how to ensure 100% code coverage of git commits with grunt-mocha-cov

Question

I am trying to set up a continuos integration environment (using quick build) wherein on every commit to a git branch I want to run our test suite, check code coverage and revert commits if either the test fails or the code coverage is below a certain threshold. In particular I want to ensure that the code I am checking in is 100% tested. Our test suite has been set up using grunt and mocha-hack and we are using grunt-mocha-cov for coverage. But grunt-mocha-cov instruments the whole source code. I want only the git diffs to be instrumented. Is there a way to do this?

Answer 1

There is a tool named diff-cover, which can check coverage for git diffs. It takes Cobertura XML coverage reports and compares with the output of git diff. It then reports coverage information for lines in the diff.

I cannot see whether grunt-mocha-cov is able to output Cobertura reports, but you should be able to find some grunt plugin that does.

Note that diff-cover doesn't help you to avoid unneccessary coverage instrumentation for performance reasons.