Add flextable connector for export_tfl()

CLAUDE.md

@@ -50,7 +50,7 @@ annotation zones, and content areas must be independently sized and never overla
 | Type        | R package (roxygen2, testthat) |
 | License     | AGPL-3 |
 | R deps      | `dplyr`, `ggplot2`, `grid`, `glue`, `rlang` |
-| Suggests    | `formatters`, `gt`, `rtables`, `testthat (>= 3.0.0)`, `withr`, `knitr`, `rmarkdown`, `tibble` |
+| Suggests    | `flextable`, `formatters`, `gt`, `rtables`, `testthat (>= 3.0.0)`, `withr`, `knitr`, `rmarkdown`, `tibble` |
 | Namespace   | All helpers unexported except `export_tfl`, `export_tfl_page`, `tfl_table`, `tfl_colspec` |
 
 ---
@@ -308,6 +308,12 @@ writetfl/
 │   │                                    rtables_to_pagelist(),
 │   │                                    .extract_rtables_annotations(),
 │   │                                    .clean_rtables(), .rtables_to_grob()
+│   ├── flextable.R                   ← export_tfl.flextable(),
+│   │                                    flextable_to_pagelist(),
+│   │                                    .extract_flextable_annotations(),
+│   │                                    .clean_flextable(),
+│   │                                    .flextable_to_grob(),
+│   │                                    .paginate_flextable()
 │   ├── reexports.R                   ← re-exports unit, gpar from grid
 │   ├── table_columns.R               ← resolve_col_specs(), compute_col_widths(),
 │   │                                    paginate_cols()
@@ -333,6 +339,7 @@ writetfl/
 │       ├── test-ggtibble.R
 │       ├── test-gt.R
 │       ├── test-rtables.R
+│       ├── test-flextable.R
 │       └── test-integration.R
 ├── vignettes/
 │   ├── writetfl.Rmd
@@ -341,7 +348,8 @@ writetfl/
 │   ├── v03-tfl_table_styling.Rmd
 │   ├── v04-troubleshooting.Rmd
 │   ├── v05-gt_tables.Rmd
-│   └── v06-rtables.Rmd
+│   ├── v06-rtables.Rmd
+│   └── v07-flextable.Rmd
 └── design/
     ├── DESIGN.md
     ├── ARCHITECTURE.md

DESCRIPTION

@@ -26,6 +26,7 @@ Imports:
     glue,
     rlang
 Suggests:
+    flextable,
     formatters,
     ggtibble,
     gt,

NAMESPACE

@@ -3,6 +3,7 @@
 S3method(drawDetails,tfl_table_grob)
 S3method(export_tfl,VTableTree)
 S3method(export_tfl,default)
+S3method(export_tfl,flextable)
 S3method(export_tfl,ggtibble)
 S3method(export_tfl,gt_tbl)
 S3method(export_tfl,list)

R/export_tfl.R

@@ -46,6 +46,13 @@
 #'   `textGrob`. Pagination uses rtables' built-in `paginate_table()`.
 #'   A list of `VTableTree` objects produces one page (or more, with
 #'   pagination) per table.
+#'
+#'   When `x` is a `flextable` object (from the \pkg{flextable} package),
+#'   the caption (from [flextable::set_caption()]) is extracted as the
+#'   caption, and footer rows (from [flextable::footnote()] or
+#'   [flextable::add_footer_lines()]) are extracted as the footnote. The
+#'   table is rendered via [flextable::gen_grob()]. A list of `flextable`
+#'   objects produces one page (or more, with pagination) per table.
 #' @param file Path to the output PDF file. Must be a single character string
 #'   ending in `".pdf"`. Not required when `preview` is not `FALSE`.
 #' @param pg_width Page width in inches.
@@ -173,7 +180,17 @@ export_tfl.list <- function(
       pages <- unlist(lapply(x, rtables_to_pagelist, pg_width, pg_height,
                             dots, page_num), recursive = FALSE)
     } else {
-      pages <- coerce_x_to_pagelist(x)
+      # Check if this is a list of flextable objects
+      all_flextable <- length(x) > 0L &&
+        all(vapply(x, inherits, logical(1L), "flextable"))
+      if (all_flextable) {
+        rlang::check_installed("flextable",
+                               reason = "to export flextable tables")
+        pages <- unlist(lapply(x, flextable_to_pagelist, pg_width, pg_height,
+                              dots, page_num), recursive = FALSE)
+      } else {
+        pages <- coerce_x_to_pagelist(x)
+      }
     }
   }
   .export_tfl_pages(pages, file, pg_width, pg_height, page_num, preview, dots)