if function numval(distance-km) not equal 7703 string "Incorrect distance in kilometers returned - " distance-km delimited by size x"0" delimited by size into errormessage end-string call MFU-ASSERT-FAIL-Z using errormessage end-if
The failed test is rerun, and now passes.
You can incorporate code coverage into your test runs, which shows the range of execution of your source during the test run.