1 Phase Testing

\ 2 Overview of Implementation phase Create Class Skeletons Define Implementation Plan (+ determine subphases) Define Coding Standards For each subphase Implement Methods in class/es Code review Unit test Create integration Test plan Create unit Test plans Release unit for integration Integration Testing System Testing Create system Test plan

\ 3 Review: Selecting Glass box test cases  Determine what to test (select types of coverage)  Create a flowchart for code to be tested  Select test cases such that  For a method with only sequential statements, 100% statement coverage will be achieved  For a method with sequential statements and branches 100% branch coverage will be achieved in addition to 100% statement coverage  For a method that also includes iterative statements try to approach 100% path coverage as closely as possible with a reasonable number of tests. (assure statement and branch coverage)

\ 4 Black Box Testing  We treat software system as a black box  We cannot see inside, i.e., we knows nothing about  source code  internal data  design documentation  So what do we know then?  Public interface of the function or class (methods, parameters)  Class skeleton (pre and post conditions, description, invariants)  Test cases are selected based on  input values or situation  expected behaviour and output of methods

\ 5 Select Set of Test Cases using Black Box Testing Strategy 1. Determine what to test  Which method of which class, type of test 2. For each parameter and object a) Establish the parameters equivalence classes OR consider that various states of object  Determine all valid (invalid) values or all ranges of valid (invalid) values, and boundaries between those ranges.  Determine valid and invalid states of objects (preconditions) b) Select representative values for each equivalence class (one from each range, and boundary values) to use as basis of your test cases

\6 Example Test case: (from text)  Code being tested:  Method in a board game. setDot(…)  Turns dots in a grid on and off  Assuming that the grid is to be 15 by 15

\ 7 From Skeleton: setDot(int i, int j, int c) Public void setDot( int i, int j, int c) // send message to the Graphical_Cell object which is the //element at row i and column j in the grid array. Set the // dot to color c. i and j are both less than 15 //precondition: the 2_D array of Graphical_Cell objects //has been instantiated. c has value 1 or 2 //postcondition: Graphical_Cell object shows that a dot at //row i and column j is displayed with color c.  Use the information -1 < i,j < 15, and 0 < c < 3 to define equivalence classes for the variables  Use the information Graphical_Cell object has been instantiated to define equivalence classes for object Graphical_Cell

\ 8 Equivalence classes for c, i and j  3 equivalence classes have been defined for each variable. Each colored bar shows one equivalence class. The equivalence classes define where each variable is valid and invalid.  Next, the equivalence classes can be used to help choose test values for each variable 0-14 >14 ijc <0 validinvalid 0-14 >14<0 valid invalid 1-2 >2 <1 validinvalid

\ 9 Choosing Representative test values i, j  How to choose representative values for tests based on equivalence classes:  Consider variables i and j:  Choose one value from each equivalence class for i -3, 6, 18  Choose one value from each equivalence class for j -4, 8, 17  Choose boundary values between each pair of equivalence classes, -1, 0 and 14, 15. For variables i and j use test values  i: -3, -1, 0, 6, 14, 15, 18  j: -4, -1, 0, 8, 14, 15, >14 i or j <0 validinvalid

\ 10 Choosing Representative test values c  Consider variable c  Choose one value from each equivalence class -2, 2, 5  Choose boundary values between each pair of equivalence classes, 0,1 and 2, 3.  For variable c use test values  -2, 0, 1, 2, 3, >2 i or j <1 validinvalid

\ 11 Choosing Representative test values Graphical_Cell Not instantiated Graphical_Cell Graphical_Cell has two possible states, instantiated (consistent with precondition) or not instantiated (inconsistent with precondition) Each colored bar shows one equivalence class instantiated valid invalid

\ 12 Equivalence classes for grid or Graphical_Cell Not instantiated Graphical_Cell Consider the object, Graphical_Cell. has two possible states, instantiated, not instantiated In designing test cases use two possible states, instantiated, not instantiated instantiated valid invalid

\ 13 What test values have we selected?  For variable i use test values  -3, -1, 0, 6, 14, 15, 18  For variable j use test values  -4, -1, 0, 8, 14, 15, 17  For variable c use test values  -2, 0, 1, 2, 3, 5  For object, Graphical_Cell.  instantiated, not instantiated  For optimal testing coverage we would use all possible combinations of these values (2*6*7*7=588 tests).  In practice will usually choose a subset of possible combinations which reflects the best test coverage with a more reasonable number of tests.

