Create icons for different flavours in a react native project. Uses bash because macOS comes with it

generate-icons.sh

#!/usr/bin/env bash

typeset -a FLAVORS

####
# This creates icons in all the necessary sizes for a react native project
# To use, simply set the variables after this block
# Note, this expects your standard icon to be named `icon.png`, and
# all flavor icons to be named `icon_<flavor>.png`. For example,
# `icon_dogfood.png` and `icon_nightly.png`
#
# You'll also need to `yarn add -D yo generator-rn-toolbox` first.
#
# Instructions:
#   - Put this script in your project somewhere
#   - Make it executable (chmod +x /path/to/generate-icons.sh
#   - Update the variables below
#   - run `/path/to/generate-icons.sh`
#   - If you get a conflict on your first run, choose 'y' to overwrite the old icons
####

PROJECT_NAME="my-cool-project" # the name of your project (take a look at app.json if you aren't sure)
ICON_LOCATION="assets/icons" # where do your raw, full-size icons live, relative to your project root (no trailing slash)
FLAVORS=("dogfood" "nightly") # enter all your flavors in between the parentheses, separated by a space.
# you'll need to have imagemagick installed so that rn-toolbox can resize
if ! which convert > /dev/null; then
  echo "You must have imagemagick installed"
  echo "Try \`brew install imagemagick\`"
  exit 1
fi

function _run_command() {
  local ICON_NAME="icon"
  local ANDROID_LOCATION=""
  local IOS_ASSET_NAME=""

  if [ "$1" != "" ]; then
    ICON_NAME="icon_$1"
    ANDROID_LOCATION="--androidSrcDirectory $1"
    local ios_sub=$( echo "${1:0:1}" | tr '[:lower:]' '[:upper:]' )
    ios_sub="$ios_sub${1:1}"
    IOS_ASSET_NAME="--iosAssetName AppIcon.$ios_sub"
  fi

  yarn yo rn-toolbox:assets \
    --projectName "$PROJECT_NAME" \
    --icon "$ICON_LOCATION/$ICON_NAME".png \
    $ANDROID_LOCATION $IOS_ASSET_NAME
}

echo "Generating icons for release"
_run_command

for flavor in "${FLAVORS[@]}"; do
  echo "Generating icons for $flavor"
  _run_command $flavor
done