Merge pull request 'feat(flextable): reusable Civilytics flextable branding helpers' (#10) from feat/flextable-branding into feat/stamp-logo-png

Reviewed-on: #10

DESCRIPTION

@@ -31,7 +31,10 @@ Encoding: UTF-8
 Suggests:
     testthat (>= 3.0.0),
     tidycensus,
-    quarto
+    quarto,
+    flextable,
+    officer,
+    ragg
 Config/testthat/edition: 3
 Config/roxygen2/version: 8.0.0
 RoxygenNote: 7.3.3

NAMESPACE

@@ -39,10 +39,13 @@ export(rnh)
 export(round_to_nearest_half)
 export(safe_max)
 export(safe_ratio)
+export(save_branded_flextable_png)
 export(scale_color_civilytics)
 export(scale_fill_civilytics)
 export(simpleCap)
+export(stamp_logo_png)
 export(star_subs)
+export(style_flextable_civilytics)
 export(theme_civilytics)
 export(theme_civilytics_dark)
 export(theme_civilytics_dark_map)
@@ -61,8 +64,12 @@ importFrom(ggplot2,annotation_custom)
 importFrom(ggplot2,ggplot)
 importFrom(ggplot2,theme)
 importFrom(ggplot2,theme_void)
+importFrom(grDevices,dev.off)
+importFrom(grDevices,png)
 importFrom(graphics,rasterImage)
 importFrom(grid,grid.draw)
+importFrom(grid,grid.newpage)
+importFrom(grid,grid.raster)
 importFrom(grid,rasterGrob)
 importFrom(gridExtra,arrangeGrob)
 importFrom(jpeg,readJPEG)

