GP-145 Fix resizeTable method to calculate HashTable size correctly

2-0-data-structures-and-algorithms/2-2-9-hash-table/src/main/java/com/bobocode/cs/HashTable.java

@@ -1,9 +1,9 @@
 package com.bobocode.cs;
 
-import static java.util.Objects.requireNonNull;
-
 import lombok.ToString;
 
+import static java.util.Objects.requireNonNull;
+
 /**
  * {@link HashTable} is a simple Hashtable-based implementation of {@link Map} interface with some additional methods.
  * It is based on the array of {@link Node} objects. Both {@link HashTable} and {@link Node} have two type parameters:
@@ -271,6 +271,7 @@ public String toString() {
     public void resizeTable(int newCapacity) {
         verifyCapacity(newCapacity);
         @SuppressWarnings("unchecked") Node<K, V>[] newTable = new Node[newCapacity];
+        size = 0;
         for (var head : table) {
             var current = head;
             while (current != null) {

2-0-data-structures-and-algorithms/2-2-9-hash-table/src/test/java/com/bobocode/cs/HashTableTest.java

@@ -503,10 +503,10 @@ class HashTableHelperMethodsTest {
         @Order(1)
         @DisplayName("resizeTable creates a new array and put there all elements")
         void resizeTable() {
-            addToTable("madmax", 833);
-            addToTable("altea", 553);
-            addToTable("AaAa", 123);
-            addToTable("BBBB", 456);
+            hashTable.put("madmax", 833);
+            hashTable.put("altea", 553);
+            hashTable.put("AaAa", 123);
+            hashTable.put("BBBB", 456);
 
             hashTable.resizeTable(16);
 
@@ -518,6 +518,20 @@ void resizeTable() {
         }
 
         @Test
+        @Order(2)
+        @DisplayName("resizeTable does not change the size")
+        void resizeTableDoesNotChangeSize() {
+            hashTable.put("madmax", 833);
+            hashTable.put("altea", 553);
+            hashTable.put("AaAa", 123);
+
+            hashTable.resizeTable(32);
+
+            assertThat(hashTable.size()).isEqualTo(3);
+        }
+
+        @Test
+        @Order(3)
         @DisplayName("toString returns a string that represents an underlying table")
         void toStringTest() {
             addToTable("madmax", 833);