Revert "Fix mapping to data frames with functions returning vectors" (#…

…398)

NEWS.md

@@ -1,9 +1,6 @@
 
 # purrr 0.2.3.9000
 
-* `map_dfr()` and `map_dfc()` now handle functions returning vectors
-  correctly (#179).
-
 
 # purrr 0.2.3
 

R/map.R

@@ -166,7 +166,7 @@ map_dfr <- function(.x, .f, ..., .id = NULL) {
 
   .f <- as_mapper(.f, ...)
   res <- map(.x, .f, ...)
-  dplyr::bind_rows(!!! res, .id = .id)
+  dplyr::bind_rows(res, .id = .id)
 }
 
 #' @rdname map
@@ -183,7 +183,7 @@ map_dfc <- function(.x, .f, ...) {
 
   .f <- as_mapper(.f, ...)
   res <- map(.x, .f, ...)
-  dplyr::bind_cols(!!! res)
+  dplyr::bind_cols(res)
 }
 
 #' @export

tests/testthat/test-map.R

@@ -53,6 +53,15 @@ test_that("map forces arguments in same way as base R", {
   expect_equal(f_map[[2]](0), f_base[[2]](0))
 })
 
+test_that("row and column binding work", {
+  mtcar_mod <- mtcars %>%
+    split(.$cyl) %>%
+    map(~ lm(mpg ~ wt, data = .x))
+  f_coef <- function(x) as.data.frame(t(as.matrix(coef(x))))
+  expect_length(mtcar_mod %>% map_dfr(f_coef), 2)
+  expect_length(mtcar_mod %>% map_dfc(f_coef), 6)
+})
+
 test_that("walk is used for side-effects", {
   expect_output(walk(1:3, str))
 })
@@ -62,24 +71,3 @@ test_that("map_if() and map_at() always return a list", {
   expect_identical(map_if(df, is.character, ~"out"), list(x = 1, y = "out"))
   expect_identical(map_at(df, 1, ~"out"), list(x = "out", y = "a"))
 })
-
-test_that("map_dfr() and map_dfc() handle data frames", {
-  tbl <- tibble::tibble(x = 1, y = 2)
-  expect_identical(map_dfr(1:2, ~tbl), dplyr::bind_rows(tbl, tbl))
-  expect_identical(map_dfc(1:2, ~tbl), dplyr::bind_cols(tbl, tbl))
-})
-
-test_that("map_dfr() and map_dfc() handle dataframeable lists", {
-  tbl <- tibble::tibble(x = 1, y = 2)
-  list <- list(x = 1, y = 2)
-  expect_identical(map_dfr(1:2, ~list), dplyr::bind_rows(tbl, tbl))
-  expect_identical(map_dfc(1:2, ~list), dplyr::bind_cols(tbl, tbl))
-})
-
-test_that("map_dfr() and map_dfc() handle named vectors", {
-  row <- c(x = 1, y = 2)
-  expect_identical(map_dfr(1:2, ~row), tibble::tibble(x = c(1, 1), y = c(2, 2)))
-
-  col <- c(1, 2)
-  expect_identical(map_dfc(c(w = 0, z = 0), ~col), tibble::tibble(w = col, z = col))
-})