Add new file InsertionSortTest

InsertionSortTest.java

+import org.junit.Test;
+import static org.junit.Assert.assertArrayEquals;
+
+public class InsertionSortTest {
+
+    @Test
+    public void testInsertionSort() {
+        int[] unsortedArray = {7, 98, 15, 38, 25, 0, 12, 8, 22, 83, 79, 77, 63, 56, 56, 2, 18, 21, 24, 28};
+        int[] expectedSortedArray = {0, 2, 7, 8, 12, 15, 18, 21, 22, 24, 25, 28, 38, 56, 56, 63, 77, 79, 83, 98};
+
+        // Test randomFill method
+        InsertionSort.randomFill(unsortedArray);
+        // Ensure the array is filled with random numbers between 0 and 99
+        for (int num : unsortedArray) {
+            assertTrue(num >= 0 && num < 100);
+        }
+
+        // Test insertionSort method
+        InsertionSort.insertionSort(unsortedArray);
+        // Ensure the array is sorted correctly
+        assertArrayEquals(expectedSortedArray, unsortedArray);
+    }
+}