BTreeMap navigation done safer & faster#68827

Merged

bors merged 3 commits intorust-lang:masterfrom

ssomers:btree_navigation_revisited

Feb 28, 2020

Commits on Feb 8, 2020

Refine and extend benchmarks of mutable BTreeSet methods
ssomers
committed

Commits on Feb 27, 2020

Fix and test implementation of BTreeMap's first_entry, last_entry, pop_first, pop_last
ssomers
committed

Commits on Feb 28, 2020

Make implementation of navigation simpler, safer and faster
ssomers
committed