lab04 : C++ Big-Three Review

Goals

By the end of this lab, given a description of a class containing data members that point to structures on the heap, you will be able to:

• write a correct copy constructor for the class
• write a correct destructor for the class
• write a correct assignment operator for the class

Step-by-Step

Step 1: Get the lab04 starter code into your repository directory

In this step, we are going to copy the lab04 starter files from the instructors directory into your ~/cs32/lab04 directory.

The files are in the instructors directory at

~aduncan/public_html/cs32/s17/labs/lab04/*

The * here stands in as a “wildcard” that matches “all files”.

You want to copy these files into your ~/cs32/lab04 directory.

By now you should know (or remember) how to copy files; if you need a refresher, see earlier labs.

Step 2: Getting the test cases to pass for lab04!

Now, we are ready to to work on lab04.

In this week’s lab, you have the following files:

• Makefile
• student.h, student.cpp
• studentRoll.h, studentRoll.cpp
• studentTest00.cpp, etc.
• studentRollTest00.cpp, etc.

Your job is, as usual, get all the test cases to pass. This involves implementing the “big three”: Copy Constructor, Overloaded Assignment Operator, and Destructor.

In addition to the regular test cases, there are also “leakTests”.
This involves running a utility called valgrind on your code to see whether there are any memory leaks, or other problems involving memory management. You will only pass the tests if your code has proper memory management.

You will submit only the student.cpp and studentRoll.cpp files.
As a result, there are two quite annoying things that you’ll just have to put up with:

• In the Student class, the name attribute is implemented with a C-string that is allocated with dynamic memory on the heap. This is annoying. Your might prefer to use the std::string class.
  Of course you would. But, that’s not the point of this assignment.
  The point of this assignment is to know whether you can manage memory properly.

• In the StudentRoll class, the list of students is a linked list of structs rather than an std::list<Student> or std::vector<Student> or something.
  This is indeed annoying. Tough. We are training you for the situation where you don’t have any choice, but have to work with the data structures you are given.

In certain later assignments, you will be given the freedom to choose whatever data structure or implementation is appropriate. You’ll be able to decide whether to use std::string, or C-strings, whether to use array or std::vector, etc. This is not one of those assignments.

Suggested way to proceed

I suggest proceeding in the following steps:

• (0) Look at the tests in testStudent00.cpp. You may want to get the simple tests to pass first, including the test for toString(). Run make testStudent00 to compile this file, and then run ./testStudent00 to run the tests. Iterate until the tests for testStudent00 pass.
• (1) Repeat for testStudent01.cpp, etc.
  • To get these to pass, you need to implement, possibly among other things, the Copy Constructor and Overloaded Assignment Operator for Student
• (2) Then, try to get the leak tests to pass as they pertain to Student, i.e.
  • make lts00
  • make lts01
  • make lts02
  • make lts03
  • This will require implementing the destructor for Student
• (3) Work on each test file for StudentRoll, getting those tests to pass, i.e. testStudentRoll00.cpp, testStudentRoll01.cpp, etc.
  • To get these to pass, you need to implement, possibly among other things, the Copy Constructor and Overloaded Assignment Operator for StudentRoll
• (4) Then, try to get the leak tests for StudentRoll to pass, i.e.
  • make ltsr00
  • make ltsr01
  • make ltsr02
  • This will require implementing the destructor for StudentRoll

How do I know if I’m done?

When you are done, you should be able to do both of the following, and see no error messages:

make tests
make leaktests

Step 3: Submission

To submit, use:

~submit/submit -p 739 student.cpp studentRoll.cpp

Grading

• (300 pts) Test cases on submit.cs, as indicated on that system.