title: .NET Core 2.2: xUnit Theory Inlinedata not working with enum values
body: <p>Does anybody know how to use xUnit with "Theory" and "InlineData" with <code>enum</code> values? This here is leading to the tests not being recognized as tests and not run:</p>
  
  <pre><code>[Theory]
  [InlineData("12h", 12, PeriodUnit.Hour)]
  [InlineData("3d", 3, PeriodUnit.Day)]
  [InlineData("1m", 1, PeriodUnit.Month)]
  public void ShouldParsePeriod(string periodString, int value, PeriodUnit periodUnit)
  {
      var period = Period.Parse(periodString);
      period.Value.Should().Be(value);
      period.PeriodUnit.Should().Be(periodUnit);
  }
  </code></pre>
  
  <p>The tests work and run if I use the int values of the enum instead of the enum values.</p>