Suppress Future Device Warnings and Startup Messages

This function evaluates an expression and selectively suppresses:

Warnings related to device state changes (e.g., opening or closing graphical devices) that occur inside future parallel workers (e.g., with multisession or multicore plans).
Package startup messages emitted during package loading in parallel workers (e.g., from ggplot2 or terra in multicore plans).

Usage

quiet_device(expr)

Arguments

expr: An R expression to evaluate. This is the code block in which graphics device warnings or startup messages from futures might occur.

Value

The result of evaluating expr, with specific future device warnings and package startup messages suppressed.

Details

When using future.apply::future_lapply() or similar parallel calls, certain functions— notably ggplot2::ggplotGrob(), cowplot::as_grob(), or ggExtra::ggMarginal()—may implicitly trigger graphics device changes (e.g., opening a PDF device internally). This causes future to emit a DeviceMisuseFutureWarning, warning that devices were added, removed, or modified within a future. Additionally, in multicore plans, forked processes may emit startup messages from packages (particularly when using future.packages argument), cluttering output. This function suppresses both types of output while allowing other warnings and messages to pass through.

Author

Ahmed El-Gabbas

Examples

if (FALSE) { # \dontrun{
  library(future)
  library(future.apply)
  library(ggplot2)
  library(parallelly)

  # Use multicore if supported, otherwise fall back to multisession
  plan_type <- ifelse(
      parallelly::supportsMulticore(), "multicore", "multisession")
  future::plan(plan_type, workers = 2, gc = TRUE)

  fun1 <- function(x) {
    # Loading ecokit triggers startup messages
    library(ecokit)

    p <- data.frame(x = rnorm(100), y = rnorm(100)) %>%
      ggplot2::ggplot(ggplot2::aes(x, y)) +
      ggplot2::geom_point()

    # this triggers device warnings
    return(grob)
  }

  # This will trigger device warnings and startup messages
  plots <- future.apply::future_lapply(1:5, fun1, future.seed = TRUE)

  # Run with suppression of device warnings and startup messages
  plots <- future.apply::future_lapply(1:5, fun1, future.seed = TRUE) %>%
    quiet_device()
  plot(plots[[1]])

  future::plan("sequential")
} # }