Changes done in tests for BAEL-876 (#1843)

* Correction in first two tests

* Add new test

for RecursionWithCorrectTerminationCondition

* BAEL-876 Removed static method qualifier

core-java/src/main/java/com/baeldung/stackoverflowerror/RecursionWithCorrectTerminationCondition.java

@@ -1,7 +1,7 @@
 package com.baeldung.stackoverflowerror;
 
 public class RecursionWithCorrectTerminationCondition {
-    public static int calculateFactorial(final int number) {
+    public int calculateFactorial(final int number) {
         return number <= 1 ? 1 : number * calculateFactorial(number - 1);
     }
 }

core-java/src/test/java/com/baeldung/stackoverflowerror/InfiniteRecursionWithTerminationConditionManualTest.java

@@ -6,7 +6,7 @@ import org.junit.Test;
 
 public class InfiniteRecursionWithTerminationConditionManualTest {
     @Test
-    public void givenPositiveIntNoOne_whenCalcFact_thenThrowsException() {
+    public void givenPositiveIntNoOne_whenCalcFact_thenCorrectlyCalc() {
         int numToCalcFactorial = 1;
         InfiniteRecursionWithTerminationCondition irtc = new InfiniteRecursionWithTerminationCondition();
 
@@ -14,7 +14,7 @@ public class InfiniteRecursionWithTerminationConditionManualTest {
     }
 
     @Test
-    public void givenPositiveIntGtOne_whenCalcFact_thenThrowsException() {
+    public void givenPositiveIntGtOne_whenCalcFact_thenCorrectlyCalc() {
         int numToCalcFactorial = 5;
         InfiniteRecursionWithTerminationCondition irtc = new InfiniteRecursionWithTerminationCondition();
 

core-java/src/test/java/com/baeldung/stackoverflowerror/RecursionWithCorrectTerminationConditionManualTest.java

@@ -0,0 +1,15 @@
+package com.baeldung.stackoverflowerror;
+
+import static junit.framework.TestCase.assertEquals;
+
+import org.junit.Test;
+
+public class RecursionWithCorrectTerminationConditionManualTest {
+    @Test
+    public void givenNegativeInt_whenCalcFact_thenCorrectlyCalc() {
+        int numToCalcFactorial = -1;
+        RecursionWithCorrectTerminationCondition rctc = new RecursionWithCorrectTerminationCondition();
+
+        assertEquals(1, rctc.calculateFactorial(numToCalcFactorial));
+    }
+}