Running R Script at command line with commandArgs value in tidy evaluation in R programming

I have a r script, named myrsciprt.R as follows:

library(ggplot2)
library(ggpubr)
library(palmerpenguins)

create_plots_pdf <- function(output_filename, group_name){
  
  # Histogram example: flipper length by species
  gg1 <- ggplot(data = penguins, aes(x = flipper_length_mm)) +
    geom_histogram(aes(fill = {{group_name}}), alpha = 0.5, position = "identity") +
    scale_fill_manual(values = c("darkorange","darkorchid","cyan4"))
  
  
  gg2 <- # Scatterplot example 1: penguin flipper length versus body mass
    ggplot(data = penguins, aes(x = flipper_length_mm, y = body_mass_g)) +
    geom_point(aes(color = {{group_name}}, 
                   shape = {{group_name}}),
               size = 2) +
    scale_color_manual(values = c("darkorange","darkorchid","cyan4")) 
  
  
  # Jitter plot example: bill length by species
  gg3 <- ggplot(data = penguins, aes(x = {{group_name}}, y = bill_length_mm)) +
    geom_jitter(aes(color = {{group_name}}),
                width = 0.1, 
                alpha = 0.7,
                show.legend = FALSE) +
    scale_color_manual(values = c("darkorange","darkorchid","cyan4"))
  
  
  
  final_plot <- ggarrange(
    gg1,                # First row with line plot
    # Second row with box and dot plots
    ggarrange(
      gg2, gg3, ncol = 2, common.legend = TRUE,
      labels = c("B", "C"),
      legend = "bottom"
    ), 
    nrow = 2, 
    labels = "A"       # Label of the line plot
  ) 
  
  ggexport(final_plot, filename = output_filename)
}

x <- commandArgs(trailingOnly = TRUE)
variable1 <- x[1]
variable2 <- x[2]

# create_plots_pdf(data_filename = "penguins.csv",group_name = species)
create_plots_pdf(output_filename=variable1,group_name=variable2)

I run it at command line as follows: Rscript myrscript.R myplot.pdf species

It run without errors but the species value passed at the command line was not used in the plots. Can you help me review my code? I am suppecting it is the tidy evaluation syntax that might be wrong. Thank you

As SamR said, that is the problem, and the proposed solution works fine. However, the recommended solution by {ggplot} developers is to use the .data pronoum. Here is how it works:

library(ggplot2)
library(ggpubr)
library(palmerpenguins)

create_plots_pdf <- function(output_filename, group_name){
  
  # Histogram example: flipper length by species
  gg1 <- ggplot(data = penguins, aes(x = flipper_length_mm)) +
    geom_histogram(aes(fill = .data[[group_name]]), alpha = 0.5, position = "identity") +
    scale_fill_manual(values = c("darkorange","darkorchid","cyan4"))
  
  
  gg2 <- # Scatterplot example 1: penguin flipper length versus body mass
    ggplot(data = penguins, aes(x = flipper_length_mm, y = body_mass_g)) +
    geom_point(aes(color = .data[[group_name]], 
                   shape = .data[[group_name]]),
               size = 2) +
    scale_color_manual(values = c("darkorange","darkorchid","cyan4")) 
  
  
  # Jitter plot example: bill length by species
  gg3 <- ggplot(data = penguins, aes(x = .data[[group_name]], y = bill_length_mm)) +
    geom_jitter(aes(color = .data[[group_name]]),
                width = 0.1, 
                alpha = 0.7,
                show.legend = FALSE) +
    scale_color_manual(values = c("darkorange","darkorchid","cyan4"))
  
  
  
  final_plot <- ggarrange(
    gg1,                # First row with line plot
    # Second row with box and dot plots
    ggarrange(
      gg2, gg3, ncol = 2, common.legend = TRUE,
      labels = c("B", "C"),
      legend = "bottom"
    ), 
    nrow = 2, 
    labels = "A"       # Label of the line plot
  ) 
  
  ggexport(final_plot, filename = output_filename)
}

x <- commandArgs(trailingOnly = TRUE)
variable1 <- x[1]
variable2 <- x[2]

# create_plots_pdf(data_filename = "penguins.csv",group_name = species)
create_plots_pdf(output_filename=variable1,group_name=variable2)