Control Flow Graph

• A Control Flow Graph (CFG) models all executions of a method by describing control structures.
• Nodes: Statements or sequences of statements (basic blocks).
• Basic Block: A sequence of statements such that if the first statement is executed, all statements will be (no branches).
• Edges: Transfer of control from one statement to the next.
• CFGs are often annotated with extra information to model data:
  • Branch predicates.
  • Defs and/or uses.

Graph Coverage Criteria: Applied to test code

Structural Graph Coverage Criteria

CFG: If statement

CFG: If statement with return

CFG: Switch case

CFG: While Loop

CFG: For Loop