Merge branch 'issue_1916' of https://github.com/Rdatatable/data.table into issue_1916

Author: Mukulyadav2004

R/as.data.table.R

@@ -146,12 +146,12 @@ as.data.table.list = function(x,
     if (is.null(xi)) next    # eachncol already initialized to 0 by integer() above
     if (check_rownames && is.null(rownames_)) {
       if (is.null(dim(xi))) {
-        if (!is.null(nm <- names(xi)) && any(nzchar(nm))) {
+        if (!is.null(nm <- names(xi))) {
           rownames_ = nm
           x[[i]] = unname(xi)
         }
       } else {
-        if (!is.null(nm <- rownames(xi)) && any(nzchar(nm))) {
+        if (!is.null(nm <- rownames(xi))) {
           rownames_ = nm
         }
       }

inst/tests/tests.Rraw

@@ -21418,10 +21418,5 @@ test(2330.3, as.data.table(list(y, x), keep.rownames=TRUE), data.table(rn=c("A",
 test(2330.4, as.data.table(data.frame(x, y), keep.rownames=TRUE), data.table(rn=c("A", "B", "C"), x=1:3, y=4:6))
 test(2330.5, as.data.table(data.frame(y, x), keep.rownames=TRUE), data.table(rn=c("A", "B", "C"), y=4:6, x=1:3))
 
-a <- setNames(7:9, c("", "", ""))    # test condition about any(nzchar(valid_names))
-test(2330.6, as.data.table(list(a), keep.rownames=TRUE), data.table(V1=7:9))
-b <- setNames(10:12, c("", "B", ""))
-test(2330.7, as.data.table(list(b), keep.rownames=TRUE), data.table(rn=c("", "B", ""), V1=10:12))
-
 DF <- data.frame(row.names = letters[1:6], V = 1:6)     # Test data.frame with explicit rownames
-test(2330.8, as.data.table(list(a = 6:1, DF), keep.rownames=TRUE), data.table(rn=letters[1:6], a=6:1, V=1:6))
+test(2330.6, as.data.table(list(a = 6:1, DF), keep.rownames=TRUE), data.table(rn=letters[1:6], a=6:1, V=1:6))