R package covr: Test Coverage for Packages. Track and report code coverage for your package and (optionally) upload the results to a coverage service like Codecov (http://codecov.io) or Coveralls (http://coveralls.io). Code coverage is a measure of the amount of code being exercised by the tests. It is an indirect measure of test quality. This package is compatible with any testing methodology or framework and tracks coverage of both R code and compiled C/C++/Fortran code.