Modern C++ Programming with Test-Driven Development

Tests Come FIRST

Wondering if you’ve built a good unit test? Vet it against the FIRST mnemonic, devised by Brett Schuchert and Tim Ottinger. The mnemonic reminds you of a key part of TDD’s definition: tests come first.

FIRST breaks down into the following:

• F for Fast

• I for Isolated

• R for Repeatable

• S for Self-verifying

• T for Timely

Fast

TDD supports incremental and iterative development through its core cycle of specify, build, and refactor. How long should a cycle take? The shorter, the better. You want to know as soon as your code either doesn’t work or breaks something else. The more code you grow between introducing a defect and discovering it, the more time you stand to waste in pinpointing and fixing the problem. You want ultra-rapid feedback! ...