- Fixes bugs where concretization would fail due to an erroneously cached
_concrete attribute.
- Ripped out a bunch of code in spec.py that isn't needed/valid anymore:
- The various concrete() methods on different types of Specs would
attempt to statically compute whether the Spec was concrete.
- This dates back to when DAGs were simpler and there were no optional
dependencies. It's actually NOT possible to compute statically
whether a Spec is concrete now. The ONLY way you know is if it goes
through concretization and is marked concrete once that completes.
- This commit removes all simple concreteness checks and relies only on
the _concrete attribute. This should make thinking about
concreteness simpler.
- Fixed a couple places where Specs need to be marked concrete explicitly.
- Specs read from files and Specs that are destructively copied from
concrete Specs now need to be marked concrete explicitly.
- These spots may previously have "worked", but they were brittle and
should be explcitly marked anyway.