testchardfaconversion.java

antlr最新版本V3源代码

			"lexer grammar t;\n"+
			"SLCMT : '//' .+ '\n' ;");
		String expecting =
			".s0-'\\n'->:s1=>2\n" +
			".s0-{'\\u0000'..'\\t', '\\u000B'..'\\uFFFE'}->:s2=>1\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNonGreedyByDefaultWildcardPlusWithParens() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar t;\n"+
			"SLCMT : '//' (.)+ '\n' ;");
		String expecting =
			".s0-'\\n'->:s1=>2\n" +
			".s0-{'\\u0000'..'\\t', '\\u000B'..'\\uFFFE'}->:s2=>1\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNonWildcardNonGreedy() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar t;\n"+
			"DUH : (options {greedy=false;}:'x'|'y')* 'xy' ;");
		String expecting =
			".s0-'x'->.s1\n" +
			".s0-'y'->:s4=>2\n" +
			".s1-'x'->:s3=>1\n" +
			".s1-'y'->:s2=>3\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNonWildcardEOTMakesItWorkWithoutNonGreedyOption() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar t;\n"+
			"DUH : ('x'|'y')* 'xy' ;");
		String expecting =
			".s0-'x'->.s1\n" +
			".s0-'y'->:s3=>1\n" +
			".s1-'x'->:s3=>1\n" +
			".s1-'y'->.s2\n" +
			".s2-'x'..'y'->:s3=>1\n" +
			".s2-<EOT>->:s4=>2\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testAltConflictsWithLoopThenExit() throws Exception {
		// \" predicts alt 1, but wildcard then " can predict exit also
		Grammar g = new Grammar(
			"lexer grammar t;\n"+
			"STRING : '\"' (options {greedy=false;}: '\\\\\"' | .)* '\"' ;\n"
		);
		String expecting =
			".s0-'\"'->:s1=>3\n" +
				".s0-'\\\\'->.s2\n" +
				".s0-{'\\u0000'..'!', '#'..'[', ']'..'\\uFFFE'}->:s4=>2\n" +
				".s2-'\"'->:s3=>1\n" +
				".s2-{'\\u0000'..'!', '#'..'\\uFFFE'}->:s4=>2\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNonGreedyLoopThatNeverLoops() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar t;\n"+
			"DUH : (options {greedy=false;}:'x')+ ;"); // loop never matched
		String expecting =
			":s0=>2\n";

		ErrorQueue equeue = new ErrorQueue();
		ErrorManager.setErrorListener(equeue);

		checkDecision(g, 1, expecting, new int[] {1});

		assertEquals("unexpected number of expected problems",
				    1, equeue.size());
		Message msg = (Message)equeue.warnings.get(0);
		assertTrue("warning must be an unreachable alt",
				   msg instanceof GrammarUnreachableAltsMessage);
		GrammarUnreachableAltsMessage u = (GrammarUnreachableAltsMessage)msg;
		assertEquals("[1]", u.alts.toString());
	}

