Lines read and skip lines use different evaluation in vroom_lines

[pepijn-devries]

Originally reported here at readr:

tidyverse/readr#1500

After some more digging I have traced this issue back to vroom where the same problem occurs when skipping lines when there is a Line Feed (\n) followed by a Carriage Return (\r). In the reprex below skipping 2 lines results in unexpected behaviour, I think it is skipping the lines, but then stops reading the remainder. If you skip 3 lines, all seems well again:

library(vroom)

text <- "001\n002\n\r003\n004"

vroom_lines(I(text), skip = 0)
#> [1] "001"   "002"   "\r003" "004"
vroom_lines(I(text), skip = 1)
#> [1] "002"   "\r003" "004"
vroom_lines(I(text), skip = 2)
#> [1] ""
vroom_lines(I(text), skip = 3)
#> [1] "003" "004"
vroom_lines(I(text), skip = 4)
#> [1] "004"

^{Created on 2025-03-02 with reprex v2.0.2}