ENH: Implement _from_sequence_of_strings for BooleanArray
- [x] closes #31131
- [x] tests added / passed
- [x] passes `black pandas`
- [x] whatsnew entry
Hello @dsaxton! Thanks for updating this PR. We checked the lines you've touched for [PEP 8](https://www.python.org/dev/peps/pep-0008) issues, and found:







There are currently no PEP 8 issues detected in this Pull Request. Cheers! :beers: 

##### Comment last updated at 2020-01-23 17:13:40 UTC lgtm unless @jorisvandenbossche has more comments. (should make an issue to review performance of the string construction, e.g. an asv would asnwer if perf is an issue here) LGTM aside from https://github.com/pandas-dev/pandas/pull/31159/files/29dbfa1165311260ffd54afbc6f8208ee27405c6#diff-20faa368ac513e325ac07ec72a8f93c7 There are actually also options in read_csv to specify the true/false strings. I suppose we are OK to ignore that? Or can we pass that through somehow? I’m ok with ignoring that for now > Can you also check what you get when you have an invalid string in your column? (if it is a decent error message)

Right now the error message that gets raised is `TypeError: Need to pass bool-like values` from inside `BooleanArray._from_sequence`. I think this should be a `ValueError`, maybe raised from `map_string` (instead of returning any string that doesn't match one of the true / false ones)? >  I think this should be a ValueError, maybe raised from map_string (instead of returning any string that doesn't match one of the true / false ones)?

Yes, I think it is easy to raise a more informative ValueError from the last `else` clause in `map_string`