do not match.fun as.integer64, pull 'factor' cond from cast_with_atts…

… to coerce_col

R/bmerge.R

@@ -11,8 +11,7 @@ mergeType = function(x) {
 
 cast_with_atts = function(x, as.f) {
   ans = as.f(x)
-  # do not copy attributes when coercing factor (to character)
-  if (!is.factor(x) && !is.null(attributes(x))) attributes(ans) = attributes(x)
+  if (!is.null(attributes(x))) attributes(ans) = attributes(x)
   ans
 }
 
@@ -21,7 +20,9 @@ coerce_col = function(dt, col, from_type, to_type, from_name, to_name, from_deta
     "Coercing %s column %s%s to type %s to match type of %s%s.\n",
     from_type, from_name, from_detail, to_type, to_name, to_detail
   )
-  set(dt, j=col, value=cast_with_atts(dt[[col]], match.fun(paste0("as.", to_type))))
+  as.f = switch(to_type, integer64 = bit64::as.integer64, match.fun(paste0("as.", to_type))) 
+  # do not copy attributes when coercing factor (to character)
+  set(dt, j=col, value = if (is.factor(dt[[col]])) as.f(dt[[col]]) else cast_with_atts(dt[[col]], as.f))
 }
 
 bmerge = function(i, x, icols, xcols, roll, rollends, nomatch, mult, ops, verbose)