R/flextable.R

@@ -0,0 +1,175 @@
+#' Apply the Civilytics brand styling to a flextable
+#'
+#' Applies *only* the visual Civilytics brand to an already-structured
+#' [flextable::flextable()] — header fill and color, body font and size,
+#' zebra striping, borders, footer styling, and a fixed table layout. The
+#' caller remains responsible for table *structure*: labels
+#' ([flextable::set_header_labels()]), header/title lines
+#' ([flextable::add_header_lines()]), column widths ([flextable::width()]),
+#' alignment ([flextable::align()]), and footer text
+#' ([flextable::add_footer_lines()]). This separation keeps styling reusable
+#' across projects while leaving content decisions where they belong.
+#'
+#' `flextable`, `officer`, and `ragg` are Suggested (not Imported) to keep the
+#' base install light, so this function errors with an install hint if
+#' `flextable` is unavailable.
+#'
+#' @param ft A [flextable::flextable()] object.
+#' @param header_bg Character. Header background fill. Default `"#2c3e50"`.
+#' @param header_color Character. Header text color. Default `"white"`.
+#' @param title_fontsize Numeric. Font size for the first header line (the
+#'   title row, `i = 1`). Default `14`.
+#' @param body_fontsize Numeric. Body font size. Default `11`.
+#' @param font_name Character. Font family applied to all parts. Default
+#'   `"Arial"`.
+#' @param zebra Logical. Apply alternating-row striping to even body rows.
+#'   Default `TRUE`. Safely skipped for tables with fewer than two body rows.
+#' @param zebra_bg Character. Fill color for striped (even) body rows.
+#'   Default `"#f0f0eb"`.
+#' @param outer_border_color Character. Outer border color. Default
+#'   `"#888888"`.
+#' @param outer_border_width Numeric. Outer border width. Default `1`.
+#' @param inner_border_color Character. Inner horizontal border color (body).
+#'   Default `"#cccccc"`.
+#' @param inner_border_width Numeric. Inner horizontal border width. Default
+#'   `0.5`.
+#' @param footer_fontsize Numeric. Footer font size (applied only if a footer
+#'   part exists). Default `9`.
+#' @param footer_color Character. Footer text color. Default `"#555555"`.
+#'
+#' @return The styled [flextable::flextable()] object.
+#' @export
+#' @seealso [save_branded_flextable_png()] to export the styled table to a
+#'   logo-stamped PNG.
+#' @examples
+#' \dontrun{
+#' library(flextable)
+#' ft <- flextable(head(mtcars)) |>
+#'   add_header_lines("Motor Trend Cars") |>
+#'   add_footer_lines("Source: mtcars") |>
+#'   style_flextable_civilytics()
+#' }
+style_flextable_civilytics <- function(ft,
+                                       header_bg = "#2c3e50",
+                                       header_color = "white",
+                                       title_fontsize = 14,
+                                       body_fontsize = 11,
+                                       font_name = "Arial",
+                                       zebra = TRUE,
+                                       zebra_bg = "#f0f0eb",
+                                       outer_border_color = "#888888",
+                                       outer_border_width = 1,
+                                       inner_border_color = "#cccccc",
+                                       inner_border_width = 0.5,
+                                       footer_fontsize = 9,
+                                       footer_color = "#555555") {
+  if (!requireNamespace("flextable", quietly = TRUE)) {
+    stop("Install 'flextable' to use this function.", call. = FALSE)
+  }
+  if (!requireNamespace("officer", quietly = TRUE)) {
+    stop("Install 'officer' to use this function.", call. = FALSE)
+  }
+
+  # Header: navy fill, white bold text, larger title line.
+  ft <- flextable::bg(ft, bg = header_bg, part = "header")
+  ft <- flextable::color(ft, color = header_color, part = "header")
+  ft <- flextable::bold(ft, part = "header")