\ 14 Choosing a subset: an example  You may wish to consider the following  Testing with all valid variables and preconditions  Testing with all valid variables and only one invalid precondition (for each precondition in turn)  Testing with all valid preconditions and one invalid variable (for each variable in turn, one sample from each invalid equivalence class)  Testing with all valid preconditions and a boundary value for each variable  Testing with pairs of invalid variables?  What else is needed ?

\ 15 Proposed subset - 1  1 -- All variables in the valid range  i=6 j= 8 c = 1 Graphical_ Cell instantiated  2 -- All variables in the valid range  i=6 j= 8 c = 1 Graphical_ Cell not instantiated  3 – i, and c valid j invalid  i=6 j= 17 c = 1 Graphical_ Cell instantiated  4 – i, and c valid j invalid (different equivalence class value)  i=3 j= -4 c = 1 Graphical_ Cell instantiated  5 -- j, and c valid i invalid  i=-3 j= 8 c = 1 Graphical_ Cell instantiated  6 -- j, and c valid i invalid  i=18 j= 8 c = 1 Graphical_ Cell instantiated

\ 16 Proposed subset - 2  7 -- i, and j valid c invalid  i=6 j= 8 c = 5 Graphical_ Cell instantiated  8 -- i, and j valid c invalid  i=6 j= 8 c = -2 Graphical_ Cell instantiated  9 – i, and c valid j invalid  i=15 j= 14 c = 1 Graphical_ Cell instantiated  10 – i, and c valid j invalid (different equivalence class value)  i=14 j= 15 c = 1 Graphical_ Cell instantiated  j, and c valid i invalid  i=-1 j= 0 c = 2 Graphical_ Cell instantiated  j, and c valid i invalid  i=0 j= -1 c = 2 Graphical_ Cell instantiated

\17 Proposed subset - 3  i, and j valid c invalid  i=0 j= 14 c = 0 Graphical_ Cell instantiated  i, and j valid c invalid  i=14 j= 0 c = 3 Graphical_ Cell instantiated  15 – i, and c valid j invalid  i=0 j= 14 c = 1 Graphical_ Cell instantiated  16 – i, and c valid j invalid (different equivalence class value)  i=14 j= 0 c = 2 Graphical_ Cell instantiated

\ 18 Test Case Example  Test id - 1  Test purpose: Unit test Game2DClient class method setDot( ) (page271) using Black box testing strategy  Requirement # 4  Inputs: i = 6, j = 8, c = 1 (blue), grid has been instantiated  Testing procedure:  Create an object of Game2DClient class type  Show grid (to demonstrate dot is not set before call to setDot)  Call setDot( i = 6, j = 8, c = 1 )  Evaluation: Show grid  Expected behaviours and results: blue dot now showing at location (6, 8) on grid  Actual behaviours and results:

\ 19 Test Case Example  Test id - 2  Test purpose: Unit test Game2DClient class method setDot( ) (page271) using Black box testing strategy  Requirement # 4  Inputs: i = 6, j = 8, c = 1 (blue), grid has NOT been instantiated  Testing procedure:  Create an object of Game2DClient class type without a grid  Call setDot( i = 6, j = 8, c = 1 )  Evaluation: no step required  Expected behaviours and results: message stating that grid does not exist  Actual behaviours and results:

\ 20 Test Case Example  Test id - 11  Test purpose: Unit test Game2DClient class method setDot( ) (page271) using Black box testing strategy  Requirement # 4  Inputs: i = -1, j = 0, c = 2 (blue), grid has been instantiated  Testing procedure:  Create an object of Game2DClient class type  Show grid (could set other dots)  Call setDot( i = -1, j = 0, c = 2 )  Evaluation: Show grid  Expected behaviours and results: grid should be unchanged and a message stating that the location for the new blue dot is erroneous  Actual behaviours and results: