Computing Science Software Design and Development Testing and

Computing Science Software Design and Development Testing and Documenting Solutions

Learning Objectives By the end of this topic you will be able to: • construct a test plan; • explain the difference between syntax, execution and logic errors; • understand how dry runs, trace tables, trace tools and breakpoints are used in the debugging process.

Test plans A test plan is a set of test data that will systematically and comprehensively test a piece of software It is used to ensure that the software meets the original specification The test plan should be created in the design stage

Test plans should include • • Original software specification Testing schedule Aspects to be tested The test data and expected resultssting

Types of errors • Syntax error - the "grammatical" rules of the language have been broken. It is normally detected spotted by a compiler or interpreter. • Logic error - the program runs but does not do what the programmer intended. • Execution error - the program crashes when it is run

Debugging methods • Dry run – a manual (pencil and paper) run through of the program, • Trace table – used in dry runs to keep a note of the values of variables as you go through the program • Breakpoints – setting a point in the code where it will stop and the value of variables can be examined • Trace tools – allows programmer to see what lines of code are being executed and what variables are changing