Ensure that text_font reaches theme_xaringan_set_defaults() when set_ggplot_defaults == TRUE

R/ggplot2.R

@@ -308,15 +308,21 @@ theme_xaringan_base <- function(
     get_theme_font("header")
   }
 
-  text_font %||% "sans"
-  title_font %||% "sans"
+  text_font  <- text_font %||% "sans"
+  title_font <- title_font %||% "sans"
 
   if (set_ggplot_defaults) {
     accent_color <- accent_color %||% xaringanthemer_env$header_color %||% text_color
     accent_secondary_color <- accent_secondary_color %||% xaringanthemer_env$text_bold_color %||% accent_color
     accent_color <- full_length_hex(accent_color)
     accent_secondary_color <- full_length_hex(accent_secondary_color)
-    theme_xaringan_set_defaults(text_color, background_color, accent_color, accent_secondary_color)
+    theme_xaringan_set_defaults(
+      text_color = text_color,
+      background_color = background_color,
+      accent_color = accent_color,
+      accent_secondary_color = accent_secondary_color,
+      text_font = text_font
+    )
   }
 
   theme <- ggplot2::theme(
@@ -459,7 +465,6 @@ theme_xaringan_restore_defaults <- function() {
     return(invisible())
   }
 
-
   old_default <- xaringanthemer_env$old_ggplot_defaults
   old_default_not_std <- vapply(old_default, function(x) length(x) > 0, logical(1))
   old_default <- old_default[old_default_not_std]
@@ -476,12 +481,16 @@ theme_xaringan_restore_defaults <- function() {
 }
 
 safely_set_geom <- function(geom, new) {
+  warn <- function(x) {
+    rlang::warn(x$message)
+    invisible()
+  }
   tryCatch(
     {
       ggplot2::update_geom_defaults(geom, new)
     },
-    error = function(e) invisible(),
-    warning = function(w) invisible()
+    error = warn,
+    warning = warn
   )
 }
 

tests/testthat/test-ggplot2.R

@@ -102,6 +102,23 @@ describe("theme_xaringan()", {
       })
     )
   })
+
+  it("correctly overwrites geom default values", {
+    fonts <- with_clean_session(function() {
+      style <- xaringanthemer::style_xaringan(outfile = NULL)
+
+      g <- ggplot2::ggplot(mtcars, ggplot2::aes(x = cyl, y = disp, label = carb))
+      fonts <- list()
+      plot1 <- g + ggplot2::geom_text() + xaringanthemer::theme_xaringan()
+      fonts[[1]] <- plot1$layers[[1]]$geom$default_aes$family
+      plot2 <- g + ggplot2::geom_text() + xaringanthemer::theme_xaringan(text_font = "Ranga", text_font_use_google = TRUE)
+      fonts[[2]] <- plot2$layers[[1]]$geom$default_aes$family
+      fonts
+    })
+
+    expect_equal(fonts[[1]], "Noto Sans")
+    expect_equal(fonts[[2]], "Ranga")
+  })
 })
 
 describe("theme_xaringan_inverse()", {