anchor.diff:  
   /** Class with noSuchMethod that returns the mirror */
   class N {
  -  noSuchMethod(InvocationMirror m) => m;
  +  // Storage for the last argument to noSuchMethod.
  +  // Needed for setters, which don't evaluate to the return value.
  +  var last;
  +  noSuchMethod(InvocationMirror m) => last = m;
   
     get wut => this;
   
  
positive.code: 
    // Missing property/method access.
    testInvocationMirror(n.bar, 'bar');
    testInvocationMirror(n.bar = 42, 'bar=', [42]);
    testInvocationMirror(n.bar(), 'bar', [], {});
    testInvocationMirror(n.bar(42), 'bar', [42], {});
    testInvocationMirror(n.bar(x: 42), 'bar', [], {"x": 42});
  
negative.code:   // Missing operator access.
    testInvocationMirror(n + 4, '+', [4], {});
    testInvocationMirror(n - 4, '-', [4], {});
    testInvocationMirror(-n, '-', [], {});
    testInvocationMirror(n[42], '[]', [42], {});
    testInvocationMirror((n..[37] = 42).last, '[]=', [37, 42], {});
  
    // Calling as function when it's not.
    testInvocationMirror(n(), 'call', [], {});
  