Examples with DecisionState org.antlr.v4.runtime.atn.DecisionState used on opensource projects

Example 11 with DecisionState

use of org.antlr.v4.runtime.atn.DecisionState in project antlr4 by antlr.

the class BasePythonTest method checkRuleDFA.

List<ANTLRMessage> checkRuleDFA(String gtext, int decision, String expecting) throws Exception {
    ErrorQueue equeue = new ErrorQueue();
    Grammar g = new Grammar(gtext, equeue);
    ATN atn = createATN(g, false);
    DecisionState blk = atn.decisionToState.get(decision);
    checkRuleDFA(g, blk, expecting);
    return equeue.all;
}

Example 12 with DecisionState

use of org.antlr.v4.runtime.atn.DecisionState in project antlr4 by antlr.

the class ATNOptimizer method optimizeSets.

private static void optimizeSets(Grammar g, ATN atn) {
    if (g.isParser()) {
        // parser codegen doesn't currently support SetTransition
        return;
    }
    int removedStates = 0;
    List<DecisionState> decisions = atn.decisionToState;
    for (DecisionState decision : decisions) {
        if (decision.ruleIndex >= 0) {
            Rule rule = g.getRule(decision.ruleIndex);
            if (Character.isLowerCase(rule.name.charAt(0))) {
                // parser codegen doesn't currently support SetTransition
                continue;
            }
        }
        IntervalSet setTransitions = new IntervalSet();
        for (int i = 0; i < decision.getNumberOfTransitions(); i++) {
            Transition epsTransition = decision.transition(i);
            if (!(epsTransition instanceof EpsilonTransition)) {
                continue;
            }
            if (epsTransition.target.getNumberOfTransitions() != 1) {
                continue;
            }
            Transition transition = epsTransition.target.transition(0);
            if (!(transition.target instanceof BlockEndState)) {
                continue;
            }
            if (transition instanceof NotSetTransition) {
                // TODO: not yet implemented
                continue;
            }
            if (transition instanceof AtomTransition || transition instanceof RangeTransition || transition instanceof SetTransition) {
                setTransitions.add(i);
            }
        }
        // due to min alt resolution policies, can only collapse sequential alts
        for (int i = setTransitions.getIntervals().size() - 1; i >= 0; i--) {
            Interval interval = setTransitions.getIntervals().get(i);
            if (interval.length() <= 1) {
                continue;
            }
            ATNState blockEndState = decision.transition(interval.a).target.transition(0).target;
            IntervalSet matchSet = new IntervalSet();
            for (int j = interval.a; j <= interval.b; j++) {
                Transition matchTransition = decision.transition(j).target.transition(0);
                if (matchTransition instanceof NotSetTransition) {
                    throw new UnsupportedOperationException("Not yet implemented.");
                }
                IntervalSet set = matchTransition.label();
                List<Interval> intervals = set.getIntervals();
                int n = intervals.size();
                for (int k = 0; k < n; k++) {
                    Interval setInterval = intervals.get(k);
                    int a = setInterval.a;
                    int b = setInterval.b;
                    if (a != -1 && b != -1) {
                        for (int v = a; v <= b; v++) {
                            if (matchSet.contains(v)) {
                                // TODO: Token is missing (i.e. position in source will not be displayed).
                                g.tool.errMgr.grammarError(ErrorType.CHARACTERS_COLLISION_IN_SET, g.fileName, null, CharSupport.getANTLRCharLiteralForChar(v), CharSupport.getIntervalSetEscapedString(matchSet));
                                break;
                            }
                        }
                    }
                }
                matchSet.addAll(set);
            }
            Transition newTransition;
            if (matchSet.getIntervals().size() == 1) {
                if (matchSet.size() == 1) {
                    newTransition = CodePointTransitions.createWithCodePoint(blockEndState, matchSet.getMinElement());
                } else {
                    Interval matchInterval = matchSet.getIntervals().get(0);
                    newTransition = CodePointTransitions.createWithCodePointRange(blockEndState, matchInterval.a, matchInterval.b);
                }
            } else {
                newTransition = new SetTransition(blockEndState, matchSet);
            }
            decision.transition(interval.a).target.setTransition(0, newTransition);
            for (int j = interval.a + 1; j <= interval.b; j++) {
                Transition removed = decision.removeTransition(interval.a + 1);
                atn.removeState(removed.target);
                removedStates++;
            }
        }
    }
//		System.out.println("ATN optimizer removed " + removedStates + " states by collapsing sets.");
}

Example 13 with DecisionState

use of org.antlr.v4.runtime.atn.DecisionState in project antlr4 by antlr.

the class BaseJavaTest method checkRuleDFA.

List<ANTLRMessage> checkRuleDFA(String gtext, int decision, String expecting) throws Exception {
    ErrorQueue equeue = new ErrorQueue();
    Grammar g = new Grammar(gtext, equeue);
    ATN atn = createATN(g, false);
    DecisionState blk = atn.decisionToState.get(decision);
    checkRuleDFA(g, blk, expecting);
    return equeue.all;
}

Example 14 with DecisionState

use of org.antlr.v4.runtime.atn.DecisionState in project antlr4 by antlr.

the class BaseCppTest method checkRuleDFA.

List<ANTLRMessage> checkRuleDFA(String gtext, int decision, String expecting) throws Exception {
    ErrorQueue equeue = new ErrorQueue();
    Grammar g = new Grammar(gtext, equeue);
    ATN atn = createATN(g, false);
    DecisionState blk = atn.decisionToState.get(decision);
    checkRuleDFA(g, blk, expecting);
    return equeue.all;
}

Example 15 with DecisionState

use of org.antlr.v4.runtime.atn.DecisionState in project antlr4 by antlr.

the class TestAmbigParseTrees method testInterpAtSpecificAlt.

void testInterpAtSpecificAlt(LexerGrammar lg, Grammar g, String startRule, int startAlt, String input, String expectedParseTree) {
    LexerInterpreter lexEngine = lg.createLexerInterpreter(new ANTLRInputStream(input));
    CommonTokenStream tokens = new CommonTokenStream(lexEngine);
    ParserInterpreter parser = g.createGrammarParserInterpreter(tokens);
    RuleStartState ruleStartState = g.atn.ruleToStartState[g.getRule(startRule).index];
    Transition tr = ruleStartState.transition(0);
    ATNState t2 = tr.target;
    if (!(t2 instanceof BasicBlockStartState)) {
        throw new IllegalArgumentException("rule has no decision: " + startRule);
    }
    parser.addDecisionOverride(((DecisionState) t2).decision, 0, startAlt);
    ParseTree t = parser.parse(g.rules.get(startRule).index);
    InterpreterTreeTextProvider nodeTextProvider = new InterpreterTreeTextProvider(g.getRuleNames());
    assertEquals(expectedParseTree, Trees.toStringTree(t, nodeTextProvider));
}