Date column coerced from "date" -> "dttm" when xts converts back to tibble.

[DavisVaughan]

When using a tq_mutate() and a function like periodReturn, the date column is coerced from a date to a dttm (POSIXct) class. Minor quirk, but hopefully is fixable.

From our email:
"The date class change is what happens during the conversion process from tibble to xts and then back to tibble. When xts goes back to tibble the date is POSIXct by default."

Reproducible example created using jennybc's reprex package:

library(tidyquant)
apple <- tq_get("AAPL")
apple %>% tq_transform(Ad, transform_fun = periodReturn, period = "monthly", col_rename = "monthly_ret")
#> # A tibble: 121 × 2
#>          date  monthly_ret
#>        <dttm>        <dbl>
#> 1  2007-01-31  0.023031022
#> 2  2007-02-28 -0.013064288
#> 3  2007-03-30  0.098097108
#> 4  2007-04-30  0.074157832
#> 5  2007-05-31  0.214328672
#> 6  2007-06-29  0.007013839
#> 7  2007-07-31  0.079645970
#> 8  2007-08-31  0.051001827
#> 9  2007-09-28  0.108246690
#> 10 2007-10-31  0.237701136
#> # ... with 111 more rows

[mdancho84]

Fix implemented. Switched ymd() function to as_date(), which seems to do the trick. Please test it, and let me know if it works as planned.

[DavisVaughan]

Great! That seems to have worked. Nice, easy fix.