scalaintellij-ideacode-coverageemma

Partial EMMA code coverage in Scala Case Class for IntelliJ IDEA 10.5

I'm using IntelliJ IDEA 10.5 with the Scala plugin v0.4.1338 updated on August 14th, and Scala 2.9.0.1. I recently began using the EMMA test coverage utility in IDEA to generate coverage reports.

I cannot determine why the constructor line of my Scala case class is only showing partial (yellow) coverage. I have looked in the EMMA FAQs and researched the matter online with no success. Does anyone have any idea how I can reach 100% coverage on a case class?

Solution

  • case class A(a: Any) generate a number of methods for you, among them:

    1. A#equals
    2. A#canEqual
    3. A#hashCode
    4. A#toString
    5. A#productPrefix
    6. A#productElement
    7. A#productArity
    8. A#productIterator
    9. A#copy
    10. A.unapply
    11. A.apply

    Most of these will be reported in the bytecode at the same line number as the class definition.

    You could write a reflective utility to call all of these methods in each unit test for your case classes, patch the code coverage tool to ignore that line, or just put up with it.