Handle column names with non-identifier characters

[Jollywatt]

Column names with non-standard characters don't seem to always be handled correctly:

# works
mtcars %>% dtplyr::lazy_dt() %>% mutate(`a.b` = 2) %>% group_by(`a.b`) %>% count()

# breaks
mtcars %>% dtplyr::lazy_dt() %>% mutate(`a b` = 2) %>% group_by(`a b`) %>% count()
#> Error in eval(bysub, x, parent.frame()) : object '`a b`' not found

Using package versions

dtplyr 1.3.1
data.table 1.14.8
dplyr 1.1.0

...on platform with version:

platform       x86_64-redhat-linux-gnu     
arch           x86_64                      
os             linux-gnu                   
system         x86_64, linux-gnu           
status                                     
major          3                           
minor          6.0                         
year           2019                        
month          04                          
day            26                          
svn rev        76424                       
language       R                           
version.string R version 3.6.0 (2019-04-26)
nickname       Planting of a Tree  

Thanks for your time

[markfairbanks]

All set, thanks for catching this!

# pak::pak("tidyverse/dtplyr")
library(dtplyr)
library(dplyr, warn.conflicts = FALSE)

x <- 3

dt <- lazy_dt(tibble(`a a` = rep("a", 3)))

dt %>%
  group_by(`a a`) %>%
  count()
#> Source: local data table [1 x 2]
#> Groups: a a
#> Call:   `_DT1`[, .(n = .N), keyby = .(`a a`)]
#> 
#>   `a a`     n
#>   <chr> <int>
#> 1 a         3
#> 
#> # Use as.data.table()/as.data.frame()/as_tibble() to access results