Merge coverage files with istanbul

I have a situation where all my tests run in parallel and it creates the coverage report.

I was able to create a separate coverage folder for each test with the --dir option in the command line, which is great.

Now that I have all of these folders with coverage details, is it possible to merge all of these files into one?

Answer

I’ve discovered that istanbul report does the merging of the files by default, which is what I was after.