Fix data frame initialisation in bind_rows()

Closes tidyverse#5417
Closes tidyverse#5749

NEWS.md

@@ -79,6 +79,9 @@
 * `mutate()` always keeps grouping variables, unconditional to `.keep=` (#5582).
 
 * dplyr now depends on R 3.3.0
+* Fixed issue in `bind_rows()` causing lists to be incorrectly transformed as
+  data frames (#5417).
+
 
 # dplyr 1.0.2
 

R/bind.r

@@ -128,7 +128,7 @@ bind_rows <- function(..., .id = NULL) {
   first <- dots[[1L]]
   dots <- map(dots, function(.x) {
     if (vec_is_list(.x)) {
-      .x <- new_data_frame(as.list(.x))
+      .x <- vctrs::data_frame(!!!.x)
     }
     .x
   })

tests/testthat/test-bind.R

@@ -550,6 +550,18 @@ test_that("bind_rows() correctly restores (#2457)", {
   expect_s3_class(df$x, "vctrs_list_of")
 })
 
+test_that("bind_rows() validates lists (#5417)", {
+  out <- bind_rows(list(x = 1), list(x = 1, y = 1:2))
+  expect_identical(out, tibble(x = c(1, 1, 1), y = c(NA, 1:2)))
+
+  x <- vctrs::list_of(a = data.frame(x = 1), b = data.frame(y = 2:3))
+  out <- bind_rows(x)
+  exp <- tibble(
+    a = vctrs::data_frame(x = c(1, 1), y = int(NA, NA)),
+    b = vctrs::data_frame(x = dbl(NA, NA), y = 2:3)
+  )
+  expect_identical(out, exp)
+})
 
 # Errors ------------------------------------------------------------------