QABattle

BDD & TDD / Quiz

Know Your Doubles

Dummy, stub, spy, mock, fake. Five words, five different tools, and a suite that rots when you can't tell them apart.

Difficulty
Hard
Format
Quiz
Points
200
Estimate
12 min

// MISSION BRIEF

Your Mission

Every "mock" in your codebase is actually one of five distinct test doubles, and each solves a different problem. This quiz drills the Meszaros/Fowler taxonomy, state vs behavior verification, and the smell of mock overuse.

Scoring: timed quiz; accuracy first, speed bonus for fast clean runs.

// FIRST CONTACT

Battle teaser

A constructor requires a logger, but the test never exercises logging. You pass a placeholder object that is never called. That double is a:

  1. ADummy: passed to satisfy a signature, never used
  2. BMock
  3. CFake
  4. DStub
Answers, scoring, hints, and the full battle stay sealed.

// SKILL TAGS

test-doublesmockingunit-testingtdd