For backward compatibility, zeroGrob() returns a nullGrob() subclass

Author: teunbrand

NAMESPACE

@@ -19,7 +19,6 @@ S3method(as.list,ggproto)
 S3method(autolayer,default)
 S3method(autoplot,default)
 S3method(c,mapped_discrete)
-S3method(drawDetails,zeroGrob)
 S3method(element_grob,element_blank)
 S3method(element_grob,element_line)
 S3method(element_grob,element_point)
@@ -76,9 +75,7 @@ S3method(ggplot_gtable,ggplot_built)
 S3method(grid.draw,absoluteGrob)
 S3method(grid.draw,ggplot)
 S3method(grobHeight,absoluteGrob)
-S3method(grobHeight,zeroGrob)
 S3method(grobWidth,absoluteGrob)
-S3method(grobWidth,zeroGrob)
 S3method(grobX,absoluteGrob)
 S3method(grobY,absoluteGrob)
 S3method(guide_gengrob,default)
@@ -87,7 +84,6 @@ S3method(guide_merge,default)
 S3method(guide_train,default)
 S3method(guide_transform,default)
 S3method(heightDetails,titleGrob)
-S3method(heightDetails,zeroGrob)
 S3method(limits,Date)
 S3method(limits,POSIXct)
 S3method(limits,POSIXlt)
@@ -149,7 +145,6 @@ S3method(vec_ptype2,mapped_discrete.factor)
 S3method(vec_ptype2,mapped_discrete.integer)
 S3method(vec_ptype2,mapped_discrete.mapped_discrete)
 S3method(widthDetails,titleGrob)
-S3method(widthDetails,zeroGrob)
 export("%+%")
 export("%+replace%")
 export(.data)

R/grob-null.R

@@ -5,22 +5,6 @@
 zeroGrob <- function() .zeroGrob
 
 .zeroGrob <- NULL
-on_load(.zeroGrob <- grob(cl = "zeroGrob", name = "NULL"))
+on_load(.zeroGrob <- add_class(nullGrob(), "zeroGrob"))
 
-#' @export
-#' @method widthDetails zeroGrob
-widthDetails.zeroGrob <- function(x) unit(0, "cm")
-#' @export
-#' @method heightDetails zeroGrob
-heightDetails.zeroGrob <- function(x) unit(0, "cm")
-#' @export
-#' @method grobWidth zeroGrob
-grobWidth.zeroGrob <- function(x) unit(0, "cm")
-#' @export
-#' @method grobHeight zeroGrob
-grobHeight.zeroGrob <- function(x) unit(0, "cm")
-#' @export
-#' @method drawDetails zeroGrob
-drawDetails.zeroGrob <- function(x, recording) {}
-
-is.zero <- function(x) is.null(x) || inherits(x, "zeroGrob")
+is.zero <- function(x) is.null(x) || inherits(x, "null")

R/utilities.R

@@ -959,3 +959,12 @@ compute_data_size <- function(data, size, default = 0.9,
   data[[target]] <- res * (default %||% 0.9)
   data
 }
+
+add_class <- function(x, new_class) {
+  new_class <- setdiff(new_class, class(x))
+  if (length(new_class) < 1) {
+    return(x)
+  }
+  class(x) <- union(new_class, class(x))
+  x
+}