envreportutils::png_retina & purrr troubles

purrr_save_plots.R

library(dplyr)
library(ggplot2)
library(purrr)

# make a small df
planets_i_know <- c("Tatooine", "Naboo", "Alderaan", "Endor")

data <- starwars %>%
  filter(!is.na(homeworld)) %>%
  group_by(homeworld, gender) %>%
  summarise(num_char = n()) %>% 
  filter(homeworld %in% planets_i_know)

# plot for one planet
plot <- data %>% 
  filter(homeworld == "Tatooine") %>% 
  ggplot() +
  geom_col(aes(gender, num_char)) +
  labs(title = "Tatooine")

# plots for all planets - saved to a list object
plots <-
  data %>%
  split(.$homeworld) %>%
  map(~ ggplot(.) +
        geom_col(aes(gender, num_char)) +
        labs(title = .$homeworld))

# look at one plot in list object
plots[["Tatooine"]]

# look at all the plots in the list object
walk(plots, ~ {
  plot(.x)
})

# save plots in list as pngs using ggsave() - THIS WORKS
iwalk(.x = plots,
      ~ ggsave(filename = paste0(.y, "_ggsave.png"),
               plot = .x))

# save plots in list as pngs using png() - THIS WORKS
iwalk(.x = plots,
      ~ {png(filename = paste0(.y, "_png.png"))
      plot(.x)
      dev.off()
      })

# save plots in list as pngs using envreportutils::png_retina() - THIS DOES NOT WORK
library(envreportutils) #installed with remotes::install_github("bcgov/envreportutils")
iwalk(.x = plots,
      ~ {png_retina(filename = paste0(.y, "_retina.png"))
        plot(.x)
        dev.off()
      })

Works:

lapply(names(plots), function(x) {
  png(filename = paste0(x, "_retina.png"))
  plot(plots[[x]])
  dev.off()
})

Doesn't work:

lapply(names(plots), function(x) {
  png_retina(filename = paste0(x, "_retina.png"))
  plot(plots[[x]])
  dev.off()
})