Fikset feil i kode og test

modules-template/core/src/main/java/core/Calc.java

@@ -37,7 +37,7 @@ public class Calc {
      * @throws IllegalArgumentException if n is larger than the operand count
      */
     public double peekOperand(int n) {
-        if (n > getOperandCount()) {
+        if (n >= getOperandCount()) {
             throw new IllegalArgumentException("Cannot peek at position " + n + " when the operand count is " + getOperandCount());
         }
         return operandStack.get(getOperandCount() - n - 1);

modules-template/core/src/test/java/core/CalcTest.java

@@ -86,10 +86,11 @@ public class CalcTest {
     @Test
     public void testSwap() {
         Calc calc = new Calc(1.0, 3.14);
-        calc.swap();
         checkCalc(calc, 3.14, 1.0);
         calc.swap();
         checkCalc(calc, 1.0, 3.14);
+        calc.swap();
+        checkCalc(calc, 3.14, 1.0);
     }
 
     @Test