Type checker correction for "while true" loops, fixes #210

overturetool · Jan 2, 2014 · e569eeb · e569eeb
1 parent 7612264
commit e569eeb
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Showing 2 changed files with 25 additions and 3 deletions.
diff --git a/core/typechecker/src/main/java/org/overture/typechecker/visitor/TypeCheckerStmVisitor.java b/core/typechecker/src/main/java/org/overture/typechecker/visitor/TypeCheckerStmVisitor.java
@@ -12,6 +12,7 @@
 import org.overture.ast.definitions.AInstanceVariableDefinition;
 import org.overture.ast.definitions.PDefinition;
 import org.overture.ast.definitions.SClassDefinition;
+import org.overture.ast.expressions.ABooleanConstExp;
 import org.overture.ast.expressions.AIntLiteralExp;
 import org.overture.ast.expressions.ARealLiteralExp;
 import org.overture.ast.expressions.AVariableExp;
@@ -1010,8 +1011,30 @@ public PType caseAWhileStm(AWhileStm node, TypeCheckInfo question)
 	{
 		question.qualifiers = null;
 		node.getExp().apply(THIS, question);
-		node.setType(node.getStatement().apply(THIS, question));
-		return node.getType();
+		PType stype = node.getStatement().apply(THIS, question);
+
+		if (node.getExp() instanceof ABooleanConstExp && stype instanceof AUnionType)
+		{
+			ABooleanConstExp boolLiteral = (ABooleanConstExp)node.getExp();
+
+			if (boolLiteral.getValue().getValue())	// while true do...
+			{
+				List<PType> edited = new Vector<PType>();
+				AUnionType original = (AUnionType)stype;
+
+				for (PType t: original.getTypes())
+				{
+					if (!(t instanceof AVoidType))
+					{
+						edited.add(t);
+					}
+				}
+
+				stype = AstFactory.newAUnionType(node.getLocation(), edited);
+			}
+		}
+
+		return stype;
 	}
 
 	@Override

diff --git a/core/typechecker/src/test/resources/classes/CodegenPP.result b/core/typechecker/src/test/resources/classes/CodegenPP.result
@@ -9,7 +9,6 @@
 <message column="12" line="2170" message="Operation returns void value" messageType="error" number="3313" resource="CodegenPP.result"/>
 <message column="12" line="2180" message="Operation returns void value" messageType="error" number="3313" resource="CodegenPP.result"/>
 <message column="12" line="2197" message="Operation returns void value" messageType="error" number="3313" resource="CodegenPP.result"/>
-<message column="9" line="2247" message="Operation returns void value" messageType="error" number="3313" resource="CodegenPP.result"/>
 <message column="9" line="2338" message="Operation '(e.hasDeflt)' cannot be called from a function" messageType="error" number="3300" resource="CodegenPP.result"/>
 <message column="5" line="2356" message="Operation '(letExp.getDefs)' cannot be called from a function" messageType="error" number="3300" resource="CodegenPP.result"/>
 <message column="41" line="2388" message="Operation '(selif.getTest)' cannot be called from a function" messageType="error" number="3300" resource="CodegenPP.result"/>