anchor.diff:    }
   
     /**
  -   * Return `true` if the given AST nodes have the same structure. As a side-effect, if the
  -   * nodes do have the same structure, any resolution data from the first node will be copied to the
  -   * second node.
  -   *
  -   * @param fromNode the node from which resolution information will be copied
  -   * @param toNode the node to which resolution information will be copied
  -   * @return `true` if the given AST nodes have the same structure
  +   * Return `true` if the [fromNode] and [toNode] have the same structure. As a
  +   * side-effect, if the nodes do have the same structure, any resolution data
  +   * from the first node will be copied to the second node.
      */
     bool _isEqualNodes(AstNode fromNode, AstNode toNode) {
       if (fromNode == null) {
  
positive.code:   }
  
    /**
     * Parse the name of a constructor.
     *
     * <pre>
     * constructorName:
     *     type ('.' identifier)?
     * </pre>
     *
     * @return the constructor name that was parsed
     */
    ConstructorName parseConstructorName() {
      TypeName type = parseTypeName();
  
negative.code:   }
  
    /**
     * Validate that the given set of [modifiers] is appropriate for a top-level
     * function.
     */
    void _validateModifiersForTopLevelFunction(Modifiers modifiers) {
      _validateModifiersForTopLevelDeclaration(modifiers);
  