Fix #89

NEWS.md

@@ -1,5 +1,8 @@
 # ggh4x (development version)
 
+* Swapped inheritance of `facet_nested(nest_line)`: it is now a line element
+  that inherits from blank elements, and the theme default is a blank element.
+  This makes it more responsive to the theme setting (#89).
 * Anticipated compatability with future ggplot2 > 3.4.2.
 * `force_panelsizes()` gains a `total_width` and `total_height` argument to
   set the size of the total panel area.

R/facet_nested.R

@@ -66,7 +66,7 @@ facet_nested <- function(
   switch = NULL,
   drop = TRUE,
   margins = FALSE,
-  nest_line = element_blank(),
+  nest_line = element_line(inherit.blank = TRUE),
   resect = unit(0, "mm"),
   strip = strip_nested(),
   bleed = NULL
@@ -234,13 +234,15 @@ FacetNested <- ggproto(
 add_nest_indicator <- function(panels, params, theme) {
   # Convert nest line to proper element
   nest_line <- params$nest_line
-  if (is.null(nest_line) || isFALSE(nest_line) ||
-      inherits(nest_line, "element_blank")) {
+  if (is.null(nest_line) || isFALSE(nest_line)) {
     return(panels)
   }
   nest_line <- inherit_element(
     nest_line, calc_element("ggh4x.facet.nestline", theme)
   )
+  if (inherits(nest_line, "element_blank")) {
+    return(panels)
+  }
 
   # Find strips
   layout <- panels$layout

R/themes.R

@@ -26,7 +26,7 @@
 #'   used in the [`guide_axis_logticks()`] function. Defaults to `rel(1/3)`.
 ggh4x_theme_elements <- function() {
   register_theme_elements(
-    ggh4x.facet.nestline  = element_line(),
+    ggh4x.facet.nestline  = element_blank(),
     ggh4x.axis.nestline   = element_line(),
     ggh4x.axis.nestline.x = element_line(),
     ggh4x.axis.nestline.y = element_line(),