how to brew install --cask itch.app to /Applications

All of my other apps install to /Applications (which is what I want), but the itch.app installs to ~/Applications instead. I tried brew reinstall --cask --appdir /Applications itch, but that just reinstalled it to ~/Applications. Any advice? Thanks.

Solution

You can view the cask script of itch by running:

brew cask edit itch

You will see:

cask "itch" do
  version "1.18.0"
  sha256 "cfc76d52483d3e649026f29ddb6f136207964ea54eee996ee62a7a4e17326e05"

  url "https://broth.itch.ovh/itch-setup/darwin-amd64/#{version}/archive/default",
      verified: "broth.itch.ovh/"
  appcast "https://github.com/itchio/itch-setup/releases.atom"
  name "itch.io"
  homepage "https://itch.io/app"

  installer script: "itch-setup"

  uninstall delete: [
    "~/Applications/itch.app",
    "~/Library/Application Support/itch-setup/",
  ],
            quit:   "io.itch.mac"

  zap trash: [
    "~/Library/Application Support/itch/",
    "~/Library/Preferences/io.itch.mac.helper.plist",
    "~/Library/Preferences/io.itch.mac.plist",
  ]
end

The folder ~/Application is defined only in the uninstall section. It means that it's itch itself that define ~/Application as its installation directory. You can maybe hack itch to change that but you cannot change this at the Homebrew level.