listTests = testGroup "List Tests"
  [ testCase "empty lists are recognized" testEmptyList
  , testCase "lists with elements are recognized" testFilledList ]
listTests = testGroup "List Tests"
  [ testCase "empty lists are recognized" testEmptyList
  , testCase "lists with elements are recognized" testFilledList ]
listTests = testGroup "List Tests"
  [ testCase "empty lists are recognized" testEmptyList
  , testCase "lists with elements are recognized" testFilledList ]