Feature request: return error when errant column used in distinct()

[RickPack]

Can dplyr error out when one identifies a variable that does not exist in the data frame?

## No error returned despite aa not appearing in the complimentary R data frame named "cars"
df <- cars %>% distinct(aa)

[holgerbrandl]

Still broken in dplyr_0.7.2. Was it moved to a later release?

[foo-bar-baz-qux]

@holgerbrandl yes, the change appears to be reverted and moved to v0.9 (probably)