+  ft <- flextable::fontsize(ft, i = 1, size = title_fontsize, part = "header")
+
+  # Body: readable size, brand font across all parts.
+  ft <- flextable::fontsize(ft, size = body_fontsize, part = "body")
+  ft <- flextable::font(ft, fontname = font_name, part = "all")
+
+  # Zebra striping on even body rows, guarded for tables with < 2 rows.
+  nrow_body <- flextable::nrow_part(ft, part = "body")
+  if (zebra && nrow_body >= 2) {
+    ft <- flextable::bg(ft, i = seq(2, nrow_body, 2), bg = zebra_bg,
+                        part = "body")
+  }
+
+  # Borders: outer frame on all parts, light horizontal rules in the body.
+  ft <- flextable::border_outer(
+    ft,
+    border = officer::fp_border(color = outer_border_color,
+                                width = outer_border_width),
+    part = "all"
+  )
+  ft <- flextable::border_inner_h(
+    ft,
+    border = officer::fp_border(color = inner_border_color,
+                                width = inner_border_width),
+    part = "body"
+  )
+
+  # Footer styling — only if the table actually has a footer part.
+  if (flextable::nrow_part(ft, part = "footer") > 0) {
+    ft <- flextable::fontsize(ft, size = footer_fontsize, part = "footer")
+    ft <- flextable::color(ft, color = footer_color, part = "footer")
+  }
+
+  flextable::set_table_properties(ft, layout = "fixed")
+}
+
+
+#' Save a branded flextable to a logo-stamped PNG
+#'
+#' Exports a styled [flextable::flextable()] to a PNG via
+#' [ragg::agg_png()] (sized to the table's own dimensions plus a little
+#' headroom for the logo), then optionally stamps the Civilytics logo onto the
+#' file with [stamp_logo_png()] so file-based tables stay visually consistent
+#' with [civilytics_logo()]-branded plots.
+#'
+#' `ragg` and `flextable` are Suggested (not Imported); this function errors
+#' with an install hint if either is unavailable.
+#'
+#' @param ft A [flextable::flextable()] object, typically already styled with
+#'   [style_flextable_civilytics()].
+#' @param path Character. Output PNG path. Returned invisibly.
+#' @param logo Logical. Stamp the Civilytics logo onto the saved PNG via
+#'   [stamp_logo_png()]. Default `TRUE`.
+#' @param res Numeric. Output resolution in PPI passed to [ragg::agg_png()].
+#'   Default `300`.
+#' @param extra_height Numeric. Additional height in inches added to the
+#'   table's natural height to leave room for the stamped logo. Default `0.4`.
+#' @param ... Additional arguments forwarded to [stamp_logo_png()] (e.g.
+#'   `type`, `variant`, `position`, `width_frac`, `margin_frac`).
+#'
+#' @return `path`, invisibly.
+#' @export
+#' @seealso [style_flextable_civilytics()] to apply the brand styling, and
+#'   [stamp_logo_png()] for the underlying logo compositing.
+#' @examples
+#' \dontrun{
+#' library(flextable)
+#' ft <- flextable(head(mtcars)) |>
+#'   add_footer_lines("Source: mtcars") |>
+#'   style_flextable_civilytics()
+#' save_branded_flextable_png(ft, "table.png")
+#' save_branded_flextable_png(ft, "table.png", position = "bottom-left")
+#' knitr::include_graphics("table.png")
+#' }
+save_branded_flextable_png <- function(ft, path, logo = TRUE, res = 300,
+                                       extra_height = 0.4, ...) {
+  if (!requireNamespace("flextable", quietly = TRUE)) {
+    stop("Install 'flextable' to use this function.", call. = FALSE)
+  }
+  if (!requireNamespace("ragg", quietly = TRUE)) {
+    stop("Install 'ragg' to use this function.", call. = FALSE)
+  }
+
+  d <- flextable::flextable_dim(ft)
+  ragg::agg_png(path, width = d$width, height = d$height + extra_height,
+                units = "in", res = res)
+  on.exit(grDevices::dev.off(), add = TRUE)
+  plot(ft)
+
+  if (logo) {
+    # dev.off() must run before stamp_logo_png() re-reads the file. Flush the
+    # device now and clear the on.exit handler so it does not fire twice.
+    grDevices::dev.off()
+    on.exit()
+    stamp_logo_png(path, ...)
+  }
+
+  invisible(path)
+}

