Can anyone tell me which is better, code coverage or test coverage?
There isn’t a definite answer to this, as it totally depends on type of your project and the complexity it has.
If you have to look on the impact of code coverage and test coverage to identify which is better, they are measured totally different! Code coverage is measured by the percentage of code that is covered during testing, whereas test coverage is measured by the features that are covered via tests.
So it’s important to understand that these are different approach towards testing, and totally depends on the scope of your project whether White Box (code coverage) or Black Box (test coverage) is better! However the ultimate goal should be to get maximum coverage for thorough testing of code and product!
Better to understand the advantages/disadvantages of these approaches and how they would fit in your project! To deep dive into code coverage vs test coverage you can read the blog here 