edgecoverage

Edgecoverage refers to a software testing metric that measures the extent to which the edges of a program's control flow graph have been exercised by test cases. The control flow graph represents the possible paths of execution through a program, with nodes representing statements or blocks of code and edges representing the transitions between them. Achieving 100% edge coverage means that every possible transition between code elements has been executed at least once during testing.

This metric is a more thorough form of structural testing than statement coverage, which only ensures that each line of code has been executed. By focusing on edges, edge coverage also verifies that specific conditions leading to different execution paths have been tested. For example, in an if-else statement, statement coverage might only ensure the if block is executed, while edge coverage would require testing both the condition being true (taking the if path) and the condition being false (taking the else path).

While achieving high edge coverage can increase confidence in the quality of the software by demonstrating that a wide range of program logic has been exercised, it does not guarantee the absence of defects. Certain complex logical paths or data-dependent errors might still exist even if all edges are covered. Therefore, edge coverage is often used in conjunction with other testing techniques and metrics. It is commonly employed in unit testing and integration testing phases.