Feature has context

[machow]

address issue #187. Implements a function has_context, which checks the names of iterator/context variables. Uses single dispatch to do customized tests if called from a node directly (e.g. check_with(0).has_context()).

[filipsch]

Looks good.
You're not simplifying the test_with() function?

[machow]

It's in test_with here: https://github.com/datacamp/pythonwhat/pull/198/files#diff-63ad8ae79e64138d3954353b96d0f9a9L54

[filipsch]

Okay but you're not leaving out the too_many part, that is the 'difference' between the test_with and the composed check_ functions. I remember we talked about making the 'mapping very clear', and this could mean cutting out some stuff here and there, based on whether some SCTs that are currently in production are using this.

[machow]

Ah, I see--I just now changed it to use the helper SCT has_equal_part_len (which was being used in the comprehension tests). We can expose it to SCT creators. I'm fine with a long name for it, but let me think about what to call it for a bit...