Added tests for PriorityQueueSort

Author: Rahul-150705

src/test/java/com/thealgorithms/sorts/PriorityQueueSortTest.java

@@ -0,0 +1,42 @@
+package com.thealgorithms.sorts;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import org.junit.jupiter.api.Test;
+
+class PriorityQueueSortTest {
+
+    @Test
+    void testSortNormalArray() {
+        int[] input = {7, 2, 9, 4, 1};
+        int[] expected = {1, 2, 4, 7, 9};
+        assertArrayEquals(expected, PriorityQueueSort.sort(input));
+    }
+
+    @Test
+    void testEmptyArray() {
+        int[] input = {};
+        int[] expected = {};
+        assertArrayEquals(expected, PriorityQueueSort.sort(input));
+    }
+
+    @Test
+    void testNegativeNumbers() {
+        int[] input = {3, -1, 2, -5, 0};
+        int[] expected = {-5, -1, 0, 2, 3};
+        assertArrayEquals(expected, PriorityQueueSort.sort(input));
+    }
+
+    @Test
+    void testAlreadySortedArray() {
+        int[] input = {1, 2, 3, 4, 5};
+        int[] expected = {1, 2, 3, 4, 5};
+        assertArrayEquals(expected, PriorityQueueSort.sort(input));
+    }
+
+    @Test
+    void testArrayWithDuplicates() {
+        int[] input = {5, 1, 3, 3, 2, 5};
+        int[] expected = {1, 2, 3, 3, 5, 5};
+        assertArrayEquals(expected, PriorityQueueSort.sort(input));
+    }
+}