1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/*
* [The "BSD license"]
* Copyright (c) 2010 Terence Parr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.antlr.tool;
import org.antlr.Tool;
import org.antlr.analysis.Label;
import org.antlr.analysis.NFAState;
import org.antlr.analysis.RuleClosureTransition;
import org.antlr.analysis.Transition;
import org.antlr.misc.IntervalSet;
import org.antlr.misc.Utils;
import java.io.BufferedReader;
import java.io.FileReader;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.Stack;
/** Generate a random phrase given a grammar.
* Usage:
* java org.antlr.tool.RandomPhrase grammarFile.g startRule [seed]
*
* For example:
* java org.antlr.tool.RandomPhrase simple.g program 342
*
* The seed acts like a unique identifier so you can get the same random
* phrase back during unit testing, for example.
*
* If you do not specify a seed then the current time in milliseconds is used
* guaranteeing that you'll never see that seed again.
*
* NOTE: this does not work well for large grammars...it tends to recurse
* too much and build really long strings. I need throttle control; later.
*/
public class RandomPhrase {
public static final boolean debug = false;
protected static Random random;
/** an experimental method to generate random phrases for a given
* grammar given a start rule. Return a list of token types.
*/
protected static void randomPhrase(Grammar g, List<Integer> tokenTypes, String startRule) {
NFAState state = g.getRuleStartState(startRule);
NFAState stopState = g.getRuleStopState(startRule);
Stack ruleInvocationStack = new Stack();
while ( true ) {
if ( state==stopState && ruleInvocationStack.size()==0 ) {
break;
}
if ( debug ) System.out.println("state "+state);
if ( state.getNumberOfTransitions()==0 ) {
if ( debug ) System.out.println("dangling state: "+state);
return;
}
// end of rule node
if ( state.isAcceptState() ) {
NFAState invokingState = (NFAState)ruleInvocationStack.pop();
if ( debug ) System.out.println("pop invoking state "+invokingState);
//System.out.println("leave "+state.enclosingRule.name);
RuleClosureTransition invokingTransition =
(RuleClosureTransition)invokingState.transition[0];
// move to node after state that invoked this rule
state = invokingTransition.followState;
continue;
}
if ( state.getNumberOfTransitions()==1 ) {
// no branching, just take this path
Transition t0 = state.transition[0];
if ( t0 instanceof RuleClosureTransition ) {
ruleInvocationStack.push(state);
if ( debug ) System.out.println("push state "+state);
//System.out.println("call "+((RuleClosureTransition)t0).rule.name);
//System.out.println("stack depth="+ruleInvocationStack.size());
}
else if ( t0.label.isSet() || t0.label.isAtom() ) {
tokenTypes.add( getTokenType(t0.label) );
}
state = (NFAState)t0.target;
continue;
}
int decisionNumber = state.getDecisionNumber();
if ( decisionNumber==0 ) {
System.out.println("weird: no decision number but a choice node");
continue;
}
// decision point, pick ith alternative randomly
int n = g.getNumberOfAltsForDecisionNFA(state);
int randomAlt = random.nextInt(n) + 1;
if ( debug ) System.out.println("randomAlt="+randomAlt);
NFAState altStartState =
g.getNFAStateForAltOfDecision(state, randomAlt);
Transition t = altStartState.transition[0];
state = (NFAState)t.target;
}
}
protected static Integer getTokenType(Label label) {
if ( label.isSet() ) {
// pick random element of set
IntervalSet typeSet = (IntervalSet)label.getSet();
int randomIndex = random.nextInt(typeSet.size());
return typeSet.get(randomIndex);
}
else {
return Utils.integer(label.getAtom());
}
//System.out.println(t0.label.toString(g));
}
/** Used to generate random strings */
public static void main(String[] args) {
if ( args.length < 2 ) {
System.err.println("usage: java org.antlr.tool.RandomPhrase grammarfile startrule");
return;
}
String grammarFileName = args[0];
String startRule = args[1];
long seed = System.currentTimeMillis(); // use random seed unless spec.
if ( args.length==3 ) {
String seedStr = args[2];
seed = Long.parseLong(seedStr);
}
try {
random = new Random(seed);
CompositeGrammar composite = new CompositeGrammar();
Tool tool = new Tool();
Grammar parser = new Grammar(tool, grammarFileName, composite);
composite.setDelegationRoot(parser);
FileReader fr = new FileReader(grammarFileName);
BufferedReader br = new BufferedReader(fr);
parser.parseAndBuildAST(br);
br.close();
parser.composite.assignTokenTypes();
parser.composite.defineGrammarSymbols();
parser.composite.createNFAs();
List leftRecursiveRules = parser.checkAllRulesForLeftRecursion();
if ( leftRecursiveRules.size()>0 ) {
return;
}
if ( parser.getRule(startRule)==null ) {
System.out.println("undefined start rule "+startRule);
return;
}
String lexerGrammarText = parser.getLexerGrammar();
Grammar lexer = new Grammar(tool);
lexer.importTokenVocabulary(parser);
lexer.fileName = grammarFileName;
if ( lexerGrammarText!=null ) {
lexer.setGrammarContent(lexerGrammarText);
}
else {
System.err.println("no lexer grammar found in "+grammarFileName);
}
lexer.buildNFA();
leftRecursiveRules = lexer.checkAllRulesForLeftRecursion();
if ( leftRecursiveRules.size()>0 ) {
return;
}
//System.out.println("lexer:\n"+lexer);
List<Integer> tokenTypes = new ArrayList<Integer>(100);
randomPhrase(parser, tokenTypes, startRule);
System.out.println("token types="+tokenTypes);
for (int i = 0; i < tokenTypes.size(); i++) {
Integer ttypeI = (Integer) tokenTypes.get(i);
int ttype = ttypeI.intValue();
String ttypeDisplayName = parser.getTokenDisplayName(ttype);
if ( Character.isUpperCase(ttypeDisplayName.charAt(0)) ) {
List<Integer> charsInToken = new ArrayList<Integer>(10);
randomPhrase(lexer, charsInToken, ttypeDisplayName);
System.out.print(" ");
for (int j = 0; j < charsInToken.size(); j++) {
java.lang.Integer cI = (java.lang.Integer) charsInToken.get(j);
System.out.print((char)cI.intValue());
}
}
else { // it's a literal
String literal =
ttypeDisplayName.substring(1,ttypeDisplayName.length()-1);
System.out.print(" "+literal);
}
}
System.out.println();
}
catch (Error er) {
System.err.println("Error walking "+grammarFileName+" rule "+startRule+" seed "+seed);
er.printStackTrace(System.err);
}
catch (Exception e) {
System.err.println("Exception walking "+grammarFileName+" rule "+startRule+" seed "+seed);
e.printStackTrace(System.err);
}
}
}
|
