packrat isn't recognising installed package (purrr specifically)

was trying to install purrr, however I think unbeknownst to me it had been installed as a dependency of a previous package, so I got this result

> install.packages("purrr")
Installing package into ‘C:/Users/%MYDIRECTORYHERE%/packrat/lib/x86_64-w64-mingw32/3.6.0’
(as ‘lib’ is unspecified)
trying URL 'https://mirror.las.iastate.edu/CRAN/bin/windows/contrib/3.6/purrr_0.3.2.zip'
Content type 'application/zip' length 421290 bytes (411 KB)
downloaded 411 KB

package ‘purrr’ successfully unpacked and MD5 sums checked
Warning in install.packages :
  cannot remove prior installation of package ‘purrr’

The downloaded binary packages are in
	C:\Users\CURE\AppData\Local\Temp\RtmpoppOiT\downloaded_packages

now in the packrat directory there is a purrr folder with package files but in the packages tab of rstudio it shows this

status gives this error

> packrat::status()
Error in if (pkg$name == pkgName) return(pkg) : 
  argument is of length zero
In addition: Warning message:
In FUN(X[[i]], ...) : No DESCRIPTION file for installed package 'purrr'

snapshot gives this error

> packrat::snapshot()
Error: Unable to retrieve package records for the following packages:
- "purrr"

trying to remove the package gives this error

> remove.packages("purrr")
Removing package from ‘C:/Users/CURE/Documents/code/r/spring-2019-survey-2/packrat/lib/x86_64-w64-mingw32/3.6.0’
(as ‘lib’ is unspecified)
Error in remove.packages : there is no package called ‘purrr’

(but again it is there in the specified location)

library gives this error

> library("purrr")
Error in library("purrr") : there is no package called ‘purrr’

however the package and functions are accessible by calling with the full package name

> purrr::map(1:4, ~ . + 2)
[[1]]
[1] 3

[[2]]
[1] 4

[[3]]
[1] 5

[[4]]
[1] 6

I'm using RStudio 1.2.1335, R version 3.6.0, packrat 0.5.0, Windows 10 version 1809 - all R-related things were installed yeserday on a greenfield project and I had just updated windows so im running pretty much the latest version of everything

Start by reproducing the Windows setup with R 3.6.0 and packrat 0.5.0, installing purrr and running packrat::status() and packrat::snapshot(). Trace how the package is discovered in the packrat library and how its DESCRIPTION file is read; done means an installed purrr package is recognized without the reported errors.