See [the coverage report](https://codecov.io/gh/shelljs/shelljs/src/c16fb7dac9dfec6cec29cfe633daece83a127d47/src/head.js) We're currently missing line coverage for: - [Unable to open file](https://codecov.io/gh/shelljs/shelljs/src/c16fb7dac9dfec6cec29cfe633daece83a127d47/src/head.js#L22) - Right-hand-side of a pipe ([here](https://codecov.io/gh/shelljs/shelljs/src/c16fb7dac9dfec6cec29cfe633daece83a127d47/src/head.js#L70) and [here](https://codecov.io/gh/shelljs/shelljs/src/c16fb7dac9dfec6cec29cfe633daece83a127d47/src/head.js#L89)) Blocks #671