properly check for grammar/filename difference

CHANGES.txt

@@ -4,6 +4,7 @@ November 17, 2012
 
 * .tokens files goes in output dir like parser file.
 * added check: action in lexer rules must be last element of outermost alt
+* properly check for grammar/filename difference
 
 November 11, 2012
 

tool/playground/T.g

@@ -1,8 +1,3 @@
 grammar T;
-s : A ;
+s : EOF ;
 
-A : 'a' ;
-
-B : 'x' -> skip |'y' ;
-
-WS : [ \t\r\n]+ -> skip ;

tool/src/org/antlr/v4/Tool.java

@@ -367,6 +367,7 @@ public class Tool {
 			if ( lexerAST!=null ) {
 				lexerg = new LexerGrammar(this, lexerAST);
 				lexerg.fileName = g.fileName;
+				lexerg.originalGrammar = g;
 				g.implicitLexer = lexerg;
 				lexerg.implicitLexerOwner = g;
 				processNonCombinedGrammar(lexerg, gencode);

tool/src/org/antlr/v4/semantics/BasicSemanticChecks.java

@@ -248,10 +248,10 @@ public class BasicSemanticChecks extends GrammarTreeVisitor {
 	// They are triggered by the visitor methods above.
 
 	void checkGrammarName(Token nameToken) {
-		if ( g.implicitLexer==null ) return;
 		String fullyQualifiedName = nameToken.getInputStream().getSourceName();
 		File f = new File(fullyQualifiedName);
 		String fileName = f.getName();
+		if ( g.originalGrammar!=null ) return; // don't warn about diff if this is implicit lexer
 		if ( !Utils.stripFileExtension(fileName).equals(nameToken.getText()) &&
 		     !fileName.equals(Grammar.GRAMMAR_FROM_STRING_NAME)) {
 			g.tool.errMgr.grammarError(ErrorType.FILE_AND_GRAMMAR_NAME_DIFFER,

tool/src/org/antlr/v4/tool/Grammar.java

@@ -121,10 +121,13 @@ public class Grammar implements AttributeResolver {
     public String fileName;
 
     /** Was this parser grammar created from a COMBINED grammar?  If so,
-	 *  this is what we derived.
+	 *  this is what we extracted.
 	 */
     public LexerGrammar implicitLexer;
 
+	/** If this is an extracted/implicit lexer, we point at original grammar */
+	public Grammar originalGrammar;
+
     /** If we're imported, who imported us? If null, implies grammar is root */
     public Grammar parent;
     public List<Grammar> importedGrammars;