Test Case Concept

With test cases made known to Testwell CTC++, the counter data can be written in separate datafiles.

The instrumented program is assumed to contain a test driver portion. It can be instrumented or not. The test driver calls the code under test, the instrumented code. In the test driver, the tests can be grouped to test cases, and the coverage can be measured per test case.

The Testwell CTC++ runtime library API has a function with the following prototype:

void ctc_set_testcase(const char* tcname);

In the test driver, you call this function when a new test case starts, handing over a proper name for the test case. With that separation, several datafiles are written containing the coverage data of the corresponding test case.

Example: If you name the test cases "tc01", "tc02" and "tc03", three or four datafiles are created: MON.dat (if there is some coverage data collected before the first test case starts), MONtc01.dat, MONtc02.dat and MONtc03.dat.

Test case specific coverage reports are obtained by ctcpost from MON.sym and one of the MONtc<n>.dat.

A coverage report for the whole test session is obtained from MON.sym and all MONtc*.dat.

Note: The user has to take care that the test case names lead to valid file names (length, acceptable characters).

Instead of calling ctc_set_testcase(“tcname”) directly, you can also use a pragma:

#pragma CTC TESTCASE tcname

If the test driver code is compiled without instrumentation, the file still compiles, and the line has no effect.

In practical programs (test drivers, which necessarily are not instrumented), it is perhaps best to write a prototype for ctc_set_testcase(), and then call it explicitly. Then you can also pass the test case name via a variable of type char *, while in the #pragma style a variable cannot be used.

Note: If the code is instrumented for timing and if at the time of ctc_set_testcase() call there are "open functions" (the instrumented function has been entered, but not yet exited), the timing data in the datafiles is not correct for these functions.