Improve repoorting of NoSuchMethod:

corelib/src/exceptions.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // Exceptions are thrown either by the VM or from Dart code.
 
 /**
  * Interface implemented by all core library exceptions.
  */
 interface Exception default ExceptionImplementation {
@@ skipping 20 matching lines @@
 }
 
 
 /**
  * Exception thrown because of non-existing receiver's method.
  */
 class NoSuchMethodException implements Exception {
   const NoSuchMethodException(Object this._receiver,
                               String this._functionName,
                               List this._arguments,
-                              [String this._extraMessage = ""]);
+                              [List this._existingArgumentNames = null]);
 
   String toString() {
     StringBuffer sb = new StringBuffer();
     for (int i = 0; i < _arguments.length; i++) {
       if (i > 0) {
         sb.add(", ");
       }
       sb.add(_arguments[i]);
     }
-    sb.add("]");
-    var x = _extraMessage;
-    return "NoSuchMethodException - receiver: '$_receiver' " +
-           "function name: '$_functionName' arguments: [$sb]$x";
+    if (_existingArgumentNames === null) {
+      return "NoSuchMethodException : method not found: '$_functionName'\n" +
+          "Receiver: $_receiver\n" + "Arguments: [$sb]";
+    } else {
+      String actualParameters = sb.toString();
+      sb = new StringBuffer();
+      for (int i = 0; i < _existingArgumentNames.length; i++) {
+        if (i > 0) {
+          sb.add(", ");
+        }
+        sb.add(_existingArgumentNames[i]);
+      }
+      String formalParameters = sb.toString();
+      return "NoSuchMethodException: incorrect number of arguments passed to " +
+          "method named '$_functionName'\nReceiver: $_receiver\n" +
+          "Tried calling: $_functionName($actualParameters)\n" +
+          "Found: $_functionName($formalParameters)";
+    }
   }
 
   final Object _receiver;
   final String _functionName;
   final List _arguments;
-  final String _extraMessage;
+  final List _existingArgumentNames;
 }
 
 
 class ClosureArgumentMismatchException implements Exception {
   const ClosureArgumentMismatchException();
   String toString() => "Closure argument mismatch";
 }
 
 
 class ObjectNotClosureException implements Exception {
@@ skipping 70 matching lines @@
   String toString() => "IllegalJSRegExpException: '$_pattern' '$_errmsg'";
   final String _pattern;
   final String _errmsg;
 }
 
 
 class IntegerDivisionByZeroException implements Exception {
   const IntegerDivisionByZeroException();
   String toString() => "IntegerDivisionByZeroException";
 }