[write] table column names have to be characters (#1071)

src/helper_functions.cpp

@@ -477,6 +477,8 @@ void wide_to_long(
 
  auto startcol = start_col;
 
+ int32_t in_string_nums = string_nums;
+
  // pointer magic. even though these are extracted, they just point to the
  // memory in the data frame
  Rcpp::CharacterVector zz_row_r = Rcpp::as<Rcpp::CharacterVector>(zz["row_r"]);
@@ -514,7 +516,7 @@ void wide_to_long(
 
  int8_t vtyp = (int8_t)vtyps[i];
  // if colname is provided, the first row is always a character
- if (ColNames & (j == 0)) vtyp = character;
+ if (ColNames && j == 0) vtyp = character;
  std::string vals = Rcpp::as<std::string>(cvec[j]);
  std::string row = std::to_string(startrow);
 
@@ -524,8 +526,13 @@ void wide_to_long(
  if (ref_str.compare("0") == 0)
  ref_str = col + row;
 
- // factors can be numeric or string or both
- if (vtyp == factor) string_nums = true;
+ // factors can be numeric or string or both. tables require the
+ // column name to be character and once we have overwritten for
+ // a factor, we have to reset string_nums.
+ if (!(ColNames && j == 0) && vtyp == factor)
+ string_nums = 1;
+ else
+ string_nums = in_string_nums;
 
  // create struct
  celltyp cell;

tests/testthat/test-tables.R

@@ -203,3 +203,23 @@ test_that("updating table works", {
  expect_equal(got, "A1:J4")
 
 })
+
+test_that("writing table headers with factor variables works", {
+ df <- data.frame(
+ fct = structure(
+ 1:2,
+ levels = c(
+ "one",
+ "two"
+ ),
+ class = "factor"),
+ `1` = 1:2,
+ check.names = FALSE
+ )
+
+ wb <- wb_workbook()$add_worksheet()$add_data_table(x = df)
+
+ exp <- "<is><t>1</t></is>"
+ got <- wb$worksheets[[1]]$sheet_data$cc$is[[2]]
+ expect_equal(exp, got)
+})