->file_put_contents('folder/sub/new.txt', 'foo');
+		$this->storage->touch('folder/sub', $oldFolderEntry1->getMTime());
+
+		// we only mark the direct parent as unscanned, which is the current "notify" behavior
+		$this->cache->update($oldFolderEntry2->getId(), ['size' => -1]);
+
+		$this->scanner->scan('');
+
+		$this->cache->inCache('folder/new.txt');
+
+		$newFolderEntry1 = $this->cache->get('folder');
+		$this->assertNotEquals($newFolderEntry1->getEtag(), $oldFolderEntry1->getEtag());
+		$newFolderEntry2 = $this->cache->get('folder/sub');
+		$this->assertNotEquals($newFolderEntry2->getEtag(), $oldFolderEntry2->getEtag());
+	}
 }