Code Coverage in TESSY

A test object is considered to consist of items like branches, conditions, etc. Code coverage measures, how many of the items were exercised during the tests. This number is related to the total number of items and is usually expressed in percent.

TESSY features

  • Entry Point Coverage
  • Statement Coverage
  • Branch Coverage
  • Decision Coverage
  • Modified Condition / Decision Coverage (MC/DC)
  • Multiple Condition Coverage
  • Function Coverage

Branch Coverage

Branch coverage is usually abbreviated “C1”.

Roughly spoken:

Branch Coverage reveals, if all branches were executed. (For example, an if-instruction has two branches, the then-branch and the else-branch.)

Modified Condition / Decision Coverage (MC/DC)

MC/DC coverage takes the structure of a decision into account.

Each decision is made up from conditions, which are combined by logical operators (and, or, not).

Roughly spoken, to get 100% MC/DC for a decision, each condition in the decision requires a pair of test cases, that

  • Differs in the Boolean value for that condition, and
  • Has the same Boolean value for all other conditions, and
  • Produces true and false in the outcome of the whole decision

n conditions require n+1 test cases

Multiple Condition Coverage (MCC)

MCC coverage takes the structure of a decision into account.

Each decision is made up from conditions, which are combined by logical operators (and, or, not).

Roughly spoken, to get 100% MCC for a decision, all combinations of true and false for the conditions in the decision have to be evaluated.

Summaries of coverage

A summary of the achieved coverage information for all coverage measures is included in:

  • The standard test report for the test object in question
  • The batch test report for several test objects