我的记忆泄漏在哪里

所以我编写了自己的ArrayList实现（又名C++中的向量），并在其中包含了几种算法。现在我的合并排序方法似乎泄漏了内存，但是我已经逐行检查了代码，跟踪了删除的分配，一切似乎都进展顺利！

应该注意，我有一个 ArrayList 中每个方法的测试脚本，我遇到了崩溃，然后我尝试删除合并排序测试，然后繁荣，不再崩溃。但有趣的是...它并不总是崩溃，它有时会工作，它会崩溃其他人。

这两种方法的代码如下：

快速变量枚举：

array = 支持数组列表的数组

size = 跟踪数组大小的整数。

sort = 指示列表是否已排序的布尔值

/**
 * Runs merge sort on this ArrayList<T>. Interface function to the central,
 * recursive, merge sort function.
 *
 * Runs in O(nlogn) time. However it consumes extra memory.
 */
template<class T>
void ArrayList<T>::mergeSort() {
    T* temp = mergeSort(array, size);
    delete [] array;
    array = temp;
    sorted = true;
}
/**
 * Runs merge sort on the passed in array. Recursive.
 *
 * Runs in O(nlogn) time. However it consumes extra memory.
 *
 * @param array the array to sort.
 * @param arraySize the size of the array that is to be sorted.
 * @return the sorted array.
 */
template<class T>
T* ArrayList<T>::mergeSort(T* array, int arraySize) {
    T* returnArray;
    //If the array is more than one element.
    if (arraySize > 1) {
        int size1 = arraySize / 2;
        int size2 = arraySize - size1;
        T* array1;
        T* array2;
        //Recurse.
        array1 = mergeSort(array, size1);
        array2 = mergeSort(array + size1, size2);
        //Allocate memory for return array.
        returnArray = new T[arraySize];
        //Loop through all elements in returnArray.
        int i = 0, j = 0, k = 0;
        while (i < arraySize) {
            //Place the lesser of two elements in returnArray.
            if ((array1[j] <= array2[k] && j < size1)
                    || k == size2) {
                returnArray[i] = array1[j];
                j++;
            }
            else {
                returnArray[i] = array2[k];
                k++;
            }
            i++;
        }
        //Free the memory allocated in the recursive calls.
        delete [] array1;
        delete [] array2;
        array1 = 0;
        array2 = 0;
    }
    //If one element is in the passed array.
    else {
        //Allocate memory for new array, and assign passed value to it.
        //This is done so delete can be called in the calling function.
        returnArray = new T[1];
        returnArray[0] = array[0];
    }
    return returnArray;
}