added tests

Author: venom1204

R/data.table.R

@@ -1410,7 +1410,7 @@ replace_dot_alias = function(e) {
         if (is.function(jval)) {      
           stopf("RHS of `:=` is a function. To create a new column of functions, it must be a list column (e.g., wrap in `list()`).")
         } else if (is.list(jval) && length(jval) == 1 && is.function(jval[[1L]])) {
-          stopf("RHS of `:=` is a length-1 list containing a function. `data.table` does not automatically recycle lists. To create a list-column, use `rep(list(myfun), .N)` or `list(replicate(.N, myfun))` to match the number of rows.")
+          stopf("RHS of `:=` is a length-1 list containing a function. `data.table` does not automatically recycle lists. To create a list-column, use `rep(list(myfun), .N)` to match the number of rows.")
         }
       }
       # TODO?: use set() here now that it can add new columns. Then remove newnames and alloc logic above.

inst/tests/tests.Rraw

@@ -21157,3 +21157,8 @@ test(2317.6, DT1[DF1, on='a', .(d = x.a + i.d)]$d, 5)
 test(2317.7, DT1[DF2, on='a', e := i.e]$e, 5)
 test(2317.8, DT1[DF2, on='a', e2 := x.a + i.e]$e2, 6)
 test(2317.9, DT1[DF2, on='a', .(e = x.a + i.e)]$e, 6)
+
+DT = data.table(x = 1:3)
+
+test(2318.1, DT[, y := mean], error = "RHS of `:=` is a function")
+test(2318.2, DT[, y := list(mean)], error = "RHS of `:=` is a length-1 list containing a function")