Re: How might we mark a test suite isn't parallalizable?

On Thu, May 02, 2013 at 02:39:13PM -0500, brian d foy wrote:
> In HARNESS_OPTIONS we can set -jN to note we want parallel tests
> running, but how can a particular module, which might be buried in the
> dependency chain, tell the harness it can't do that?

When can a test not be parallelizable? Most of the examples that I can
think of (depending on a file resource, etc) smell like a design failure.
Tests should usually be able to use a unique temp file, etc.

> It seems to me that by the time the tests are running, it's too late
> because they are already in parallel and the best we can do is issue a
> warning or decide to fail.

Is it too late if the test itself declares "I cannot be parallelized"? If
not, then this declaration could be worked into Test::DescribeMe and
friends.