better handling of cross references in xtext-to-antlr transformation

Author: amlajmi

plugins/org.dslforge.xtext.generator/src/org/dslforge/xtext/generator/web/parser/GenGrammar.xtend

@@ -15,8 +15,11 @@
  */
 package org.dslforge.xtext.generator.web.parser
 
+import java.util.Arrays
+import java.util.HashSet
 import java.util.Iterator
 import java.util.List
+import java.util.Set
 import java.util.regex.Matcher
 import java.util.regex.Pattern
 import org.dslforge.common.AbstractGenerator
@@ -39,6 +42,7 @@ import org.eclipse.xtext.TerminalRule
 import org.eclipse.xtext.XtextFactory
 import org.eclipse.xtext.resource.SaveOptions
 import org.eclipse.xtext.resource.XtextResource
+import org.eclipse.xtext.RuleCall
 
 class GenGrammar extends AbstractGenerator {
 
@@ -91,7 +95,6 @@ class GenGrammar extends AbstractGenerator {
 		val appendable = createAppendable()
 		var grammarDefinition = grammar.eResource as XtextResource
 		val rules = grammar.rules
-
 		// rename rules
 		var List<ParserRule> parserRules = GrammarUtil::allParserRules(grammar);
 		for (ParserRule pr : parserRules) {
@@ -101,23 +104,22 @@ class GenGrammar extends AbstractGenerator {
 		for (EnumRule en : enumRules) {
 			en.setName("rule_" + en.name.toFirstUpper)
 		}
-		parserRules = GrammarUtil::allParserRules(grammar);
 		for (ParserRule pr : parserRules) {
-			// rules on the client side are untyped
+			// rules are untyped
 			println(pr)
-			pr.setType(null)
-			//remove semantic predicates
+			pr.setType(null)	
+			//semantic predicates
 			var List<AbstractElement> elements = GrammarUtil::containedAbstractElements(pr)
 			for (AbstractElement e: elements)
-				e.predicated = false
-			// remove the actions (xtext-specific)
+				e.predicated = false	
+			// actions
 			val alternatives = pr.alternatives
 			if (alternatives instanceof Group) {
 				var List<AbstractElement> objs = (alternatives as Group).elements
 				var Iterator<AbstractElement> i = objs.iterator();
 				while (i.hasNext()) {
 					var o = i.next()
-					//remove actions
+					// actions
 					if (o instanceof Action) {
 						if (o.feature!=null)
 							i.remove();
@@ -133,37 +135,39 @@ class GenGrammar extends AbstractGenerator {
 				if (operator.equals("?=")) {
 					a.setOperator("=")
 				}
-				// cross references are not handled on the client side
-				// replace cross references in the form "reference=[Type|X]" to "reference=X" where X in {ID, STRING, FQN, ...}
+				// cross references
 				if (terminal instanceof CrossReference) {
 					var call = XtextFactory::eINSTANCE.createRuleCall
 					var replacement = XtextFactory::eINSTANCE.createTerminalRule
 					val allTerminalRules = GrammarUtil::allTerminalRules(grammar)
 					for (TerminalRule t: allTerminalRules) {
-						if (t.name=="ID")
-							replacement=t
+						var x = terminal.terminal
+						if (x instanceof RuleCall) {
+							var rule = (x as RuleCall).rule
+							if (t.name==rule.name)
+								replacement=t		
+						}
+
 					}
 					call.setRule(replacement)
 					a.setTerminal(call)
 				}
 			}
-			var text = grammarDefinition.serializer.serialize(pr, SaveOptions::defaultOptions)
-			// remove all the {Pattern.current=xxx}			 	 
+			var text = grammarDefinition.serializer.serialize(pr, SaveOptions::defaultOptions)		
+			// {Pattern.current=xxx}			 	 
 			val Pattern p = Pattern::compile("\\{(.+?)\\}")
 			val Matcher m = p.matcher(text)
 			while (m.find()) {
 			val group = m.group
 			if (!(group.substring(1, 2) == '\''))
 				text = text.replace(group, "")
-			}
-			// append EOF at the end of rule
+			}			
+			//EOF
 			if (rules.get(0).equals(pr))
 				text = text.substring(0, text.length - 1) + " EOF!" + ";"
 			text = text.replaceAll("\"", "'")
-			appendable.newLine.append(text + "\n").newLine
-
+			appendable.newLine.append(text + "\n")
 		}
-
 		// Manage enumerations
 		enumRules = GrammarUtil::allEnumRules(grammar);
 		for (EnumRule en : enumRules) {
@@ -181,9 +185,18 @@ class GenGrammar extends AbstractGenerator {
 				}
 			}
 			builder.append(";")
-			appendable.newLine.append(builder + "\n").newLine
+			appendable.newLine.append(builder + "\n")
+		}	
+		// Manage terminals
+		var terminalRules = GrammarUtil::allTerminalRules(grammar);
+		var Set<String> covered = new HashSet<String>(Arrays.asList("ID", "STRING", "COMMENT", "WS", "INT", "ML_COMMENT", "SL_COMMENT", "ANY_OTHER"));
+		for (TerminalRule terminal : terminalRules) {
+			if (!covered.contains(terminal.name)) {
+				var text = grammarDefinition.serializer.serialize(terminal, SaveOptions::defaultOptions)
+				text = text.replace("terminal ", "");
+				appendable.newLine.append(text + "\n");	
+			}
 		}
-
 		return appendable.content
 	}
 
@@ -196,13 +209,11 @@ class GenGrammar extends AbstractGenerator {
 
 		WS:  (' '|'\r'|'\t'|'\u000C'|'\n') {$channel=HIDDEN;} ;
 
-		//NUMBER: INT ('.' INT)?;
-		
 		INT: ('0'..'9')+;
 	'''
 
 	def StringAppendable createAppendable() {
 		val appendable = new StringAppendable(indentation, lineSeparator)
 		return appendable
 	}
-}
+}