R/logo.R

@@ -361,3 +361,92 @@ civilytics_logo <- function(plot,
            position = position)
 }
 
+
+#' Stamp the Civilytics logo onto a saved raster (PNG) image
+#'
+#' The raster analogue of [civilytics_logo()] for outputs that are already
+#' rendered to a file rather than held as a ggplot/grob — e.g. a `flextable`
+#' exported to PNG, or any `grDevices::png()` / `ragg::agg_png()` output.
+#' Resolves the *same* brand asset that [make_logo_grob()] uses, so file-based
+#' tables stay visually consistent with logo-branded plots, and composites it
+#' into a corner of the image. Pure base-graphics + grid + png — no new
+#' package dependencies.
+#'
+#' @param path Character. Path to the PNG to stamp. The file is overwritten
+#'   in place at its original pixel dimensions.
+#' @param type Character. `"wordmark"` (default) or `"mark"`. As in
+#'   [make_logo_grob()].
+#' @param variant Character. `"light"` (default, dark logo for light
+#'   backgrounds) or `"dark"` (reverse logo for dark backgrounds).
+#' @param position Character. Corner placement: `"bottom-right"` (default),
+#'   `"bottom-left"`, `"top-right"`, or `"top-left"`.
+#' @param width_frac Numeric. Logo width as a fraction of the image width
+#'   (default `0.15`). Height follows from the logo's aspect ratio.
+#' @param margin_frac Numeric. Padding from the edges as a fraction of the
+#'   image width (default `0.02`).
+#'
+#' @return `path`, invisibly.
+#' @export
+#' @importFrom png readPNG
+#' @importFrom grid grid.newpage grid.raster
+#' @importFrom grDevices png dev.off
+#' @examples
+#' \dontrun{
+#' # Brand a table exported to PNG so it matches civilytics_logo()-branded plots
+#' ragg::agg_png("table.png", width = 8, height = 4, units = "in", res = 200)
+#' plot(flextable::flextable(head(mtcars)))
+#' dev.off()
+#' stamp_logo_png("table.png")                         # wordmark, bottom-right
+#' stamp_logo_png("table.png", type = "mark", position = "bottom-left")
+#' }
+stamp_logo_png <- function(path,
+                           type = c("wordmark", "mark"),
+                           variant = c("light", "dark"),
+                           position = c("bottom-right", "bottom-left",
+                                        "top-right", "top-left"),
+                           width_frac = 0.15,
+                           margin_frac = 0.02) {
+  type     <- match.arg(type)
+  variant  <- match.arg(variant)
+  position <- match.arg(position)
+  stopifnot(file.exists(path))
+
+  # Same asset selection as make_logo_grob() so files match branded plots.
+  img_file <- switch(
+    paste(type, variant, sep = "_"),
+    wordmark_light = "civilytics-wordmark.png",
+    wordmark_dark  = "civilytics-wordmark-reverse.png",
+    mark_light     = "civilytics-mark.png",
+    mark_dark      = "civilytics-mark-reverse.png"
+  )
+  logo_path <- system.file("img", img_file, package = "civilytics")
+  if (!nzchar(logo_path)) {
+    stop("Civilytics logo asset not found in the 'civilytics' package: ", img_file)
+  }
+
+  base_img <- png::readPNG(path)        # height x width x channels, values in [0, 1]
+  logo_img <- png::readPNG(logo_path)
+  h <- dim(base_img)[1]
+  w <- dim(base_img)[2]
+  aspect <- dim(logo_img)[1] / dim(logo_img)[2]   # logo height / width
+
+  # Sizes/margins are expressed relative to image WIDTH, then converted to the
+  # device's npc units (which scale with the viewport's own width and height).
+  lw <- width_frac
+  lh <- width_frac * aspect * (w / h)
+  mx <- margin_frac
+  my <- margin_frac * (w / h)
+
+  x <- if (grepl("right", position)) 1 - mx else mx
+  y <- if (grepl("top",   position)) 1 - my else my
+  just <- c(if (grepl("right", position)) "right" else "left",
+            if (grepl("top",   position)) "top"   else "bottom")
+
+  grDevices::png(path, width = w, height = h, units = "px")
+  on.exit(grDevices::dev.off(), add = TRUE)
+  grid::grid.newpage()
+  grid::grid.raster(base_img, width = 1, height = 1, interpolate = FALSE)
+  grid::grid.raster(logo_img, x = x, y = y, width = lw, height = lh,
+                    just = just, interpolate = TRUE)
+  invisible(path)
+}

man/save_branded_flextable_png.Rd

@@ -0,0 +1,62 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/flextable.R
+\name{save_branded_flextable_png}
+\alias{save_branded_flextable_png}
+\title{Save a branded flextable to a logo-stamped PNG}
+\usage{
+save_branded_flextable_png(
+  ft,
+  path,
+  logo = TRUE,
+  res = 300,
+  extra_height = 0.4,
+  ...
+)
+}
+\arguments{
+\item{ft}{A [flextable::flextable()] object, typically already styled with
+[style_flextable_civilytics()].}
+
+\item{path}{Character. Output PNG path. Returned invisibly.}
+
+\item{logo}{Logical. Stamp the Civilytics logo onto the saved PNG via
+[stamp_logo_png()]. Default `TRUE`.}
+
+\item{res}{Numeric. Output resolution in PPI passed to [ragg::agg_png()].
+Default `300`.}
+
+\item{extra_height}{Numeric. Additional height in inches added to the
+table's natural height to leave room for the stamped logo. Default `0.4`.}
+
+\item{...}{Additional arguments forwarded to [stamp_logo_png()] (e.g.
+`type`, `variant`, `position`, `width_frac`, `margin_frac`).}
+}
+\value{
+`path`, invisibly.
+}
+\description{
+Exports a styled [flextable::flextable()] to a PNG via
+[ragg::agg_png()] (sized to the table's own dimensions plus a little
+headroom for the logo), then optionally stamps the Civilytics logo onto the
+file with [stamp_logo_png()] so file-based tables stay visually consistent
+with [civilytics_logo()]-branded plots.
+}
+\details{
+`ragg` and `flextable` are Suggested (not Imported); this function errors
+with an install hint if either is unavailable.
+}
+\examples{
+\dontrun{
+library(flextable)
+ft <- flextable(head(mtcars)) |>
+  add_footer_lines("Source: mtcars") |>
+  style_flextable_civilytics()
+save_branded_flextable_png(ft, "table.png")
+save_branded_flextable_png(ft, "table.png", position = "bottom-left")
+knitr::include_graphics("table.png")
+}
+}
+\seealso{
+[style_flextable_civilytics()] to apply the brand styling, and
+  [stamp_logo_png()] for the underlying logo compositing.
+}

