What does code coverage measure?

Code coverage is a software testing metric that quantifies the extent to which the code of a program is tested by automated tests. It specifically measures how many lines, branches, or paths of the source code have been executed by the test suite. This helps developers and testers understand which parts of the code are being exercised by their tests and, conversely, which parts are not covered.

By focusing on the degree to which the system under test has been exercised, teams can identify gaps in their testing efforts, leading to better test coverage and, ultimately, higher quality software. A higher code coverage percentage typically indicates that a larger portion of the code has been validated against test cases, reducing the risk of undetected bugs.

In contrast, the other options relate to different concepts in software quality assurance and development. The number of bugs found speaks to the quality of the code rather than the effectiveness of the tests. The total lines of code written provides some context about the project's size but does not reflect how well it has been tested. The percentage of automated tests is useful information but does not directly measure the effectiveness of those tests concerning the code base itself.