Can't convert <character> to <integer> with names_ptypes

[abichat]

The example given in the vignette "Pivoting" with the use of names_ptypes argument is not reproducible with tidyr 1.0.2.

> library(tidyr)
> billboard %>% 
+   pivot_longer(
+     cols = starts_with("wk"), 
+     names_to = "week", 
+     names_prefix = "wk",
+     names_ptypes = list(week = integer()),
+     values_to = "rank",
+     values_drop_na = TRUE,
+   )
Erreur : Can't convert <character> to <integer>.
Run `rlang::last_error()` to see where the error occurred.
> sessionInfo()
R version 3.6.3 (2020-02-29)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS Mojave 10.14.6

Matrix products: default
BLAS:   /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/3.6/Resources/lib/libRlapack.dylib

locale:
[1] fr_FR.UTF-8/fr_FR.UTF-8/fr_FR.UTF-8/C/fr_FR.UTF-8/fr_FR.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] tidyr_1.0.2

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.4.8      packrat_0.5.0     crayon_1.3.4      dplyr_0.8.99.9002 R6_2.4.1          lifecycle_0.2.0  
 [7] magrittr_1.5      pillar_1.4.3      stringi_1.4.6     rlang_0.4.5.9000  rstudioapi_0.11   vctrs_0.2.99.9011
[13] generics_0.0.2    ellipsis_0.3.0    tools_3.6.3       glue_1.4.0        purrr_0.3.4       compiler_3.6.3   
[19] pkgconfig_2.0.3   tidyselect_1.0.0  tibble_3.0.1   

[hadley]

Duplicate of #921