1/*
2 * [The "BSD licence"]
3 * Copyright (c) 2005-2008 Terence Parr
4 * All rights reserved.
5 *
6 * Conversion to C#:
7 * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 *    derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33namespace Antlr.Runtime.Tree
34{
35
36    /** <summary>A node representing erroneous token range in token stream</summary> */
37    [System.Serializable]
38    public class CommonErrorNode : CommonTree
39    {
40        public IIntStream input;
41        public IToken start;
42        public IToken stop;
43        public RecognitionException trappedException;
44
45        public CommonErrorNode( ITokenStream input, IToken start, IToken stop,
46                               RecognitionException e )
47        {
48            //System.out.println("start: "+start+", stop: "+stop);
49            if ( stop == null ||
50                 ( stop.TokenIndex < start.TokenIndex &&
51                  stop.Type != TokenTypes.EndOfFile ) )
52            {
53                // sometimes resync does not consume a token (when LT(1) is
54                // in follow set.  So, stop will be 1 to left to start. adjust.
55                // Also handle case where start is the first token and no token
56                // is consumed during recovery; LT(-1) will return null.
57                stop = start;
58            }
59            this.input = input;
60            this.start = start;
61            this.stop = stop;
62            this.trappedException = e;
63        }
64
65        #region Properties
66        public override bool IsNil
67        {
68            get
69            {
70                return false;
71            }
72        }
73        public override string Text
74        {
75            get
76            {
77                string badText = null;
78                if ( start is IToken )
79                {
80                    int i = ( (IToken)start ).TokenIndex;
81                    int j = ( (IToken)stop ).TokenIndex;
82                    if ( ( (IToken)stop ).Type == TokenTypes.EndOfFile )
83                    {
84                        j = ( (ITokenStream)input ).Count;
85                    }
86                    badText = ( (ITokenStream)input ).ToString( i, j );
87                }
88                else if ( start is ITree )
89                {
90                    badText = ( (ITreeNodeStream)input ).ToString( start, stop );
91                }
92                else
93                {
94                    // people should subclass if they alter the tree type so this
95                    // next one is for sure correct.
96                    badText = "<unknown>";
97                }
98                return badText;
99            }
100            set
101            {
102            }
103        }
104        public override int Type
105        {
106            get
107            {
108                return TokenTypes.Invalid;
109            }
110            set
111            {
112            }
113        }
114        #endregion
115
116        public override string ToString()
117        {
118            if ( trappedException is MissingTokenException )
119            {
120                return "<missing type: " +
121                       ( (MissingTokenException)trappedException ).MissingType +
122                       ">";
123            }
124            else if ( trappedException is UnwantedTokenException )
125            {
126                return "<extraneous: " +
127                       ( (UnwantedTokenException)trappedException ).UnexpectedToken +
128                       ", resync=" + Text + ">";
129            }
130            else if ( trappedException is MismatchedTokenException )
131            {
132                return "<mismatched token: " + trappedException.Token + ", resync=" + Text + ">";
133            }
134            else if ( trappedException is NoViableAltException )
135            {
136                return "<unexpected: " + trappedException.Token +
137                       ", resync=" + Text + ">";
138            }
139            return "<error: " + Text + ">";
140        }
141    }
142}
143