fix: remove memory leak in queue

data_structures/test_queue.cpp

@@ -1,41 +1,93 @@
-#include <iostream>
-#include <string>
+#include <cassert>  /// for assert
+#include <iostream> /// for std::cout
 
-#include "./queue.h"
+#include "./queue.hpp"
+
+template <typename T>
+void testConstructedQueueIsEmpty() {
+    const queue<T> curQueue;
+    assert(curQueue.isEmptyQueue());
+}
+
+void testEnQueue() {
+    queue<int> curQueue;
+    curQueue.enQueue(10);
+    assert(curQueue.toVector() == std::vector<int>({10}));
+    curQueue.enQueue(20);
+    assert(curQueue.toVector() == std::vector<int>({10, 20}));
+    curQueue.enQueue(30);
+    curQueue.enQueue(40);
+    assert(curQueue.toVector() == std::vector<int>({10, 20, 30, 40}));
+}
+
+void testDeQueue() {
+    queue<int> curQueue;
+    curQueue.enQueue(10);
+    curQueue.enQueue(20);
+    curQueue.enQueue(30);
+
+    curQueue.deQueue();
+    assert(curQueue.toVector() == std::vector<int>({20, 30}));
+
+    curQueue.deQueue();
+    assert(curQueue.toVector() == std::vector<int>({30}));
+
+    curQueue.deQueue();
+    assert(curQueue.isEmptyQueue());
+}
+
+void testFront() {
+    queue<int> curQueue;
+    curQueue.enQueue(10);
+    assert(curQueue.front() == 10);
+    curQueue.enQueue(20);
+    assert(curQueue.front() == 10);
+}
+
+void testQueueAfterClearIsEmpty() {
+    queue<int> curQueue;
+    curQueue.enQueue(10);
+    curQueue.enQueue(20);
+    curQueue.enQueue(30);
+    curQueue.clear();
+    assert(curQueue.isEmptyQueue());
+}
+
+void testFrontThrowsAnInvalidArgumentWhenQueueEmpty() {
+    const queue<int> curQueue;
+    bool wasException = false;
+    try {
+        curQueue.front();
+    } catch (const std::invalid_argument&) {
+        wasException = true;
+    }
+    assert(wasException);
+}
+
+void testDeQueueThrowsAnInvalidArgumentWhenQueueEmpty() {
+    queue<int> curQueue;
+    bool wasException = false;
+    try {
+        curQueue.deQueue();
+    } catch (const std::invalid_argument&) {
+        wasException = true;
+    }
+    assert(wasException);
+}
 
 int main() {
-    queue<std::string> q;
-    std::cout << "---------------------- Test construct ----------------------"
-              << std::endl;
-    q.display();
-    std::cout
-        << "---------------------- Test isEmptyQueue ----------------------"
-        << std::endl;
-    if (q.isEmptyQueue())
-        std::cout << "PASS" << std::endl;
-    else
-        std::cout << "FAIL" << std::endl;
-    std::cout << "---------------------- Test enQueue ----------------------"
-              << std::endl;
-    std::cout << "After Hai, Jeff, Tom, Jkingston go into queue: " << std::endl;
-    q.enQueue("Hai");
-    q.enQueue("Jeff");
-    q.enQueue("Tom");
-    q.enQueue("Jkingston");
-    q.display();
-    std::cout << "---------------------- Test front ----------------------"
-              << std::endl;
-    std::string value = q.front();
-    if (value == "Hai")
-        std::cout << "PASS" << std::endl;
-    else
-        std::cout << "FAIL" << std::endl;
-    std::cout << "---------------------- Test deQueue ----------------------"
-              << std::endl;
-    q.display();
-    q.deQueue();
-    q.deQueue();
-    std::cout << "After Hai, Jeff left the queue: " << std::endl;
-    q.display();
+    testConstructedQueueIsEmpty<int>();
+    testConstructedQueueIsEmpty<double>();
+    testConstructedQueueIsEmpty<std::vector<long double>>();
+
+    testEnQueue();
+    testDeQueue();
+
+    testQueueAfterClearIsEmpty();
+
+    testFrontThrowsAnInvalidArgumentWhenQueueEmpty();
+    testDeQueueThrowsAnInvalidArgumentWhenQueueEmpty();
+
+    std::cout << "All tests pass!\n";
     return 0;
 }