The 9 Causes of software errors ( Deliberate deviations from software…
The 9 Causes of software errors
1.Faulty requirements definition
the root cause of software errors
Inclusion of unneeded requirements
Incorrect requirement definitions
Deliberate deviations from software requirements
Overtly omit functionality duo time/budget pressure.
Inserting unapproved enhancements.
Reused code Contains unneeded/unusable code.
Reuse previous/similar work to save time.
Ignore seemingly minor features, which sometimes are quite major.
Logical design errors
Erroneous definition of boundary condition
A common source of errors
Omission of required system state
Procedures specified by systems analyst not accurate reflection of the business process specified.
Omission of definition concerning reactions to illegal operation of the software system.
Coding errors (too many to try to list)
Logic errors (Program runs; results wrong)
Run-time errors (Crash during execution)
Syntax error (Grammatical errors)
Client-developer communication failures
Lack of attention
by client to developer questions
by developers dealing with req. & changes
talented individuals come from different planets!
Written changes during development
Oral changes during Developments
Instructions in req. doc.
Clients -> users & Developers -> different mindset entirely some times
Non-compliance documentation & coding instructions
Not only execution software but coding standards; manuals, messages displayed , resources needed.
Shortcomings of the testing process
failure to quickly correct detected faults duo to unclear indications that there was a fault.
Failure to fix the errors duo to time constraints
Failure to document, report detected errors and faults
Incomplete test plans
User interface and procedure errors
If the Interface is unsatisfactory, this view will be absolutely conveyed ‘up the line.’
Errors in the documentation within the software "User manual"
Errors in online help (if available)
Errors in the design documents
Listing of non-existing functions (Planned but dropped)
Many Error messages are meaningless
Definitions of Software errors
Syntax (grammatical) error
Logic error (multiply vice add two operands)
Made by programmer
That part may not be executed.
an error is presented but not encountered.
Software errors may not cause software faults.
Fault becomes Failure when/if it is activated
Faults my be found due to software execution or other constraints, such as execution options
Some runs result in failures; some not
The defect testing process
3.Run program with test data -> Test Results
Compare test results to test cases -> Test report
2.Prepare test data -> Test Data
1.Design test cases -> Test cases