[BUG] Concat duplicates errors (or lack there of)#38654

Merged

jreback merged 2 commits intopandas-dev:masterfrom

ivirshup:concat-duplicates

Dec 24, 2020

Commits on Dec 23, 2020

Revert "[BUG]: Fix ValueError in concat() when at least one Index has duplicates (#36290)"
ivirshup
committed
Better error message for concat with duplicate indices
ivirshup
committed