Experiments with CVS modules

I have a plan to refactor the lab exercises for EG-140 in readiness for automated submission and marking. The first step was to put the BlueJ projects that students upload into a new repository. However I wanted the repository to be such that all the projects would be within the eg-140-laboratory project but different subsets could be delivered to various audiences. For example, students starting a week’s work should be able to get hold of just a single project as in

cvs -d cvs_repository co naive-ticket-machine

or a whole week’s exercises as in

cvs -d cvs_repository co eg-140-week2


Here is my project structure:

+– week2
+– better-ticket-machine
+– src
+– test
+– bluej
+– files that students upload (a bluej project)


p>After some reading in Essential CVS and the CVS official manual I discovered how to use modules for this. Here is my module file:

Three different line formats are valid:

key -a aliases…

key [options] directory

key [options] directory files…

Where “options” are composed of:

-i prog Run “prog” on “cvs commit” from top-level of module.

-o prog Run “prog” on “cvs checkout” of module.

-e prog Run “prog” on “cvs export” of module.

-t prog Run “prog” on “cvs rtag” of module.

-u prog Run “prog” on “cvs update” of module.

-d dir Place module in directory “dir” instead of module name.

-l Top-level directory only — do not recurse.

NOTE: If you change any of the “Run” options above, you’ll have to

release and re-checkout any working directories of these modules.

And “directory” is a path to a directory relative to $CVSROOT.

The “-a” option specifies an alias. An alias is interpreted as if

everything on the right of the “-a” had been typed on the command line.

You can encode a module within a module by using the special ‘&’

character to interpose another module into the current module. This

can be useful for creating a module that consists of many directories

spread out over the entire source repository.


The modules file itself

modules CVSROOT modules

EG-140 Laboratory: only available to staff!

eg-140-laboratory eg-140-laboratory

Student projects: incomplete projects that have to be edited

Essentially the BlueJ projects provided with Barnes and Koelling

Week 2: the individual projects

better-ticket-machine eg-140-laboratory/week2/better-ticket-machine/bluej
naive-ticket-machine eg-140-laboratory/week2/naive-ticket-machine/bluej
book-exercise eg-140-laboratory/week2/book-exercise/bluej

Week 2: all together

eg-140-week2 -d week2 &naive-ticket-machine &better-ticket-machine &book-exercise

As you can see, we set up the bluej folder in each sub-project to be a module, named as
they are in Barnes and Kölling. We then have a combined module to bring together all the projects in a week’s labs (corresponding to a chapter in the book) as a CVS module eg-140-week2. When we check out this project, it creates a CVS sandbox named week2 which contains the three projects.


p>The next extension will be to get the staff-only version with worked solutions and JUnit tests working.


p>A couple of questions for later

  • If we want students to check-in changes to their own repository, how can we do it? The CVSROOT where the original code comes from would be inappropriate … effectively want each student to have his/own repository. CVS can probably do this so back to the book!
  • How can I get the compiled tests into the bluej folders without breaking version dependencies?

Author: cpjobling

Senior lecturer, College of Engineering, Swansea University