Add new unit and integration tests (fc63776)

Author: d1niss

liquidjava-verifier/src/test/java/liquidjava/ast/opt/TestOptimizationInt.java

@@ -1,11 +1,13 @@
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 
 import org.junit.Test;
 
 import liquidjava.rj_language.ast.BinaryExpression;
 import liquidjava.rj_language.ast.LiteralInt;
 import liquidjava.rj_language.opt.ConstantFolding;
 import liquidjava.rj_language.opt.derivation_node.ValDerivationNode;
+import liquidjava.rj_language.ast.Var;
 
 public class TestOptimizationInt {
     @Test
@@ -15,4 +17,20 @@ public void testIntegerAddFold() {
         ValDerivationNode r = ConstantFolding.fold(new ValDerivationNode(b, null));
         assertEquals(new LiteralInt(5), r.getValue());
     }
+
+    @Test
+    public void testNoFoldWhenNonLiteral() {
+        BinaryExpression b = new BinaryExpression(new LiteralInt(1), "+", new Var("x"));
+        ValDerivationNode r = ConstantFolding.fold(new ValDerivationNode(b, null));
+        assertNotNull(r);
+    }
+
+    @Test
+    public void testIntegerSubFold() {
+        BinaryExpression b = new BinaryExpression(new LiteralInt(5), "-", new LiteralInt(2));
+        ValDerivationNode r = ConstantFolding.fold(new ValDerivationNode(b, null));
+        assertEquals(new LiteralInt(3), r.getValue());
+    }
+
+    
 }