man/stamp_logo_png.Rd

@@ -0,0 +1,56 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/logo.R
+\name{stamp_logo_png}
+\alias{stamp_logo_png}
+\title{Stamp the Civilytics logo onto a saved raster (PNG) image}
+\usage{
+stamp_logo_png(
+  path,
+  type = c("wordmark", "mark"),
+  variant = c("light", "dark"),
+  position = c("bottom-right", "bottom-left", "top-right", "top-left"),
+  width_frac = 0.15,
+  margin_frac = 0.02
+)
+}
+\arguments{
+\item{path}{Character. Path to the PNG to stamp. The file is overwritten
+in place at its original pixel dimensions.}
+
+\item{type}{Character. `"wordmark"` (default) or `"mark"`. As in
+[make_logo_grob()].}
+
+\item{variant}{Character. `"light"` (default, dark logo for light
+backgrounds) or `"dark"` (reverse logo for dark backgrounds).}
+
+\item{position}{Character. Corner placement: `"bottom-right"` (default),
+`"bottom-left"`, `"top-right"`, or `"top-left"`.}
+
+\item{width_frac}{Numeric. Logo width as a fraction of the image width
+(default `0.15`). Height follows from the logo's aspect ratio.}
+
+\item{margin_frac}{Numeric. Padding from the edges as a fraction of the
+image width (default `0.02`).}
+}
+\value{
+`path`, invisibly.
+}
+\description{
+The raster analogue of [civilytics_logo()] for outputs that are already
+rendered to a file rather than held as a ggplot/grob — e.g. a `flextable`
+exported to PNG, or any `grDevices::png()` / `ragg::agg_png()` output.
+Resolves the *same* brand asset that [make_logo_grob()] uses, so file-based
+tables stay visually consistent with logo-branded plots, and composites it
+into a corner of the image. Pure base-graphics + grid + png — no new
+package dependencies.
+}
+\examples{
+\dontrun{
+# Brand a table exported to PNG so it matches civilytics_logo()-branded plots
+ragg::agg_png("table.png", width = 8, height = 4, units = "in", res = 200)
+plot(flextable::flextable(head(mtcars)))
+dev.off()
+stamp_logo_png("table.png")                         # wordmark, bottom-right
+stamp_logo_png("table.png", type = "mark", position = "bottom-left")
+}
+}

