Coalesce join function applied to data frame (expand coalesce function from dplyr)

coalesce_join.R

# For detailed explaination of this function, check this blog post: https://asterhu.com/post/2023-05-11-coalesce-join-in-r/
# Reference: https://alistaire.rbind.io/blog/coalescing-joins/
require(dplyr)
require(stringr)

coalesce_join <- function(x, y, 
                          by = NULL, 
                          keep = c("left", "right"), # "left" means keep value from left table if there's any duplicate value in both tables.
                          suffix = c(".x", ".y"), 
                          join = c("full_join","left_join", "right_join", "inner_join")) {
  keep = match.arg(keep)
  join = match.arg(join)
  join = match.fun(join)
  
  if (keep == "left") suffix_ = suffix else suffix_ = rev(suffix)
  
  join(x, y, by = by, suffix = suffix) %>% 
    mutate(
      across(ends_with(suffix_[1]), 
             ~coalesce(.,
                       get(str_replace(cur_column(), suffix_[1], suffix_[2]))
             ),
             .names = "{str_remove(.col, suffix_[1])}"
      ),
      .keep = "unused")
}