Let’s start with a bold statement: We all love to write unit great tests for our code. More or less. — Unknown Programmer Writing unit tests for my code mostly follows this pattern Write a test and make it fail (red) Write the function to fix the test (implement function) Start over with step 1 For one of my projects, I was using jest. It’s fast now, and it has several features that I highly value.

I was building a Reactjs component, that should toggle between two child components. <Toggle> <Comp1> <Comp2> </Toggle> The render method of Toggle looked like this render() { const content = React.Children.count(this.props.children) > 0 ? this.props.children[0] : this.props.children[1]; return ( ${content} ); } Unfortunately, this didn’t work (index out of bounds), when I passed only one component instead of two. This doesn’t make sense since the Toggle is supposed to toggle between two components.

I was testing an ant based build script change today. And I thought ant was already retired. Running the script led to a lot of warnings about a missing library. I asked the person, if there are any dependencies for ant-contrib. His response was “yes, you need to install ant-contrib”. First of all, I didn’t have ant installed. But that was easy with irichter@irichter-MacBookPro:~ brew2 install ant Unfortunately, ant-contrib wasn’t available via homebrew, so I had to download it and place it… where?