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

Example 51 with DFA

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

the class TestATNParserPrediction method testRecursiveLeftPrefix.

@Test
public void testRecursiveLeftPrefix() throws Exception {
    LexerGrammar lg = new LexerGrammar("lexer grammar L;\n" + "A : 'a' ;\n" + "B : 'b' ;\n" + "C : 'c' ;\n" + "LP : '(' ;\n" + "RP : ')' ;\n" + "INT : '0'..'9'+ ;\n");
    Grammar g = new Grammar("parser grammar T;\n" + "tokens {A,B,C,LP,RP,INT}\n" + "a : e B | e C ;\n" + "e : LP e RP\n" + "  | INT\n" + "  ;");
    int decision = 0;
    checkPredictedAlt(lg, g, decision, "34b", 1);
    checkPredictedAlt(lg, g, decision, "34c", 2);
    checkPredictedAlt(lg, g, decision, "((34))b", 1);
    checkPredictedAlt(lg, g, decision, "((34))c", 2);
    // After matching these inputs for decision, what is DFA after each prediction?
    String[] inputs = { "34b", "34c", "((34))b", "((34))c" };
    String[] dfa = { "s0-INT->s1\n" + "s1-'b'->:s2=>1\n", "s0-INT->s1\n" + "s1-'b'->:s2=>1\n" + "s1-'c'->:s3=>2\n", "s0-'('->s4\n" + "s0-INT->s1\n" + "s1-'b'->:s2=>1\n" + "s1-'c'->:s3=>2\n" + "s4-'('->s5\n" + "s5-INT->s6\n" + "s6-')'->s7\n" + "s7-')'->s1\n", "s0-'('->s4\n" + "s0-INT->s1\n" + "s1-'b'->:s2=>1\n" + "s1-'c'->:s3=>2\n" + "s4-'('->s5\n" + "s5-INT->s6\n" + "s6-')'->s7\n" + "s7-')'->s1\n" };
    checkDFAConstruction(lg, g, decision, inputs, dfa);
}

Example 52 with DFA

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

the class TestATNParserPrediction method testRuleRefxory.

@Test
public void testRuleRefxory() throws Exception {
    LexerGrammar lg = new LexerGrammar("lexer grammar L;\n" + "A : 'a' ;\n" + "B : 'b' ;\n" + "C : 'c' ;\n");
    Grammar g = new Grammar("parser grammar T;\n" + "a : x | y ;\n" + "x : A ;\n" + "y : B ;\n");
    int decision = 0;
    checkPredictedAlt(lg, g, decision, "a", 1);
    checkPredictedAlt(lg, g, decision, "b", 2);
    // After matching these inputs for decision, what is DFA after each prediction?
    String[] inputs = { "a", "b", "a" };
    String[] dfa = { "s0-'a'->:s1=>1\n", "s0-'a'->:s1=>1\n" + "s0-'b'->:s2=>2\n", // don't change after it works
    "s0-'a'->:s1=>1\n" + "s0-'b'->:s2=>2\n" };
    checkDFAConstruction(lg, g, decision, inputs, dfa);
}

Example 53 with DFA

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

the class TestATNParserPrediction method testOptionalRuleChasesGlobalFollow.

@Test
public void testOptionalRuleChasesGlobalFollow() throws Exception {
    LexerGrammar lg = new LexerGrammar("lexer grammar L;\n" + "A : 'a' ;\n" + "B : 'b' ;\n" + "C : 'c' ;\n");
    Grammar g = new Grammar("parser grammar T;\n" + "tokens {A,B,C}\n" + "a : x B ;\n" + "b : x C ;\n" + "x : A | ;\n");
    int decision = 0;
    checkPredictedAlt(lg, g, decision, "a", 1);
    checkPredictedAlt(lg, g, decision, "b", 2);
    checkPredictedAlt(lg, g, decision, "c", 2);
    // After matching these inputs for decision, what is DFA after each prediction?
    String[] inputs = { "a", "b", "c", "c" };
    String[] dfa = { "s0-'a'->:s1=>1\n", "s0-'a'->:s1=>1\n" + "s0-'b'->:s2=>2\n", "s0-'a'->:s1=>1\n" + "s0-'b'->:s2=>2\n" + "s0-'c'->:s3=>2\n", "s0-'a'->:s1=>1\n" + "s0-'b'->:s2=>2\n" + "s0-'c'->:s3=>2\n" };
    checkDFAConstruction(lg, g, decision, inputs, dfa);
}

Example 54 with DFA

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

the class TestATNParserPrediction method testEmptyInput.

@Test
public void testEmptyInput() throws Exception {
    LexerGrammar lg = new LexerGrammar("lexer grammar L;\n" + "A : 'a' ;\n" + "B : 'b' ;\n" + "C : 'c' ;\n");
    Grammar g = new Grammar("parser grammar T;\n" + "a : A | ;");
    int decision = 0;
    checkPredictedAlt(lg, g, decision, "a", 1);
    checkPredictedAlt(lg, g, decision, "", 2);
    // After matching these inputs for decision, what is DFA after each prediction?
    String[] inputs = { "a", "" };
    String[] dfa = { "s0-'a'->:s1=>1\n", "s0-EOF->:s2=>2\n" + "s0-'a'->:s1=>1\n" };
    checkDFAConstruction(lg, g, decision, inputs, dfa);
}

Example 55 with DFA

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

the class TestATNParserPrediction method testPEGAchillesHeel.

@Test
public void testPEGAchillesHeel() throws Exception {
    LexerGrammar lg = new LexerGrammar("lexer grammar L;\n" + "A : 'a' ;\n" + "B : 'b' ;\n" + "C : 'c' ;\n");
    Grammar g = new Grammar("parser grammar T;\n" + "a : A | A B ;");
    checkPredictedAlt(lg, g, 0, "a", 1);
    checkPredictedAlt(lg, g, 0, "ab", 2);
    checkPredictedAlt(lg, g, 0, "abc", 2);
    String[] inputs = { "a", "ab", "abc" };
    String[] dfa = { "s0-'a'->s1\n" + "s1-EOF->:s2=>1\n", "s0-'a'->s1\n" + "s1-EOF->:s2=>1\n" + "s1-'b'->:s3=>2\n", "s0-'a'->s1\n" + "s1-EOF->:s2=>1\n" + "s1-'b'->:s3=>2\n" };
    checkDFAConstruction(lg, g, 0, inputs, dfa);
}