pmap variants not handling .l properly

[jimjam-slam]

It seems like the map variants are mishandling .l somehow. The following error suggests that purrr::pmap() is trying to iterate over .l, rather than iterate down the elements of .l in parallel:

Column newcol must be length 32 (the number of rows) or one, not 3

library(tidyverse)
library(collateral)

test <- mtcars %>% as_tibble()
test
#> # A tibble: 32 x 11
#>      mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear  carb
#>    <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#>  1  21       6  160    110  3.9   2.62  16.5     0     1     4     4
#>  2  21       6  160    110  3.9   2.88  17.0     0     1     4     4
#>  3  22.8     4  108     93  3.85  2.32  18.6     1     1     4     1
#>  4  21.4     6  258    110  3.08  3.22  19.4     1     0     3     1
#>  5  18.7     8  360    175  3.15  3.44  17.0     0     0     3     2
#>  6  18.1     6  225    105  2.76  3.46  20.2     1     0     3     1
#>  7  14.3     8  360    245  3.21  3.57  15.8     0     0     3     4
#>  8  24.4     4  147.    62  3.69  3.19  20       1     0     4     2
#>  9  22.8     4  141.    95  3.92  3.15  22.9     1     0     4     2
#> 10  19.2     6  168.   123  3.92  3.44  18.3     1     0     4     4
#> # ... with 22 more rows

# native pmap works fine
test %>% mutate(
  newcol = pmap(
    select(., vs, am, gear),
    function(vs, am , gear) { vs + am + gear } ))
#> # A tibble: 32 x 12
#>      mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear  carb newcol
#>    <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <list>
#>  1  21       6  160    110  3.9   2.62  16.5     0     1     4     4 <dbl ~
#>  2  21       6  160    110  3.9   2.88  17.0     0     1     4     4 <dbl ~
#>  3  22.8     4  108     93  3.85  2.32  18.6     1     1     4     1 <dbl ~
#>  4  21.4     6  258    110  3.08  3.22  19.4     1     0     3     1 <dbl ~
#>  5  18.7     8  360    175  3.15  3.44  17.0     0     0     3     2 <dbl ~
#>  6  18.1     6  225    105  2.76  3.46  20.2     1     0     3     1 <dbl ~
#>  7  14.3     8  360    245  3.21  3.57  15.8     0     0     3     4 <dbl ~
#>  8  24.4     4  147.    62  3.69  3.19  20       1     0     4     2 <dbl ~
#>  9  22.8     4  141.    95  3.92  3.15  22.9     1     0     4     2 <dbl ~
#> 10  19.2     6  168.   123  3.92  3.44  18.3     1     0     4     4 <dbl ~
#> # ... with 22 more rows
test %>% mutate(
  newcol = pmap_dbl(
    select(., vs, am, gear),
    function(vs, am , gear) { vs + am + gear } ))
#> # A tibble: 32 x 12
#>      mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear  carb newcol
#>    <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>  <dbl>
#>  1  21       6  160    110  3.9   2.62  16.5     0     1     4     4      5
#>  2  21       6  160    110  3.9   2.88  17.0     0     1     4     4      5
#>  3  22.8     4  108     93  3.85  2.32  18.6     1     1     4     1      6
#>  4  21.4     6  258    110  3.08  3.22  19.4     1     0     3     1      4
#>  5  18.7     8  360    175  3.15  3.44  17.0     0     0     3     2      3
#>  6  18.1     6  225    105  2.76  3.46  20.2     1     0     3     1      4
#>  7  14.3     8  360    245  3.21  3.57  15.8     0     0     3     4      3
#>  8  24.4     4  147.    62  3.69  3.19  20       1     0     4     2      5
#>  9  22.8     4  141.    95  3.92  3.15  22.9     1     0     4     2      5
#> 10  19.2     6  168.   123  3.92  3.44  18.3     1     0     4     4      5
#> # ... with 22 more rows

# collateral variants do not
test %>% mutate(
  newcol = pmap_safely(
    select(., vs, am, gear),
    function(vs, am , gear) { vs + am + gear } ))
#> Error: Column `newcol` must be length 32 (the number of rows) or one, not 3
test %>% mutate(
  newcol = pmap_quietly(
    select(., vs, am, gear),
    function(vs, am , gear) { vs + am + gear } ))
#> Error in .f(...): argument "am" is missing, with no default
test %>% mutate(
  newcol = pmap_peacefully(
    select(., vs, am, gear),
    function(vs, am , gear) { vs + am + gear } ))
#> Error: Column `newcol` must be length 32 (the number of rows) or one, not 3

^{Created on 2019-07-08 by the reprex package (v0.3.0)}

[jimjam-slam]

More tests:

library(purrr)
library(collateral)

list1 = 1:5
list2 = c('red', 'blue', 'yellow', 'green', 'purple')
list3 = 6:10
all_lists = list(list1, list2, list3)

