feat: get dimensions of a csv data file without loading it

NAMESPACE

@@ -3,6 +3,7 @@
 export("%=%")
 export(.repath)
 export(close_view)
+export(get_file_info)
 export(get_git_branch)
 export(sa_branch_get)
 export(sa_branch_set)

R/get_file_info.R

@@ -0,0 +1,29 @@
+#' Get Column Names and Row Count
+#'
+#' This function returns the number of columns and the number of rows in a given file.
+#' It uses the `system` function to execute shell commands.
+#'
+#' @param filepath The path to the file.
+#' @param verbose If `TRUE`, message the number of columns and rows.
+#' @return A list with the number of columns and rows.
+#' @export
+get_file_info <- function(filepath, verbose = FALSE) {
+  # Get the first line of the file and split it into column names
+  column_names <- system(paste0('head -n 1 "', filepath, '"'), intern = TRUE)
+  num_cols <- length(unlist(strsplit(column_names, split = ';')))
+
+  # Get the number of lines in the file
+  row_number <- system(if (.Platform$OS.type == "windows") {
+    paste0('find /c /v "" "', filepath, '"')
+  } else {
+    paste0('wc -l "', filepath, '"')
+  }, intern = TRUE)
+  num_rows <- as.integer(sub(".*: ", "", row_number[2])) - 1
+
+  if (verbose) {
+    message(paste("number of columns:", num_cols))
+    message(paste("number of rows:", num_rows))
+  }
+
+  return(list(num_cols = num_cols, num_rows = num_rows))
+}