Subject: System Test & Verification
Test Coverage is the technique using which we can determinewhether the test cases formed are covering the application codefully and how much code is covered using the test cases.
Yes, it is usually impossible to test all combinations ofpotential input values in order to guarantee some code is correct.This is because a program can have many forms of inputs and manyforms of outputs. Once the program is in production when the actualusers uses or tests the software, then there can be various resultsbased on various inputs. Thus, it is usually impossible to test allcombinations of potential input
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