# classic pmap or pmap_chr works regardless of how function is specified

pmap(all_lists, function(list1, list2, list3) { paste(list1, list2, list3) })
#> [[1]]
#> [1] "1 red 6"
#> 
#> [[2]]
#> [1] "2 blue 7"
#> 
#> [[3]]
#> [1] "3 yellow 8"
#> 
#> [[4]]
#> [1] "4 green 9"
#> 
#> [[5]]
#> [1] "5 purple 10"
pmap(all_lists, ~ paste(..1, ..2, ..3))
#> [[1]]
#> [1] "1 red 6"
#> 
#> [[2]]
#> [1] "2 blue 7"
#> 
#> [[3]]
#> [1] "3 yellow 8"
#> 
#> [[4]]
#> [1] "4 green 9"
#> 
#> [[5]]
#> [1] "5 purple 10"
pmap_chr(all_lists, ~ paste(..1, ..2, ..3))
#> [1] "1 red 6"     "2 blue 7"    "3 yellow 8"  "4 green 9"   "5 purple 10"

# collateral variants do not, although they handle the errors themselves
# in this case

safe_test <- pmap_safely(all_lists, ~ paste(..1, ..2, ..3))
quiet_test <- pmap_quietly(all_lists, ~ paste(..1, ..2, ..3))
#> Error in paste(..1, ..2, ..3): the ... list contains fewer than 2 elements
peaceful_test <- pmap_peacefully(all_lists, ~ paste(..1, ..2, ..3))

safe_test
#> _ E
#> _ E
#> _ E
str(safe_test)
#> List of 3
#>  $ :List of 2
#>   ..$ result: NULL
#>   ..$ error :List of 2
#>   .. ..$ message: chr "the ... list contains fewer than 2 elements"
#>   .. ..$ call   : language paste(..1, ..2, ..3)
#>   .. ..- attr(*, "class")= chr [1:3] "simpleError" "error" "condition"
#>  $ :List of 2
#>   ..$ result: NULL
#>   ..$ error :List of 2
#>   .. ..$ message: chr "the ... list contains fewer than 2 elements"
#>   .. ..$ call   : language paste(..1, ..2, ..3)
#>   .. ..- attr(*, "class")= chr [1:3] "simpleError" "error" "condition"
#>  $ :List of 2
#>   ..$ result: NULL
#>   ..$ error :List of 2
#>   .. ..$ message: chr "the ... list contains fewer than 2 elements"
#>   .. ..$ call   : language paste(..1, ..2, ..3)
#>   .. ..- attr(*, "class")= chr [1:3] "simpleError" "error" "condition"
#>  - attr(*, "class")= chr [1:2] "safely_mapped" "list"

quiet_test
#> Error in eval(expr, envir, enclos): object 'quiet_test' not found
str(quiet_test)
#> Error in str(quiet_test): object 'quiet_test' not found

peaceful_test
#> _ O _ _ E
#> _ O _ _ E
#> _ O _ _ E
str(peaceful_test)
#> List of 3
#>  $ :List of 5
#>   ..$ result  : NULL
#>   ..$ output  : chr ""
#>   ..$ warnings: chr(0) 
#>   ..$ messages: chr(0) 
#>   ..$ error   :List of 2
#>   .. ..$ message: chr "the ... list contains fewer than 2 elements"
#>   .. ..$ call   : language paste(..1, ..2, ..3)
#>   .. ..- attr(*, "class")= chr [1:3] "simpleError" "error" "condition"
#>  $ :List of 5
#>   ..$ result  : NULL
#>   ..$ output  : chr ""
#>   ..$ warnings: chr(0) 
#>   ..$ messages: chr(0) 
#>   ..$ error   :List of 2
#>   .. ..$ message: chr "the ... list contains fewer than 2 elements"
#>   .. ..$ call   : language paste(..1, ..2, ..3)
#>   .. ..- attr(*, "class")= chr [1:3] "simpleError" "error" "condition"
#>  $ :List of 5
#>   ..$ result  : NULL
#>   ..$ output  : chr ""
#>   ..$ warnings: chr(0) 
#>   ..$ messages: chr(0) 
#>   ..$ error   :List of 2
#>   .. ..$ message: chr "the ... list contains fewer than 2 elements"
#>   .. ..$ call   : language paste(..1, ..2, ..3)
#>   .. ..- attr(*, "class")= chr [1:3] "simpleError" "error" "condition"
#>  - attr(*, "class")= chr [1:2] "peacefully_mapped" "list"

^{Created on 2019-07-08 by the reprex package (v0.3.0)}

[jimjam-slam]

Think I've caught it: the pmap_*() functions were hooked up to map_wrapper(), rather than pmap_wrapper(). Implementing fix now.

[jimjam-slam]

Fixed in dev 🎊