public function testFileUpdateStream() { $prophecy = $this->prophesize('League\\Flysystem\\FilesystemInterface'); $prophecy->updateStream('path.txt', 'contents')->willReturn(true); $filesystem = $prophecy->reveal(); $file = new File(null, 'path.txt'); $file->setFilesystem($filesystem); $output = $file->updateStream('contents'); $this->assertTrue($output); }