LCOV

LCOV, the Linux Test Project gcov extension, is a tool to manipulate and display information about which parts of a program are actually executed, or covered, while running a test case or a set of test cases.

It consists of a set of Perl scripts that build on the text output of coverage tools such as gcov, llvm-cov, Coverage.py, Cobertura, Devel::Cover or JaCoCo. Its genhtml command produces hyperlinked HTML reports where coverage rates are shown with bar graphs and colours, with overview pages for large projects. Coverage data from several runs can be merged, filtered and compared, for example to show differential coverage between two versions of the code. The LCOV tracefile format it introduced is understood by many other tools.

LCOV is free and open source under the GPL-2.0 licence.