Examples with DFA org.antlr.v4.runtime.dfa.DFA used on opensource projects

Example 21 with DFA

use of org.antlr.v4.runtime.dfa.DFA in project antlr4 by tunnelvisionlabs.

the class BaseTest method checkRuleDFA.

void checkRuleDFA(Grammar g, DecisionState blk, String expecting) throws Exception {
    DFA dfa = createDFA(g, blk);
    String result = null;
    if (dfa != null)
        result = dfa.toString();
    assertEquals(expecting, result);
}

Example 22 with DFA

use of org.antlr.v4.runtime.dfa.DFA in project antlr4 by tunnelvisionlabs.

the class BaseTest method getTypesFromString.

// public void minimizeDFA(DFA dfa) {
// DFAMinimizer dmin = new DFAMinimizer(dfa);
// dfa.minimized = dmin.minimize();
// }
IntegerList getTypesFromString(Grammar g, String expecting) {
    IntegerList expectingTokenTypes = new IntegerList();
    if (expecting != null && !expecting.trim().isEmpty()) {
        for (String tname : expecting.replace(" ", "").split(",")) {
            int ttype = g.getTokenType(tname);
            expectingTokenTypes.add(ttype);
        }
    }
    return expectingTokenTypes;
}

Example 23 with DFA

use of org.antlr.v4.runtime.dfa.DFA in project antlr4 by tunnelvisionlabs.

the class LexerATNFactory method stringLiteral.

/**
 * For a lexer, a string is a sequence of char to match.  That is,
 *  "fog" is treated as 'f' 'o' 'g' not as a single transition in
 *  the DFA.  Machine== o-'f'->o-'o'->o-'g'->o and has n+1 states
 *  for n characters.
 */
@Override
public Handle stringLiteral(TerminalAST stringLiteralAST) {
    String chars = stringLiteralAST.getText();
    ATNState left = newState(stringLiteralAST);
    ATNState right;
    String s = CharSupport.getStringFromGrammarStringLiteral(chars);
    if (s == null) {
        // the lexer will already have given an error
        return new Handle(left, left);
    }
    int n = s.length();
    ATNState prev = left;
    right = null;
    for (int i = 0; i < n; ) {
        right = newState(stringLiteralAST);
        int codePoint = s.codePointAt(i);
        prev.addTransition(CodePointTransitions.createWithCodePoint(right, codePoint));
        prev = right;
        i += Character.charCount(codePoint);
    }
    stringLiteralAST.atnState = left;
    return new Handle(left, right);
}

Example 24 with DFA

use of org.antlr.v4.runtime.dfa.DFA in project antlr4 by tunnelvisionlabs.

the class DOTGenerator method getDOT.

public String getDOT(DFA dfa, boolean isLexer) {
    if (dfa.s0.get() == null)
        return null;
    ST dot = stlib.getInstanceOf("dfa");
    dot.add("name", "DFA" + dfa.decision);
    dot.add("startState", dfa.s0.get().stateNumber);
    // dot.add("useBox", Tool.internalOption_ShowATNConfigsInDFA);
    dot.add("rankdir", rankdir);
    // define stop states first; seems to be a bug in DOT where doublecircle
    for (DFAState d : dfa.states.keySet()) {
        if (!d.isAcceptState())
            continue;
        ST st = stlib.getInstanceOf("stopstate");
        st.add("name", "s" + d.stateNumber);
        st.add("label", getStateLabel(d));
        dot.add("states", st);
    }
    for (DFAState d : dfa.states.keySet()) {
        if (d.isAcceptState())
            continue;
        if (d.stateNumber == Integer.MAX_VALUE)
            continue;
        ST st = stlib.getInstanceOf("state");
        st.add("name", "s" + d.stateNumber);
        st.add("label", getStateLabel(d));
        dot.add("states", st);
    }
    for (DFAState d : dfa.states.keySet()) {
        Map<Integer, DFAState> edges = d.getEdgeMap();
        for (Map.Entry<Integer, DFAState> entry : edges.entrySet()) {
            DFAState target = entry.getValue();
            if (target == null)
                continue;
            if (target.stateNumber == Integer.MAX_VALUE)
                continue;
            int ttype = entry.getKey();
            String label = String.valueOf(ttype);
            if (isLexer)
                label = "'" + getEdgeLabel(new StringBuilder().appendCodePoint(entry.getKey()).toString()) + "'";
            else if (grammar != null)
                label = grammar.getTokenDisplayName(ttype);
            ST st = stlib.getInstanceOf("edge");
            st.add("label", label);
            st.add("src", "s" + d.stateNumber);
            st.add("target", "s" + target.stateNumber);
            st.add("arrowhead", arrowhead);
            dot.add("edges", st);
        }
    }
    String output = dot.render();
    return Utils.sortLinesInString(output);
}

Example 25 with DFA

use of org.antlr.v4.runtime.dfa.DFA in project antlr4 by tunnelvisionlabs.

the class ParserATNSimulator method getStartState.

protected SimulatorState getStartState(@NotNull DFA dfa, @NotNull TokenStream input, @NotNull ParserRuleContext outerContext, boolean useContext) {
    if (!useContext) {
        if (dfa.isPrecedenceDfa()) {
            // the start state for a precedence DFA depends on the current
            // parser precedence, and is provided by a DFA method.
            DFAState state = dfa.getPrecedenceStartState(parser.getPrecedence(), false);
            if (state == null) {
                return null;
            }
            return new SimulatorState(outerContext, state, false, outerContext);
        } else {
            if (dfa.s0.get() == null) {
                return null;
            }
            return new SimulatorState(outerContext, dfa.s0.get(), false, outerContext);
        }
    }
    if (!enable_global_context_dfa) {
        return null;
    }
    ParserRuleContext remainingContext = outerContext;
    assert outerContext != null;
    DFAState s0;
    if (dfa.isPrecedenceDfa()) {
        s0 = dfa.getPrecedenceStartState(parser.getPrecedence(), true);
    } else {
        s0 = dfa.s0full.get();
    }
    while (remainingContext != null && s0 != null && s0.isContextSensitive()) {
        remainingContext = skipTailCalls(remainingContext);
        s0 = s0.getContextTarget(getReturnState(remainingContext));
        if (remainingContext.isEmpty()) {
            assert s0 == null || !s0.isContextSensitive();
        } else {
            remainingContext = remainingContext.getParent();
        }
    }
    if (s0 == null) {
        return null;
    }
    return new SimulatorState(outerContext, s0, useContext, remainingContext);
}