Removed dead intervaltree code

[WillAyd]

While looking to reduce build warnings I came across these methods and couldn't find any public use to them. The only one that seems to get hit is get_loc and that is in tests only so I think dead code

[jbrockmendel]

It looks like IntervalIndex.get_loc doesn't use self._engine.get_loc, which seems kind of weird. Also looks like there's a good bit of either untested or dead code in indexes.interval: https://codecov.io/gh/pandas-dev/pandas/src/master/pandas/core/indexes/interval.py

[WillAyd]

@jschendel

[jreback]

lgtm. @jschendel if you'd have a look and merge if ok.

[jschendel]

It looks like IntervalIndex.get_loc doesn't use self._engine.get_loc, which seems kind of weird.

This is a result of the interval indexing behavior changes where we no longer allow partial interval overlaps, which was the main purpose of IntervalTree.get_loc. The logic is now a bit simpler and much more straightforward to vectorize in numpy.

Also looks like there's a good bit of either untested or dead code in indexes.interval

Yes, some of these can be removed for the same reason as above. However, others are simply helper functions that are poorly tested. After a quick glance:

• _get_next_label is used but poorly tested
• _get_interval_closed_bounds can be removed
• _maybe_cast_indexed can be removed
• _can_reindex is used and overrides a parent class definition that's not valid for IntervalIndex
• _find_non_overlapping_monotonic_bounds can be removed

Can look into the above more next week.

[jschendel]

Thanks @WillAyd!