anchor.diff:      expect(previewInfo.applyTo(code), 'f(a, b) => (a = b)..c;');
     }
   
  -  void test_removeAs_in_cascade_target_parens_needed_throw() async {
  +  Future<void> test_removeAs_in_cascade_target_parens_needed_throw() async {
       await analyze('f(a) => ((throw a) as dynamic)..b;');
       var throw_ = findNode.throw_('throw a');
       var cast = throw_.parent.parent;
  
positive.code:     expect(previewInfo.applyTo(code), 'f(a) => a..b..c;');
    }
  
    void test_removeAs_in_cascade_target_no_parens_needed_conditional() async {
      // TODO(paulberry): would it be better to keep the parens in this case for
      // clarity, even though they're not needed?
      await analyze('f(a, b, c) => ((a ? b : c) as dynamic)..d;');
  
negative.code: 
  @reflectiveTest
  class FixAggregatorTest extends FixAggregatorTestBase {
    Future<void> test_adjacentFixes() async {
      await analyze('f(a, b) => a + b;');
      var aRef = findNode.simple('a +');
      var bRef = findNode.simple('b;');
  