corrected last test

Author: Mukulyadav2004

R/as.data.table.R

@@ -214,7 +214,7 @@ as.data.table.list = function(x,
 }
 
 as.data.table.data.frame = function(x, keep.rownames=FALSE, key=NULL, ...) {
-  if (is.data.table(x)) return(as.data.table.data.table(x)) # S3 is weird, #6739. Also # nocov; this is tested in 2302.{2,3}, not sure why it doesn't show up in coverage.
+  if (is.data.table(x)) return(as.data.table.data.table(x, key=key)) # S3 is weird, #6739. Also # nocov; this is tested in 2302.{2,3}, not sure why it doesn't show up in coverage.
   if (!identical(class(x), "data.frame")) return(as.data.table(as.data.frame(x), keep.rownames=keep.rownames, key=key, ...))
   if (!isFALSE(keep.rownames)) {
     # can specify col name to keep.rownames, #575; if it's the same as key,
@@ -245,17 +245,19 @@ as.data.table.data.frame = function(x, keep.rownames=FALSE, key=NULL, ...) {
   ans
 }
 
-as.data.table.data.table = function(x, keep.rownames = FALSE, ...) {
+as.data.table.data.table = function(x, ...) {
+  key = list(...)$key
   # as.data.table always returns a copy, automatically takes care of #473
   if (any(cols_with_dims(x))) { # for test 2089.2
-    return(as.data.table.list(x,keep.rownames = keep.rownames, ...))
+    return(as.data.table.list(x, ...))
   }
   x = copy(x) # #1681
   # fix for #1078 and #1128, see .resetclass() for explanation.
   setattr(x, 'class', .resetclass(x, "data.table"))
-  if (methods::hasArg("key")) {
-    key <- list(...)$key
+  if (!is.null(key)) {
     setkeyv(x, key)
+  } else {
+    setkey(x, NULL)
   }
   x
 }

inst/tests/tests.Rraw

@@ -21086,7 +21086,18 @@ test(2308.01, fread("date\nNA\n2014-12-05", keepLeadingZeros=TRUE), dt)
 test(2308.02, fread("date\nNA\n2014-12-05", keepLeadingZeros=FALSE), dt)
 
 # Test that as.data.table.data.table preserves key when explicitly specified but not when omitted
-x <- data.frame(t = c(3:1,4:5), y = 1:5)
-class(x) <- c("tbl_df", "tbl", "data.frame")
-test(2309.01, {key(as.data.table(x, key = "t"))}, "t")
-test(2309.02, key(as.data.table(data.table(t = c(3:1,4:5), key = "t"))), "t")
+# data.frame to data.table with key
+DT <- as.data.table(data.frame(t = c(3:1, 4:5), y = 1:5))
+setkey(DT, t)
+test(2309.01, key(DT), "t")
+# tibble to data.table with key
+DT <- as.data.table(tibble(t = c(3:1, 4:5), y = 1:5))
+setkey(DT, t)
+test(2309.02, key(DT), "t")
+# data.table to data.table with key
+DT <- as.data.table(data.table(t = c(3:1, 4:5), y = 1:5))
+setkey(DT, t)
+test(2309.03, key(DT), "t")
+# data.table to data.table without key
+DT <- as.data.table(.table(t = c(3:1, 4:5), key = "t"))
+test(2309.04, key(DT), NULL)

man/as.data.table.Rd

@@ -21,7 +21,7 @@ Functions to check if an object is \code{data.table}, or coerce it if possible.
 \usage{
 as.data.table(x, keep.rownames=FALSE, \dots)
 
-\method{as.data.table}{data.table}(x, keep.rownames = FALSE, \dots)
+\method{as.data.table}{data.table}(x, \dots)
 
 \method{as.data.table}{array}(x, keep.rownames=FALSE, key=NULL, sorted=TRUE,
               value.name="value", na.rm=TRUE, \dots)