When people talk about code coverage, the conversation often revolves around achieving a high percentage. But in reality, the number alone doesn’t always reflect true test quality. There are multiple types of coverage metrics, and each tells a different story:
Line Coverage: Measures how many lines of code were executed during tests.
Branch Coverage: Checks whether both true/false paths of conditional statements are tested.
Function Coverage: Ensures that each function or method is invoked at least once.
Path Coverage: Goes deeper by validating different execution paths — often harder to achieve but more meaningful.
A project with 90% line coverage could still miss critical branches that hide bugs. On the other hand, even 70% coverage with strong branch/path tests might give better confidence.
Another interesting trend is the use of tools that generate tests automatically from real user traffic. For example, platforms like Keploy approach coverage not just as a metric, but as a way to uncover untested edge cases that developers may never think of writing manually. It highlights how test generation and coverage can complement each other to ensure better reliability.
