Import module with non-standard file name

[Ben Finney]

"John Machin" <sjmachin at lexicon.net> writes:

> Ben Finney wrote:
> > Now that I've got it written as a Python module, I'd like to write
> > unit tests for that module, which of course will need to import
> > the program module to test it. The unit test can explicitly add
> > the directory where the program module lives to 'sys.path' for the
> > purpose of importing that module.
> 
> If it can do that, it can copy the MUT to some temp directory,
> adding .py to the end of the name of the new file, and put the temp
> directory in sys.path .... can't it?

Sounds like a nasty hack (not that fiddling sys.path isn't a hack, but
at least that one's addressed in Python 2.5 with relative and absolute
imports).

The problem with importing the program module from a file in a
different directory is that the program won't be able to find its own
relative modules. That leads to either *more* sys.path hackery, or
importing from a temporary file in the *same* directory.

Besides which, that's still two file names for the same module
code. The whole point of testing is to know that I'm testing the same
module; with a two-file shim, that's one step further away from that
ideal.

What you describe is possible, but leads to very smelly hacks. I'd
like to see what other options there are.

-- 
 \            "It's not what you pay a man, but what he costs you that |
  `\                                          counts."  -- Will Rogers |
_o__)                                                                  |
Ben Finney