R/case_insensitive_joins.R

In marcusihsmarkit/BasicSettings:

#' This performs case insensitive joins of the joins in dplyr
#' https://gist.github.com/jimhester/a060323a05b40c6ada34
#' @examples
#' df <- insensitive.join(left_join)(df_x, df_y, by = list(x = c(), y = c()))
#' @export
insensitive.join <- function(fun = inner_join) {
  new_fun <- fun
  body(new_fun) <- substitute({
    by <- dplyr:::common_by(by, x, y)

    tmp_by_x <- paste0("_", by$x, "_")
    tmp_by_y <- paste0("_", by$y, "_")
    for (i in seq_along(by$x)) {
      x[[tmp_by_x[[i]]]] <- tolower(x[[by$x[[i]]]])
      y[[tmp_by_y[[i]]]] <- tolower(y[[by$y[[i]]]])
      y[[by$y[[i]]]] <- NULL
    }

    res <- fun(x, y, list(x = tmp_by_x, y = tmp_by_y))
    res[tmp_by_x] <- list(NULL)

    res
  })

  new_fun
}