Testing


You should test all of your lines of code
Especially error paths
Really: fake all errors and check the outcome
Whe you have a bug, you can't debug your error management too
Any "if" is one test-run more in your way to delivery

Which doesn't mean I support "test-driven programming"
To be honest, I see the rationale behind TDD
But the true gospel of TDD kills creativity

And please remember to test corner cases
Run-time is the best testing environment
If come scary code is unlikely to run, make it frequent
Scared about overflows? Start at 0xffff
Scared about 64-bit ops? Shift your data up
"I hope it won't happen" leads to failure