frog: detect when getter/setter has incorrect number of arguments.

frog/minfrog

 #!/usr/bin/env node
 //  ********** Library dart:core **************
 //  ********** Natives dart:core **************
 /**
  * Generates a dynamic call stub for a function.
  * Our goal is to create a stub method like this on-the-fly:
  *   function($0, $1, capture) { return this($0, $1, true, capture); }
  *
  * This stub then replaces the dynamic one on Function, with one that is
  * specialized for that particular function, taking into account its default
@@ skipping 5005 matching lines @@
     var c = parentMember;
     parent = c.baseMember;
   }
   else {
     parent = parentMember;
   }
   if (this.getter == null) this.getter = parent.getter;
   if (this.setter == null) this.setter = parent.setter;
 }
 PropertyMember.prototype.resolve = function() {
-  if (this.getter != null) this.getter.resolve();
-  if (this.setter != null) this.setter.resolve();
+  if (this.getter != null) {
+    this.getter.resolve();
+    if (this.getter.parameters.length != 0) {
+      $globals.world.error('getter methods should take no arguments', this.getter.definition.span);
+    }
+  }
+  if (this.setter != null) {
+    this.setter.resolve();
+    if (this.setter.parameters.length != 1) {
+      $globals.world.error('setter methods should take a single argument', this.setter.definition.span);
+    }
+  }
   this.get$library()._addMember(this);
 }
 PropertyMember.prototype._get$3 = function($0, $1, $2) {
   return this._get($0, $1, $2, false);
 };
 PropertyMember.prototype._get$3$isDynamic = PropertyMember.prototype._get;
 PropertyMember.prototype._get$4 = PropertyMember.prototype._get;
 PropertyMember.prototype._set$4 = function($0, $1, $2, $3) {
   return this._set($0, $1, $2, $3, false);
 };
@@ skipping 8148 matching lines @@
   $globals._MAGENTA_COLOR = '\u001b[35m';
   $globals._NO_COLOR = '\u001b[0m';
   $globals._RED_COLOR = '\u001b[31m';
 }
 var const$0 = new NoMoreElementsException()/*const NoMoreElementsException()*/;
 var const$2 = new EmptyQueueException()/*const EmptyQueueException()*/;
 var const$3 = new _DeletedKeySentinel()/*const _DeletedKeySentinel()*/;
 var $globals = {};
 $static_init();
 main();