Istanbul code coverage for Mocha tests

Question

I am trying to get Istanbul to work.

I keep getting this message at the end of running istanbul:

No coverage information was collected, exit without writing coverage information

I have tried everything I could find online as you can see:

      "scripts": {
        "start": "node ./bin/start.js",
        "test": "mocha test --no-timeouts",
        "debug_mocha": "node-debug --no-timeouts _mocha",
        "eslint": "eslint .",
        "jshint": "jshint --exclude ./node_modules .",
        "istanbul": "istanbul cover --include-all-sources --hook-run-in-context node_modules/.bin/_mocha -- -u exports -R spec test/**/*",
        "istanbul2":"istanbul cover node_modules/.bin/_mocha -- -u exports -R spec test/**/*",
        "istanbul1":"istanbul cover node_modules/.bin/_mocha -- test/**/*",
        "istanbul0":"istanbul cover _mocha test/**/*.js",
        "istanbul3":"istanbul cover _mocha -- -R spec --recursive test"
      }

my .istanbul.yml file is at the root of the project and looks like istanbul is picking it up successfully.

//.istanbul.yml
    instrumentation:
      compact: false
      save-baseline: true
    reporting:
      reports:
        - lcov
        - cobertura

What am I missing?

Answer 1

Got it, finally.

https://github.com/gotwarlost/istanbul/issues/44#issuecomment-57708358 says:

Using _mocha directly does not work on windows. Please use the full path to the JS file instead

Then, after a little experimentation, victory:

istanbul cover C:/dev/my_project/node_modules/mocha/bin/_mocha --