Separate_rows in v1.1.1 doesn't seem to work the same as in v1.1.0

[alexeyza]

There are inconsistencies in how separate_rows works in version 1.1.1 compared to version 1.1.0. I noticed it when my code that was working in 1.1.0 was now returning errors due to empty data.frames and other errors (in 1.1.1).

# reprex (version 1.1.0)

> iris %>% separate_rows(Species, sep = ";")
# A tibble: 150 x 5
   Sepal.Length Sepal.Width Petal.Length Petal.Width Species
          <dbl>       <dbl>        <dbl>       <dbl> <chr>  
 1          5.1         3.5          1.4         0.2 setosa 
 2          4.9         3            1.4         0.2 setosa 
 3          4.7         3.2          1.3         0.2 setosa 
 4          4.6         3.1          1.5         0.2 setosa 
 5          5           3.6          1.4         0.2 setosa 
 6          5.4         3.9          1.7         0.4 setosa 
 7          4.6         3.4          1.4         0.3 setosa 
 8          5           3.4          1.5         0.2 setosa 
 9          4.4         2.9          1.4         0.2 setosa 
10          4.9         3.1          1.5         0.1 setosa 
# … with 140 more rows

# reprex (version 1.1.1)

> iris %>% separate_rows(Species, sep = ";")
Error in .f(.x[[i]], ...) : non-character argument

Also, try both versions on a dataframe with a column of empty strings in it:

iris %>% mutate(test = "") %>% separate_rows(test, sep = ";")

In version 1.1.0 it returns the full original dataframe, while in version 1.1.1 it returns an empty dataframe.

---

From a quick glimpse on recent changes, I think it comes down to the following change:
f0bcfd9#diff-46dad93d5ee31264d672c8ed8c984258

I tried to see what could be the source for the difference by looking at:

> stringi::stri_split_regex(str="", pattern = ";")
[[1]]
[1] ""

> strsplit("", split = ";", perl = T)
[[1]]
character(0)