CFG (Control Flow Graph)

What is a Control Flow Graph?

A Control Flow Graph (CFG) is a graphical representation of all the paths that might be traversed through a program during its execution, using nodes and edges.

Key Elements of a CFG

• Nodes: Represent statements or blocks of sequential code.
• Edges: Represent the flow of control between nodes (e.g., following an if/else branch or a loop).
• Decision Points: Nodes with more than one outgoing edge, representing branching logic.

Why CFGs Matter for Testing

CFGs are the foundation for structure-based testing techniques like statement, branch, and path coverage, and are used to calculate cyclomatic complexity and design basis path test cases.