After a bit of work, I just sent my first attempt to get diff working with a memory context. My basic idea was as follows:

  • make memctx inherit from workingctx so that it gets all the goodness of a regular context, like so
wpg_div_memctx1
  • add any minimal number of methods to memctx to make diff work

It was pretty straight-forward but as I wrote this series I learned a few things. For one thing, I should have split up the patch series into two series: one for add ipdb debugging and one for the memctx changes. Another potential pitfall (noticed in patch 12), is the discrepancy of memctx with its other siblings. memctx has a different __init__ signature which suggests that a bigger refactoring might be needed.

Finally, as Kevin pointed out, having memctx inherit from a workingctx seems a little forced. For example, isinstance(workingctx, obj) vs. isinstance(memctx, obj) doesn’t quite read the same way. I think the only way around this would be for total context.py refactoring as such,

wpg_div_memctx2

Off to my next round of patches!