/*
* [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.analysis.DFAState;
import org.antlr.analysis.DecisionProbe;
import org.antlr.analysis.NFAState;
import org.antlr.misc.Utils;
import org.stringtemplate.v4.ST;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
/** Reports a potential parsing issue with a decision; the decision is
* nondeterministic in some way.
*/
public class GrammarNonDeterminismMessage extends Message {
public DecisionProbe probe;
public DFAState problemState;
public GrammarNonDeterminismMessage(DecisionProbe probe,
DFAState problemState)
{
super(ErrorManager.MSG_GRAMMAR_NONDETERMINISM);
this.probe = probe;
this.problemState = problemState;
// flip msg ID if alts are actually token refs in Tokens rule
if ( probe.dfa.isTokensRuleDecision() ) {
setMessageID(ErrorManager.MSG_TOKEN_NONDETERMINISM);
}
}
public String toString() {
GrammarAST decisionASTNode = probe.dfa.getDecisionASTNode();
line = decisionASTNode.getLine();
column = decisionASTNode.getCharPositionInLine();
String fileName = probe.dfa.nfa.grammar.getFileName();
if ( fileName!=null ) {
file = fileName;
}
ST st = getMessageTemplate();
// Now fill template with information about problemState
List labels = probe.getSampleNonDeterministicInputSequence(problemState);
String input = probe.getInputSequenceDisplay(labels);
st.add("input", input);
if ( probe.dfa.isTokensRuleDecision() ) {
Set disabledAlts = probe.getDisabledAlternatives(problemState);
for (Iterator it = disabledAlts.iterator(); it.hasNext();) {
Integer altI = (Integer) it.next();
String tokenName =
probe.getTokenNameForTokensRuleAlt(altI.intValue());
// reset the line/col to the token definition (pick last one)
NFAState ruleStart =
probe.dfa.nfa.grammar.getRuleStartState(tokenName);
line = ruleStart.associatedASTNode.getLine();
column = ruleStart.associatedASTNode.getCharPositionInLine();
st.add("disabled", tokenName);
}
}
else {
st.add("disabled", probe.getDisabledAlternatives(problemState));
}
List nondetAlts = probe.getNonDeterministicAltsForState(problemState);
NFAState nfaStart = probe.dfa.getNFADecisionStartState();
// all state paths have to begin with same NFA state
int firstAlt = 0;
if ( nondetAlts!=null ) {
for (Iterator iter = nondetAlts.iterator(); iter.hasNext();) {
Integer displayAltI = (Integer) iter.next();
if ( DecisionProbe.verbose ) {
int tracePathAlt =
nfaStart.translateDisplayAltToWalkAlt(displayAltI.intValue());
if ( firstAlt == 0 ) {
firstAlt = tracePathAlt;
}
List path =
probe.getNFAPathStatesForAlt(firstAlt,
tracePathAlt,
labels);
st.addAggr("paths.{alt, states}", displayAltI, path);
}
else {
if ( probe.dfa.isTokensRuleDecision() ) {
// alts are token rules, convert to the names instead of numbers
String tokenName =
probe.getTokenNameForTokensRuleAlt(displayAltI.intValue());
st.add("conflictingTokens", tokenName);
}
else {
st.add("conflictingAlts", displayAltI);
}
}
}
}
st.add("hasPredicateBlockedByAction", problemState.dfa.hasPredicateBlockedByAction);
return super.toString(st);
}
}