Reshape on multiple columns fails when args are passed as named lists

[sunbee]

Is it possible to reshape on multiple columns by passing a list of column names (value.var) along with a list of aggregation functions (fun.aggregate). This works well when those lists are explicitly passed to the function arguments. It appears to result in an error condition if the lists are passed as variables.

dt = data.table(x=sample(5,20,TRUE), y=sample(2,20,TRUE), 
                z=sample(letters[1:2], 20,TRUE), d1 = runif(20), d2=1L)
funs = list(sum, mean)
vars = list("d1", "d2")
dcast(dt, x + y ~ z, fun=funs, value.var=vars)

R version 3.5.0 (2018-04-23)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 7 x64 (build 7601) Service Pack 1
Matrix products: default

locale:
[1] LC_COLLATE=English_United States.1252 LC_CTYPE=English_United States.1252
[3] LC_MONETARY=English_United States.1252 LC_NUMERIC=C
[5] LC_TIME=English_United States.1252

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

other attached packages:
[1] testthat_2.0.0 data.table_1.11.4

loaded via a namespace (and not attached):
[1] compiler_3.5.0 magrittr_1.5 R6_2.2.2 tools_3.5.0 rlang_0.2.1

[MarkusBonsch]

Very strange. I figured it appears if fun is a predefined list, not so much on value.var.
Unfortunately rather low priority at the moment since there are bigger issues.

[arunsrinivasan]

Also acknowledge #1974 when done.