Fixed unhandled LTL parse error exception

src/main/java/de/tlc4b/TLC4B.java

@@ -37,7 +37,7 @@ public class TLC4B {
 	private String ltlFormula;
 	private String constantsSetup;
 
-	public static void main(String[] args) throws IOException {
+	public static void main(String[] args) {
 		System.setProperty("apple.awt.UIElement", "true"); // avoiding pop up
 															// windows
 		TLC4B tlc4b = new TLC4B();
@@ -52,6 +52,10 @@ public class TLC4B {
 			System.out.println("Model checking time: 0 sec");
 			System.out.println("Result: " + e.getError());
 			return;
+		} catch (IOException e) {
+			System.err.println(e.getMessage());
+			System.out.println("Model checking time: 0 sec");
+			System.out.println("Result: " + "I/O Error");
 		}
 
 		if (TLC4BGlobals.isRunTLC()) {

src/main/java/de/tlc4b/ltl/LTLFormulaVisitor.java

@@ -163,7 +163,7 @@ public class LTLFormulaVisitor extends DepthFirstAdapter {
 		try {
 			start = parser.parse(bPredicate, false);
 		} catch (BException e) {
-			e.printStackTrace();
+			throw new LTLParseException(e.getMessage());
 		}
 
 		return start;

src/test/java/de/tlc4b/tlc/integration/BasicsTest.java → src/test/java/de/tlc4b/tlc/integration/BasicTest.java

@@ -18,12 +18,12 @@ import static de.tlc4b.tlc.TLCResults.TLCResult.NoError;
 import static de.tlc4b.util.TestUtil.test;
 
 @RunWith(PolySuite.class)
-public class BasicsTest extends AbstractParseMachineTest {
+public class BasicTest extends AbstractParseMachineTest {
 
 	private final File machine;
 	private final TLCResult error;
 
-	public BasicsTest(File machine, TLCResult result) {
+	public BasicTest(File machine, TLCResult result) {
 		this.machine = machine;
 		this.error = result;
 	}

src/test/java/de/tlc4b/tlc/integration/BugTest.java

+package de.tlc4b.tlc.integration;
+
+import org.junit.Test;
+
+import de.tlc4b.TLC4B;
+
+public class BugTest {
+
+	@Test
+	public void testTraceValues() {
+		String[] a = new String[] { "./src/test/resources/bugs/LTLParseError.mch" };
+		TLC4B.main(a);
+	}
+
+}
\ No newline at end of file

src/test/resources/bugs/LTLParseError.mch

+MACHINE Test
+DEFINITIONS
+ ASSERT_LTL_1 == "G(!a.({a:ID & a==aa} => F{a : xx}))"
+SETS
+ ID={aa,bb}
+CONSTANTS iv
+PROPERTIES
+ iv:ID
+VARIABLES xx
+INVARIANT
+ xx:POW(ID)
+INITIALISATION xx:={}
+OPERATIONS
+  Set(yy) = SELECT yy:ID & yy /:xx THEN xx:= xx \/ {yy} END
+END
+