QA and Testing
QA Activity







Processes monitoring
Standards compliance monitoring
Software testing
Infrastructure testing
Documentation testing
Usability testing
Sign off to production
Types of software testing
Unit Testing
Functional Testing
Security Testing
Load testing
Performance testing
Regression Testing
User Acceptance Test
Functional testing activity







Requirements development
Test Cases development
Defects discovering – testing
Defects tracking
Defects evaluating
Defects reporting
Regression testing
Defects





Tracking
Evaluating
Reporting
Defect Severity
Defect Priority
Defect Reporting Procedure






Fill in Actual Result
Gather the evidences
Fix the day and time
Define Severity and Priority
Notify developer
Make the record in Defect Tracking
Database
Defect Severity




Critical
Major
Minor
Trivial
Defect Priority




Emergency
High
Medium
Low
Test Plan Objectives




Identify the requirements
Identify Defect Reporting Procedure
Define Test Entry and Text Exit
Test Cases
Test Case

Implementation scenario that has or does:





Reasonable probability to catch an error
Define exactly the input
Define exactly expected result
Predict an error
Predict system behavior
Test Cases Main Types


Positive
Negative
Equivalence classes
All test cases all test the same things
 If one test catches a bug, the others
probably will too
 If one test does not catches a bug, the
others probably won’t either

To determine equivalence classes look for:
The test cases involve the same input
variables
 They result in similar operations in the
program
 They affect the same output variables
 None force the program to do error
handling or all of them

Common Software errors








Functional
Boundary related
Calculation
Initial and Later States
Control Flow
Error in Handling and Interpreting Data
Race Conditions
Load conditions
Common Software errors

Functional

Check if the system functions are
implemented correctly
Common Software errors



Boundary related
Boundaries often are numeric, but not
neceserily. In general that is the question
of belonging to some domain.
Check the system behavior when the
value fits the boundary, is below the
boundary, and is above it.
Common Software errors

Calculation


Errors may be in the formula
Also there may be lost of calculation precise
due to of roundoff or truncation
Common Software errors

Initial and later state






Failure to set a data item to 0
Failure to initialize a loop-control variable
Failure to initialize pointers
Failure to clear a string
Failure to initialize a register
Failure to clear flag
Common Software errors

Control flow




Not correct if .. then.. Else
GOTO somewhere
Logic errors
Return to wrong place
Common Software errors

Race conditions




Races in updating data
Assumptions that one event will finish before
the other begins
Assumption that an input will not occur during
some short interval
Options out of synch during a display change.
Common Software errors

Load conditions





Required resources are not available
Resources are not released
Not available large memory area
Does not clean items from queue, buffer, or
stack
Lost messages
Data boundaries






Unterminated null terminated strings
R/W past end of data structure, or an
element on it
Read outside a message buffer
Value stack under/overflow
Message sent to wrong process or port
Failure to validate incoming messages
Exercise




Review the description of errors assigned
to you
Review use cases relevant to your miniproject and think about writing the code to
implement business logic
Determine cases where a software error
potentially can manifest itself
Make your notes and inform the class
Assignment








– boundary errors, calculation errors (pp 399-403)
– Race conditions (pp 421-423)
– Initial and later state (403-406)
– loops & other control flow (pp 411-415)
– Control flow (pp 406-411)
– errors in handling and interpreting data (pp 416-418)
- Load conditions (pp 423-425)
– Data boundaries & messaging problems (pp 418-420)
Presentation tips





Outline your mini-project content
Present your use cases with your mock-up screens
Present major items of your “software errors” part
Talk about applicability –
 What errors may occur and when
Prepare written help to show on the screen