public function testStaticFlow() { $file = $this->makeFile('head/static', "line 1\nline 2\nline 3"); $flow = Flow::head(1); $output = $flow->flow($file); static::assertNotSame($file, $output); static::assertInstanceOf(LocalFile::class, $output); static::assertEquals(["line 1"], $output->getContents()); }