PHPUnit code coverage ignoring laravel controller public functions

Question

In a current project we are trying to always maintain 100% test coverage for our Laravel 5.3 application. The other day I noticed something weird though. For some reason in controllers any code that is not run, is not flagged as missing a test. However, if I add a function to a model and forget to write a test for it shows up as code missing testing. Here is an example code coverage report for a model:

Here is an example code coverage report for a controller:

You can see in a functional test I test an endpoint that calls the destroy() function at the top, however I forgot to write a test for the endpoint that calls answer(). Why does this not get flagged as code that is not covered?

Simply running:

phpunit --coverage-html ./storage/logs/phpunit

Also here is my phpunit.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<phpunit backupGlobals="false"
         backupStaticAttributes="false"
         bootstrap="bootstrap/autoload.php"
         colors="true"
         convertErrorsToExceptions="true"
         convertNoticesToExceptions="true"
         convertWarningsToExceptions="true"
         processIsolation="false"
         stopOnFailure="false">
    <testsuites>
        <testsuite name="Application Test Suite">
            <directory suffix="Test.php">./tests</directory>
        </testsuite>
    </testsuites>
    <filter>
        <whitelist processUncoveredFilesFromWhitelist="true">
            <directory suffix=".php">./app</directory>
        </whitelist>
    </filter>
</phpunit>

UPDATE:

I think I may have figured out how to fix the issue. In the phpunit.xml change processUncoveredFilesFromWhitelist="true" to false. Unforuntuately, the test takes about 3 times as long to run but it seems to flag everything that isn't executed.