Frequent contributor Argle Bargle (recently, or even in last week’s Errord) works with a programmer called “Jimbo”. Jimbo is a solid co-worker and a good programmer. He has more tenure at the company than Argle, which means Jimbo is who Argle goes to when he has questions.
Recently, Argle worked his way through a rather complicated bit of code. It involved passing data between two different languages inside of a real-time system. Much of its functionality was opaque and complicated, so Argle wrote literal paragraphs of documentation explaining what the code did, how to invoke it, what the gotchas might be, and how to avoid them.
Argle expected the pull request to take some time to complete, but Jimbo was on the spot and approved it quickly. Another reviewer chimed in, and in went the code.
The next day, Argle and Jimbo were working together through some fresh code which depended on that request.
“Wait a second,” Jimbo asked, “how does this data make it from one thread to another? It’s mallocd. I don’t see how it gets past that boundary.”
“You realize,” Argle replied, “I documented this, in detail, in the code you reviewed yesterday afternoon.”
“Oh, that? I didn’t read it.”
“That defeats the purpose of code reviews.”
Jimbo shrugged. “I’m sure it’s fine.”
Argle writes:
I have worked in two aerospace firms in my life and there are days I wonder that I risk setting foot in an airplane.