add tests

Author: Mukulyadav2004

R/as.data.table.R

@@ -134,24 +134,30 @@ as.data.table.list = function(x,
   origListNames = if (missing(.named)) names(x) else NULL  # as.data.table called directly, not from inside data.table() which provides .named, #3854
   empty_atomic = FALSE
 
-  #Handle keep.rownames for vectors (mimicking data.frame behavior)
+  # Handle keep.rownames for vectors (mimicking data.frame behavior)
   vector_rownames = NULL
-  if(!identical(keep.rownames, FALSE)) {
-    for(i in seq_len(n)){
-      xi = x[[i]]
-      if (!is.null(xi) && is.atomic(xi) && !is.null(names(xi)) && is.null(dim(xi)) && length(names(xi)) > 0) {
-        valid_names = names(xi)
-        if(any(nzchar(valid_names))) {
+  check_rownames = !isFALSE(keep.rownames)
+  
+  for (i in seq_len(n)) {
+    xi = x[[i]]
+    if (is.null(xi)) next    # eachncol already initialized to 0 by integer() above
+    if (check_rownames && is.null(vector_rownames)) {
+      # Check for named vectors
+      if (is.atomic(xi) && !is.null(names(xi)) && is.null(dim(xi))) {
+        valid_names = names(xi) 
+        if (any(nzchar(valid_names))) {
           vector_rownames = valid_names
           x[[i]] = unname(xi)
-          break
         }
       }
-    }
-  }
-  for (i in seq_len(n)) {
-    xi = x[[i]]
-    if (is.null(xi)) next    # eachncol already initialized to 0 by integer() above
+      # Check for data.frames or matrices with explicit rownames
+      else if (!is.null(dim(xi)) && !is.null(rownames(xi))) {
+        valid_names = rownames(xi)
+        if (any(nzchar(valid_names))) {
+          vector_rownames = valid_names
+        }
+      }
+    }  
     if (!is.null(dim(xi)) && missing.check.names) check.names=TRUE
     if ("POSIXlt" %chin% class(xi)) {
       warningf("POSIXlt column type detected and converted to POSIXct. We do not recommend use of POSIXlt at all because it uses 40 bytes to store one date.")
@@ -161,7 +167,7 @@ as.data.table.list = function(x,
         if (is.matrix(xi) && NCOL(xi)<=1L && is.null(colnames(xi))) { # 1 column matrix naming #4124
           xi = x[[i]] = c(xi)
         } else {
-          xi = x[[i]] = as.data.table(xi, keep.rownames=keep.rownames)  # we will never allow a matrix to be a column; always unpack the columns
+          xi = x[[i]] = as.data.table(xi, keep.rownames=FALSE)  # we will never allow a matrix to be a column; always unpack the columns
         }
       }
       # else avoid dispatching to as.data.table.data.table (which exists and copies)

inst/tests/tests.Rraw

@@ -21371,3 +21371,16 @@ x <- c(1, 2, 3)
 y <- setNames(c(4, 5, 6), c("A", "B", "C"))  
 test(2329.1, as.data.table.list(list(x, y), keep.rownames=TRUE), data.table(rn=c("A", "B", "C"), V1=c(1, 2, 3), V2=c(4, 5, 6)))
 test(2329.2, as.data.table.list(list(x, y), keep.rownames="custom"), data.table(custom=c("A", "B", "C"), V1=c(1, 2, 3), V2=c(4, 5, 6)))
+test(2329.3, as.data.table.list(list(y, x), keep.rownames=TRUE), data.table(rn=c("A", "B", "C"), V1=c(4, 5, 6), V2=c(1, 2, 3))) 
+
+# Behavior under data.frame()
+test(2329.4, as.data.table(data.frame(x, y), keep.rownames=TRUE), data.table(rn=c("A", "B", "C"), V1=c(1, 2, 3), V2=c(4, 5, 6)))
+test(2329.5, as.data.table(data.frame(y, x), keep.rownames=TRUE), data.table(rn=c("A", "B", "C"), V1=c(4, 5, 6), V2=c(1, 2, 3)))
+
+a <- setNames(c(7, 8, 9), c("", "", ""))    # test condition about any(nzchar(valid_names))
+test(2329.6, as.data.table.list(list(a), keep.rownames=TRUE), data.table(V1=c(7, 8, 9)))
+b <- setNames(c(10, 11, 12), c("", "B", ""))
+test(2329.7, as.data.table.list(list(b), keep.rownames=TRUE), data.table(rn=c("", "B", ""), V1=c(10, 11, 12)))
+
+DF <- data.frame(row.names = letters[1:6], V = 1:6)     # Test data.frame with explicit rownames
+test(2329.8, as.data.table(list(a = 6:1, DF), keep.rownames=TRUE), data.table(rn=c("a", "b", "c", "d", "e", "f"), a=c(6, 5, 4, 3, 2, 1), V=c(1, 2, 3, 4, 5, 6)))