	public void testRecursive() throws Exception {
		// this is cool because the 3rd alt includes !(all other possibilities)
		Grammar g = new Grammar(
			"lexer grammar duh;\n" +
			"SUBTEMPLATE\n" +
			"        :       '{'\n" +
			"                ( SUBTEMPLATE\n" +
			"                | ESC\n" +
			"                | ~('}'|'\\\\'|'{')\n" +
			"                )*\n" +
			"                '}'\n" +
			"        ;\n" +
			"fragment\n" +
			"ESC     :       '\\\\' . ;");
		g.createLookaheadDFAs();
		String expecting =
			".s0-'\\\\'->:s3=>2\n" +
			".s0-'{'->:s2=>1\n" +
			".s0-'}'->:s1=>4\n" +
			".s0-{'\\u0000'..'[', ']'..'z', '|', '~'..'\\uFFFE'}->:s4=>3\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testRecursive2() throws Exception {
		// this is also cool because it resolves \\ to be ESC alt; it's just
		// less efficient of a DFA
		Grammar g = new Grammar(
			"lexer grammar duh;\n" +
			"SUBTEMPLATE\n" +
			"        :       '{'\n" +
			"                ( SUBTEMPLATE\n" +
			"                | ESC\n" +
			"                | ~('}'|'{')\n" +
			"                )*\n" +
			"                '}'\n" +
			"        ;\n" +
			"fragment\n" +
			"ESC     :       '\\\\' . ;");
		g.createLookaheadDFAs();
		String expecting =
			".s0-'\\\\'->.s3\n" +
			".s0-'{'->:s2=>1\n" +
			".s0-'}'->:s1=>4\n" +
			".s0-{'\\u0000'..'[', ']'..'z', '|', '~'..'\\uFFFE'}->:s5=>3\n" +
			".s3-'\\\\'->:s8=>2\n" +
			".s3-'{'->:s7=>2\n" +
			".s3-'}'->.s4\n" +
			".s3-{'\\u0000'..'[', ']'..'z', '|', '~'..'\\uFFFE'}->:s6=>2\n" +
			".s4-'\\u0000'..'\\uFFFE'->:s6=>2\n" +
			".s4-<EOT>->:s5=>3\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNotFragmentInLexer() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar T;\n"+
			"A : 'a' | ~B {;} ;\n" +
			"fragment B : 'a' ;\n");
		g.createLookaheadDFAs();
		String expecting =
			".s0-'a'->:s1=>1\n" +
			".s0-{'\\u0000'..'`', 'b'..'\\uFFFE'}->:s2=>2\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNotSetFragmentInLexer() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar T;\n"+
			"A : B | ~B {;} ;\n" +
			"fragment B : 'a'|'b' ;\n");
		g.createLookaheadDFAs();
		String expecting =
			".s0-'a'..'b'->:s1=>1\n" +
			".s0-{'\\u0000'..'`', 'c'..'\\uFFFE'}->:s2=>2\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNotTokenInLexer() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar T;\n"+
			"A : 'x' ('a' | ~B {;}) ;\n" +
			"B : 'a' ;\n");
		g.createLookaheadDFAs();
		String expecting =
			".s0-'a'->:s1=>1\n" +
			".s0-{'\\u0000'..'`', 'b'..'\\uFFFE'}->:s2=>2\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNotComplicatedSetRuleInLexer() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar T;\n"+
			"A : B | ~B {;} ;\n" +
			"fragment B : 'a'|'b'|'c'..'e'|C ;\n" +
			"fragment C : 'f' ;\n"); // has to seen from B to C
		g.createLookaheadDFAs();
		String expecting =
			".s0-'a'..'f'->:s1=>1\n" +
			".s0-{'\\u0000'..'`', 'g'..'\\uFFFE'}->:s2=>2\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testNotSetWithRuleInLexer() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar T;\n"+
			"T : ~('a' | B) | 'a';\n" +
			"fragment\n" +
			"B : 'b' ;\n" +
			"C : ~'x'{;} ;"); // force Tokens to not collapse T|C
		g.createLookaheadDFAs();
		String expecting =
			".s0-'b'->:s3=>2\n" +
			".s0-'x'->:s2=>1\n" +
			".s0-{'\\u0000'..'a', 'c'..'w', 'y'..'\\uFFFE'}->.s1\n" +
			".s1-<EOT>->:s2=>1\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testSetCallsRuleWithNot() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar A;\n" +
			"T : ~'x' ;\n" +
			"S : 'x' (T | 'x') ;\n");
		g.createLookaheadDFAs();
		String expecting =
			".s0-'x'->:s2=>2\n" +
			".s0-{'\\u0000'..'w', 'y'..'\\uFFFE'}->:s1=>1\n";
		checkDecision(g, 1, expecting, null);
	}

	public void testSynPredInLexer() throws Exception {
		Grammar g = new Grammar(
			"lexer grammar T;\n"+
			"LT:  '<' ' '*\n" +
			"  |  ('<' IDENT) => '<' IDENT '>'\n" + // this was causing syntax error
			"  ;\n" +
			"IDENT:    'a'+;\n");
		// basically, Tokens rule should not do set compression test
		g.createLookaheadDFAs();
		String expecting =
			".s0-'<'->:s1=>1\n" +
			".s0-'a'->:s2=>2\n";
		checkDecision(g, 4, expecting, null); // 4 is Tokens rule
	}

	// S U P P O R T

	public void _template() throws Exception {
		Grammar g = new Grammar(
			"grammar T;\n"+
			"a : A | B;");
		g.createLookaheadDFAs();
		String expecting =
			"\n";
		checkDecision(g, 1, expecting, null);
	}

	protected void checkDecision(Grammar g,
								 int decision,
								 String expecting,
								 int[] expectingUnreachableAlts)
		throws Exception
	{

		// mimic actions of org.antlr.Tool first time for grammar g
		if ( g.getCodeGenerator()==null ) {
			CodeGenerator generator = new CodeGenerator(null, g, "Java");
			g.setCodeGenerator(generator);
			g.createNFAs();
			g.createLookaheadDFAs();
		}

		DFA dfa = g.getLookaheadDFA(decision);
		assertNotNull("unknown decision #"+decision, dfa);
		FASerializer serializer = new FASerializer(g);
		String result = serializer.serialize(dfa.startState);
		//System.out.print(result);
		List nonDetAlts = dfa.getUnreachableAlts();
		//System.out.println("alts w/o predict state="+nonDetAlts);

		// first make sure nondeterministic alts are as expected
		if ( expectingUnreachableAlts==null ) {
			if ( nonDetAlts.size()!=0 ) {
				System.err.println("nondeterministic alts (should be empty): "+nonDetAlts);
			}
			assertEquals("unreachable alts mismatch", 0, nonDetAlts.size());
		}
		else {
			for (int i=0; i<expectingUnreachableAlts.length; i++) {
				assertTrue("unreachable alts mismatch", nonDetAlts.contains(new Integer(expectingUnreachableAlts[i])));
			}
		}
		assertEquals(expecting, result);
	}

}