Make mcmc_pairs() return a ggplot object instead of a bayesplot_group object (Fix stan-dev#268)

Author: billdenney

NEWS.md

@@ -4,6 +4,11 @@
 
 Items for next release go here
 
+### Breaking changes
+
+* `mcmc_pairs()` now returns a ggplot object rather than a `bayesplot_grid`
+  object.  Code that modified the output of `mcmc_pairs()` will need to change.
+  (#268, @billdenney)
 
 # bayesplot 1.8.0
 

R/mcmc-distributions.R

@@ -323,12 +323,8 @@ mcmc_violin <- function(x,
   n_param <- num_params(data)
 
   graph <- ggplot(data, aes(x = ~ value)) +
-    geom_histogram(
-      set_hist_aes(freq),
-      fill = get_color("mid"),
-      color = get_color("mid_highlight"),
-      size = .25,
-      na.rm = TRUE,
+    geom_mcmc_hist(
+      freq = freq, 
       binwidth = binwidth,
       breaks = breaks
     )
@@ -450,3 +446,4 @@ mcmc_violin <- function(x,
     yaxis_title(on = n_param == 1 && violin) +
     xaxis_title(on = n_param == 1)
 }
+