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100% coverage sounds great, but is it c0, c1, c2, c3 or path coverage ? If you do not know, here is the answer:

• C0 = every instruction
• C1 = every branch if(i=1) a; even if there is no actual instruction in the i!=1 path it needs 2 tests
  1. i = 1
  2. i != 1
• C2 + C3 ~= is every condition inside an ‘if’ is once true and once false (personally, i could not care less…)
• C4: Path-coverage = every possible path was taken, if(a) x else b; if(c) y requires 4 tests
  1. a true c true
  2. a true c false
  3. a false c true
  4. a false c false

Try to aim for ~95% C0 and ~70% C1. C2 and C3 in my opinion add no value(except that they cover more paths) and C4 is often not possible, since a loop can have infinite paths (go through 1,2,3,4… times).