Question

Exercise 1: Writing Assert Based Black Box Unit Tests for a Queue For this exercise you will need a copy of Queue.h, the queue interface for this exercise. You can download it or use the following command to copy it into your current directory cp «dp1091/public_html/2012/tlb/11/Queue.h. And a copy of the testQueue.c, the testing code we have provided to help get you started. You can download it or use the following command to copy it into your current directory cp «dp1091/public_html/2012/tlb/11/testQueue.c. It is a good idea to write tests for your ADT before you have even implemented it to make sure you understand exactly how the ADT should behave. In this exercise you are going to write tests for a queue ADT. Your tests should test the required behaviour of the queue. It should rely only on the functions and typedefs from the Queue.h file. To get you started we have supplied you with a testQueue.c file, but you need to add more tests of your own. Since the tests are not a complete program on their own, you will not be able to run your tests yet, but you can compile them to check your syntax using the following: dcc -c testQueue.c

typedef struct queue * Queue;


Queue queueCreate(int maxSize);
void enqueue(Queue q, int item);
int queueFront(Queue q);
int dequeue(Queue q);
int queueSize(Queue q);
void queueDestroy(Queue q)

Answer 1

/*
* Queue.h
*
* Created on: 28-Jul-2020
* Author: naren
*/

#ifndef SRC_QUEUE_H_
#define SRC_QUEUE_H_
#include <stdio.h>
#include <stdlib.h>

/**
* structure for queue
* *array to store items
* capacity maxSize of queue
*/
struct queue{
   int *array;
   int capacity;
   int front;
   int rear;
};

typedef struct queue *Queue;

/**
* function to create queue of given size
*/
Queue queueCreate(int maxSize);

/**
* function to enqueue an item into queue
*/
void enqueue(Queue q, int item);

/**
* function to get an item from front of the queue
*/
int queueFront(Queue q);

/**
* function to dequeue an item from the queue
*/
int dequeue(Queue q);

/**
* function to get size of the given queue
*/
int queueSize(Queue q);

/**
* function to destroy given queue
*/
void queueDestroy(Queue q);

#endif /* SRC_QUEUE_H_ */

/*
* Queue.cpp
*
* Created on: 28-Jul-2020
* Author: naren
*/

#include "Queue.h"

Queue queueCreate(int maxSize){
   Queue q = (Queue) malloc(sizeof(struct queue));
   q->array = (int *) malloc(sizeof(int) * maxSize);
   q->front = -1;
   q->rear = -1;
   q->capacity = maxSize;
   return q;
}

void enqueue(Queue q, int item){
   if (q->rear +1 != q->capacity){
       if (q->rear == -1){
           q->front++;
       }
       q->rear++;
       q->array[q->rear] = item;
   }
}

int queueFront(Queue q){
   if (q->front == -1){
       return -1;
   }
   return q->array[q->front];
}

int dequeue(Queue q){
   int front = q->array[q->front];
   q->front++;
   if (q->front > q->rear){
       q->front = -1;
       q->rear = -1;
   }
   return front;
}

int queueSize(Queue q){
   if(q->front == -1){
       return 0;
   }

   return (q->rear - q->front + 1);
}
void queueDestroy(Queue q){
   free(q);
}

/*
* testQueue.c
*
* this is my testQueue file. you can use your own
*
* Created on: 28-Jul-2020
* Author: naren
*/
#include "Queue.h"

int main(){
   // create a queue
   Queue q = queueCreate(5);
   enqueue(q, 23);
   enqueue(q, 20);
   enqueue(q, 34);

   // test for function queueSize
   if (queueSize(q) == 3){
       printf("test Queue size passed.\n");
   } else {
       printf("test Queue size failed.\n");
   }

   // test for function queueFront
   if (queueFront(q) == 23){
       printf("test Queue front passed.\n");
   } else{
       printf("test Queue front failed.\n");
   }

   // test for function dequeue;
   dequeue(q);
   if (queueFront(q) == 20){
       printf("test deQueue passed.\n");
   } else{
       printf("test deQueue front failed.\n");
   }

   queueDestroy(q);
}

Output:

test Queue size passed. test Queue front passed. test deQueue passed.