testNullOpExpr :: Test
testNullOpExpr = TestList
  [ testEq "Parse mutex expression" (NullOpExpr Mut) "mutex()"
  , testEq "Parse yield expression" (NullOpExpr Yield) "yield()"
  ]
testNullOpExpr :: Test
testNullOpExpr = TestList
  [ testEq "Parse mutex expression" (NullOpExpr Mut) "mutex()"
  , testEq "Parse yield expression" (NullOpExpr Yield) "yield()"
  ]
testNullOpExpr = TestList
  [ testEq "Parse mutex expression" (NullOpExpr Mut) "mutex()"
  , testEq "Parse yield expression" (NullOpExpr Yield) "yield()"
  ]