Turning on code coverage

The code coverage report option is not turned on by default because code coverage data collection incurs a performance penalty. You can turn on code coverage in the build target's scheme.

Click on the helloWorldPackageTests build target:

Then select the Edit Scheme option from the pull-down menu:

Choose the Test option from the left panel and enable the checkbox for the Gather coverage for all targets option at the bottom of the right panel: