What are the two basic program statements
- Assignment Statements (x = 2 * y;)
- Conditional Statements (if(), for(), while(),…)
What is control flow?
Successive execution of program statements where conditional statements alter the default flow
What is a program path?
Sequence of statements from entry to exit
What are the assumptions for control flow?
- We have correct specifications
- Definitions of data are correct
- Data can be accessed correctly
- All know bugs have been resolved
What drives the control flow?
The logic in the code
What is a control flow graph?
It is a graphical representation of a program’s control structure
What is a complete path?
Path that goes from the beginning of the program to the end of the program
Why are complete paths useful?
They are useful because we can’t start execution randomly wherever we want w/out modifying the code
What do the different symbols in control graph mean?
- Diamond (Decision point) - where control can diverge
- Square (Process block) - statements uninterrupted by decisions or junctions
- Circle (Junction point) - where control flow merges
Why are complete paths interesting?
Complete path are the only paths that are able to be executed without changing code
What is complete testing in Control Flow testing?
- Path Coverage
- Statement Coverage
- Branch Coverage
What is path coverage?
Every complete path (start to end) executed
What is statement coverage?
Every line/statement executed at least once and observing the output
What is branch coverage?
Every branch (true/false of every decision) executed at least once
What are the two types of paths?
- Executable path - there exists input so that path is executed
- Infeasible path - there is no input to execute the path
What is 100% statement coverage?
All the statements have been executed at least once; Cover all Assignment & Conditional statements
What is 100% branch coverage?
Selecting a set of paths such that each branch is included on some path
What is a predicate? Path predicate?
- A predicate is a logical function evaluated at a decision point
- A path predicate is the set of predicate associated with a path
What is control flow dominated by?
- Statement testing/Coverage
- Branch testing/Coverage
… path coverage has too large of a domain