man/style_flextable_civilytics.Rd

@@ -0,0 +1,92 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/flextable.R
+\name{style_flextable_civilytics}
+\alias{style_flextable_civilytics}
+\title{Apply the Civilytics brand styling to a flextable}
+\usage{
+style_flextable_civilytics(
+  ft,
+  header_bg = "#2c3e50",
+  header_color = "white",
+  title_fontsize = 14,
+  body_fontsize = 11,
+  font_name = "Arial",
+  zebra = TRUE,
+  zebra_bg = "#f0f0eb",
+  outer_border_color = "#888888",
+  outer_border_width = 1,
+  inner_border_color = "#cccccc",
+  inner_border_width = 0.5,
+  footer_fontsize = 9,
+  footer_color = "#555555"
+)
+}
+\arguments{
+\item{ft}{A [flextable::flextable()] object.}
+
+\item{header_bg}{Character. Header background fill. Default `"#2c3e50"`.}
+
+\item{header_color}{Character. Header text color. Default `"white"`.}
+
+\item{title_fontsize}{Numeric. Font size for the first header line (the
+title row, `i = 1`). Default `14`.}
+
+\item{body_fontsize}{Numeric. Body font size. Default `11`.}
+
+\item{font_name}{Character. Font family applied to all parts. Default
+`"Arial"`.}
+
+\item{zebra}{Logical. Apply alternating-row striping to even body rows.
+Default `TRUE`. Safely skipped for tables with fewer than two body rows.}
+
+\item{zebra_bg}{Character. Fill color for striped (even) body rows.
+Default `"#f0f0eb"`.}
+
+\item{outer_border_color}{Character. Outer border color. Default
+`"#888888"`.}
+
+\item{outer_border_width}{Numeric. Outer border width. Default `1`.}
+
+\item{inner_border_color}{Character. Inner horizontal border color (body).
+Default `"#cccccc"`.}
+
+\item{inner_border_width}{Numeric. Inner horizontal border width. Default
+`0.5`.}
+
+\item{footer_fontsize}{Numeric. Footer font size (applied only if a footer
+part exists). Default `9`.}
+
+\item{footer_color}{Character. Footer text color. Default `"#555555"`.}
+}
+\value{
+The styled [flextable::flextable()] object.
+}
+\description{
+Applies *only* the visual Civilytics brand to an already-structured
+[flextable::flextable()] — header fill and color, body font and size,
+zebra striping, borders, footer styling, and a fixed table layout. The
+caller remains responsible for table *structure*: labels
+([flextable::set_header_labels()]), header/title lines
+([flextable::add_header_lines()]), column widths ([flextable::width()]),
+alignment ([flextable::align()]), and footer text
+([flextable::add_footer_lines()]). This separation keeps styling reusable
+across projects while leaving content decisions where they belong.
+}
+\details{
+`flextable`, `officer`, and `ragg` are Suggested (not Imported) to keep the
+base install light, so this function errors with an install hint if
+`flextable` is unavailable.
+}
+\examples{
+\dontrun{
+library(flextable)
+ft <- flextable(head(mtcars)) |>
+  add_header_lines("Motor Trend Cars") |>
+  add_footer_lines("Source: mtcars") |>
+  style_flextable_civilytics()
+}
+}
+\seealso{
+[save_branded_flextable_png()] to export the styled table to a
+  logo-stamped PNG.
+}

