Graph.__getitem__ runtime type checking for slices breaks working code

[tgbugs]

The changes in
c37d399#diff-a8bea910ef28d48bce0a390d9ab24c55ac32f1c9a39d9cd215224e5447b70c83R709 break working code.

The type of the instance being passed does not matter in this context because the only thing that matters is whether or not the instance being passed is in the graph. Historically this means that code could pass strings, tuples, etc. to the slice and rdflib would find there were no triples containing that value and move along. This behavior is desirable (and correct) for a wide variety of dynamically typed code.

The recently added asserts can be placed behind an option to only enforce runtime type checking for those that want it in the same way that e.g. Graph.subject_objects does not force runtime asserts on consuming libraries. (In effect all the change does is force users to switch away from the convenient slice notation and to the more verbose Graph.subjects, ... Graph.predicate_objects functions.)

[ashleysommer]

Thanks @tgbugs
There was a release mistake, those typing/assert changes from main branch were not meant to be released in v7.1.2. This will be rectified in the upcoming v7.1.3 release.

You're right, these asserts should be put behind a if TYPE_CHECKING:, we will make that fix in main, so this regression does not make it into the v8.0 release.