handle input df to get_dupes() that already has a variable called n

fixes #162

NEWS.md

@@ -37,6 +37,7 @@ The legacy functions `crosstab` and `adorn_crosstab` have been deprecated, but r
 
 ## Bug fixes
 * `adorn_totals("row")` handles quirky variable names in 1st column [(#118)](https://github.com/sfirke/janitor/issues/118)
+* `get_dupes()` returns the correct result when a variable in the input data.frame is already called `"n"` [(#162)](https://github.com/sfirke/janitor/issues/162)
 
 
 # janitor 0.3.1  (Release date: 2018-01-04)

R/get_dupes.R

@@ -14,38 +14,37 @@
 #'
 
 get_dupes <- function(dat, ...) {
-  names <- as.list(substitute(list(...)))[-1L]
+  uq_names <- as.list(substitute(list(...)))[-1L] # unquoted names for NSE calls, need quoted names separately for messages + warnings
   df_name <- deparse(substitute(dat))
 
   # check that each variable name provided is present in names(dat); if not, throw error
-  var_names <- names
-  if(is.list(var_names)){ var_names <- lapply(names, deparse) } # 'names' is not a list if defaulting to whole df, need this for consistency
-  check_vars_in_df(dat, df_name, unlist(var_names))
+  q_names <- uq_names
+  if(is.list(q_names)){ q_names <- lapply(uq_names, deparse) } # 'names' is not a list if defaulting to whole df, need this for consistency
+  check_vars_in_df(dat, df_name, unlist(q_names))
   dupe_count <- NULL # to appease NOTE for CRAN; does nothing.
 
-  if(length(names)==0){ # if called on an entire data.frame with no specified variable names
-    var_names <- names(dat)
-    names <- paste0("`", as.list(names(dat)), "`") # to handle illegal variable names 
+  if(length(uq_names)==0){ # if called on an entire data.frame with no specified variable names
+    q_names <- names(dat)
+    uq_names <- paste0("`", as.list(names(dat)), "`") # to handle illegal variable names 
     message("No variable names specified - using all columns.\n")
   }
 
   # calculate counts to join back to main df
   counts <- dat %>%
-    dplyr::count_(vars = names)
-
+    dplyr::count_(vars = uq_names)
 
+  names(counts)[ncol(counts)] <- "dupe_count"
   # join new count vector to main data.frame
   dupes <- suppressMessages(dplyr::inner_join(counts, dat))
 
   dupes <- dupes %>%
-    dplyr::filter(n > 1) %>%
+    dplyr::filter(dupe_count > 1) %>%
     dplyr::ungroup() %>%
-    dplyr::arrange_(.dots = names) %>%
-    dplyr::rename(dupe_count = n)
+    dplyr::arrange_(.dots = uq_names)
 
   # shorten error message for large data.frames
-  if(length(var_names) > 10){ var_names <- c(var_names[1:9], paste("... and", length(var_names) - 9, "other variables")) }
-  if(nrow(dupes) == 0){message(paste0("No duplicate combinations found of: ", paste(var_names, collapse = ", ")))}
+  if(length(q_names) > 10){ q_names <- c(q_names[1:9], paste("... and", length(q_names) - 9, "other variables")) }
+  if(nrow(dupes) == 0){message(paste0("No duplicate combinations found of: ", paste(q_names, collapse = ", ")))}
   dupes
 }