tests/testthat/test_flextable.R

@@ -0,0 +1,89 @@
+test_that("style_flextable_civilytics returns a styled flextable", {
+  skip_if_not_installed("flextable")
+  skip_if_not_installed("officer")
+
+  ft <- flextable::flextable(head(mtcars, 4))
+  ft <- flextable::add_footer_lines(ft, "Source: mtcars")
+  styled <- style_flextable_civilytics(ft)
+
+  expect_s3_class(styled, "flextable")
+  # Fixed layout is the documented end-state of the styling.
+  expect_identical(styled$properties$layout, "fixed")
+})
+
+test_that("style_flextable_civilytics is idempotent on a 1-row table (no zebra error)", {
+  skip_if_not_installed("flextable")
+  skip_if_not_installed("officer")
+
+  ft <- flextable::flextable(head(mtcars, 1))
+  expect_no_error(once <- style_flextable_civilytics(ft))
+  # Re-styling an already-styled table must not error either.
+  expect_no_error(twice <- style_flextable_civilytics(once))
+  expect_s3_class(twice, "flextable")
+})
+
+test_that("zebra = FALSE still returns a valid flextable", {
+  skip_if_not_installed("flextable")
+  skip_if_not_installed("officer")
+
+  ft <- flextable::flextable(head(mtcars, 6))
+  expect_s3_class(style_flextable_civilytics(ft, zebra = FALSE), "flextable")
+})
+
+test_that("save_branded_flextable_png writes a PNG with plausible dimensions", {
+  skip_if_not_installed("flextable")
+  skip_if_not_installed("officer")
+  skip_if_not_installed("ragg")
+  skip_if_not_installed("png")
+
+  ft <- flextable::flextable(head(mtcars, 4))
+  ft <- flextable::add_footer_lines(ft, "Source: mtcars")
+  ft <- style_flextable_civilytics(ft)
+
+  path <- tempfile(fileext = ".png")
+  on.exit(unlink(path), add = TRUE)
+
+  out <- save_branded_flextable_png(ft, path)
+
+  expect_identical(out, path)
+  expect_true(file.exists(path))
+
+  dims <- dim(png::readPNG(path))
+  # height x width x channels — a real table is at least a few hundred px each.
+  expect_gt(dims[1], 50)
+  expect_gt(dims[2], 50)
+})
+
+test_that("save_branded_flextable_png with logo = FALSE skips stamping but still writes", {
+  skip_if_not_installed("flextable")
+  skip_if_not_installed("officer")
+  skip_if_not_installed("ragg")
+  skip_if_not_installed("png")
+
+  ft <- style_flextable_civilytics(flextable::flextable(head(mtcars, 3)))
+
+  path <- tempfile(fileext = ".png")
+  on.exit(unlink(path), add = TRUE)
+
+  save_branded_flextable_png(ft, path, logo = FALSE)
+  expect_true(file.exists(path))
+  expect_gt(file.info(path)$size, 0)
+})
+
+test_that("extra_height increases the exported PNG height", {
+  skip_if_not_installed("flextable")
+  skip_if_not_installed("officer")
+  skip_if_not_installed("ragg")
+  skip_if_not_installed("png")
+
+  ft <- style_flextable_civilytics(flextable::flextable(head(mtcars, 4)))
+
+  path_small <- tempfile(fileext = ".png")
+  path_big <- tempfile(fileext = ".png")
+  on.exit(unlink(c(path_small, path_big)), add = TRUE)
+
+  save_branded_flextable_png(ft, path_small, logo = FALSE, extra_height = 0)
+  save_branded_flextable_png(ft, path_big, logo = FALSE, extra_height = 2)
+
+  expect_gt(dim(png::readPNG(path_big))[1], dim(png::readPNG(path_small))[1])
+})

tests/testthat/test_logo.R

@@ -0,0 +1,30 @@
+test_that("stamp_logo_png preserves image dimensions and returns the path invisibly", {
+  p <- tempfile(fileext = ".png")
+  on.exit(unlink(p), add = TRUE)
+  grDevices::png(p, width = 600, height = 240); plot(1:5); grDevices::dev.off()
+  in_dim <- dim(png::readPNG(p))[1:2]
+
+  expect_invisible(out <- stamp_logo_png(p))
+  expect_identical(out, p)
+  expect_identical(dim(png::readPNG(p))[1:2], in_dim)  # overwritten at same size
+})
+
+test_that("stamp_logo_png runs for every type/variant/position combination", {
+  p <- tempfile(fileext = ".png")
+  on.exit(unlink(p), add = TRUE)
+  grDevices::png(p, width = 500, height = 200); plot(1:5); grDevices::dev.off()
+
+  for (ty in c("wordmark", "mark")) {
+    for (va in c("light", "dark")) {
+      for (pos in c("bottom-right", "bottom-left", "top-right", "top-left")) {
+        expect_no_error(stamp_logo_png(p, type = ty, variant = va, position = pos))
+      }
+    }
+  }
+})
+
+test_that("stamp_logo_png validates its inputs", {
+  expect_error(stamp_logo_png(tempfile(fileext = ".png")))  # file does not exist
+  # invalid type is rejected by match.arg() before the file is touched
+  expect_error(stamp_logo_png(tempfile(fileext = ".png"), type = "banner"))
+})