flatten_df to flatten embedded data object before binding

[dsen6644]

Embedded data fields to be individual columns rather than single list-column. This is more consistent with the mailing list export using the Qualtrics UI.

[juliasilge]

The unit testing for fetch_mailinglist() also needs to be updated.

I don't think we need to mess with the test fixture, only the test itself. You should be able to use either the test fixture or one of your own mailing lists to edit the test to match this new change.

[juliasilge]

Also, I think something isn't working right now with the new code. Here is what happens when I call it on a real mailing list:

library(qualtRics)

all_mailinglists()
#> # A tibble: 2 x 5
#>   libraryId        id              name                   category  folder      
#>   <chr>            <chr>           <chr>                  <chr>     <chr>       
#> 1 UR_8wfG5qsMxuh0… ML_3kszNEnMWzZ… Best sourdough bread … Unassign… /Uncategori…
#> 2 UR_8wfG5qsMxuh0… ML_6xLATuSWeOc… Cats I have known and… Unassign… /Uncategori…
fetch_mailinglist("ML_3kszNEnMWzZA1gN")
#> Error: Argument 1 must have names.
#> Backtrace:
#>     █
#>  1. └─qualtRics::fetch_mailinglist("ML_3kszNEnMWzZA1gN")
#>  2.   ├─dplyr::bind_cols(...) /qualtRics/R/fetch_mailinglist.R:49:2
#>  3.   │ └─rlang::list2(...)
#>  4.   └─purrr::flatten_df(...)
#>  5.     └─dplyr::bind_rows(res, .id = .id)

^{Created on 2020-06-10 by the reprex package (v0.3.0.9001)}

Here is what happens with the version currently in master:

library(qualtRics)

all_mailinglists()
#> # A tibble: 2 x 5
#>   libraryId        id              name                   category  folder      
#>   <chr>            <chr>           <chr>                  <chr>     <chr>       
#> 1 UR_8wfG5qsMxuh0… ML_3kszNEnMWzZ… Best sourdough bread … Unassign… /Uncategori…
#> 2 UR_8wfG5qsMxuh0… ML_6xLATuSWeOc… Cats I have known and… Unassign… /Uncategori…
fetch_mailinglist("ML_3kszNEnMWzZA1gN")
#> # A tibble: 6 x 8
#>   id    firstName lastName email externalDataRef… language unsubscribed
#>   <chr> <chr>     <chr>    <chr> <chr>            <chr>    <lgl>       
#> 1 MLRP… Mary      Smith    webt… <NA>             null     FALSE       
#> 2 MLRP… Barbara   Thomas   tris… <NA>             null     FALSE       
#> 3 MLRP… Thomas    Babbs    bave… <NA>             null     FALSE       
#> 4 MLRP… Nancy     Nanson   mslo… <NA>             null     FALSE       
#> 5 MLRP… Steven    Stevens  bmor… <NA>             null     FALSE       
#> 6 MLRP… Ashley    Ashson   bowm… <NA>             null     FALSE       
#> # … with 1 more variable: embeddedData <list>

^{Created on 2020-06-10 by the reprex package (v0.3.0.9001)}

[dsen6644]

@juliasilge how about this instead? Only attempts to flatten/bind embedded data when there is embedded data present.

[juliasilge]

Looks great! 🚀