Merge repeated cells

[JanMarvin]

Based on ycphs/openxlsx#341

library(openxlsx2)

df <- with(esoph, esoph[order(agegp, alcgp, tobgp), ])[1:30, ]

wb <- wb_workbook()$add_worksheet()$add_data(x = df)

wb_merge_and_border <- function(wb, x, col, has_colname = TRUE) {
  for (i in seq_along(x)) {
    if (inherits(x[[i]], "ordered")) {
      x$Subgroup <- data.table::rleid(x[[i]])
      
      for (g in unique(x$Subgroup)) {
        sel <- x$Subgroup == g
        idxs <- which(sel)
        dups <- duplicated(x$Subgroup[sel])
        dups <- idxs[dups]
        if (length(dups)) {
          dims <- wb_dims(cols = i, rows = dups, 
                          from_row = 1 + has_colname)
          wb$add_data(x = rep(NA, length(dups)), dims = dims, na.strings = NULL)
        }
        
        dims <- wb_dims(cols = i, rows = idxs,
                        from_row = 1 + has_colname)
        if (grepl(":", dims)) {
          wb$merge_cells(dims = dims)
        }
        wb$add_cell_style(dims = dims, vertical = "center", horizontal = "center")
        wb$add_border(dims = dims)
      }
    } else {
      dims <- wb_dims(cols = i, rows = seq_len(length(x[[i]])),
                      from_row = 1 + has_colname)
      wb$add_border(dims = dims, inner_hgrid = "thin", inner_vgrid = "thin",
                    inner_hcolor = wb_color(theme = 1), inner_vcolor = wb_color(theme = 1))
    }
  }
}

wb_merge_and_border(wb, df)

if (interactive()) wb$open()