feat: fix missing data decorators

Author: averissimo

R/tm_missing_data.R

@@ -23,7 +23,7 @@
 #' - `summary_plot` (`grob` created with [ggplot2::ggplotGrob()])
 #' - `combination_plot` (`grob` created with [ggplot2::ggplotGrob()])
 #' - `by_subject_plot` (`ggplot2`)
-#' - `table` ([DT::datatable()])
+#' - `table` (`listing_df` created with [rlistings::as_listing()])
 #'
 #' Decorators can be applied to all outputs or only to specific objects using a
 #' named list of `teal_transform_module` objects.
@@ -1392,7 +1392,12 @@ srv_missing_data <- function(id,
           card$append_plot(combination_plot_r(), dim = pws2$dim())
         } else if (sum_type == "By Variable Levels") {
           card$append_text("Table", "header3")
-          card$append_table(decorated_summary_table_q()[["table"]])
+          table <- decorated_summary_table_q()[["table"]]
+          if (nrow(table) == 0L) {
+            card$append_text("No data available for table.")
+          } else {
+            card$append_table(table)
+          }
         } else if (sum_type == "Grouped by Subject") {
           card$append_text("Plot", "header3")
           card$append_plot(by_subject_plot_r(), dim = pws3$dim())