Add appimage support for linux

Library/Homebrew/cask/artifact.rb

@@ -2,6 +2,7 @@
 # frozen_string_literal: true
 
 require "cask/artifact/app"
+require "cask/artifact/appimage"
 require "cask/artifact/artifact" # generic 'artifact' stanza
 require "cask/artifact/audio_unit_plugin"
 require "cask/artifact/binary"
@@ -54,6 +55,8 @@ module Artifact
       ::Cask::Artifact::Vst3Plugin,
     ].freeze
 
-    LINUX_ONLY_ARTIFACTS = T.let([].freeze, T::Array[T.untyped])
+    LINUX_ONLY_ARTIFACTS = [
+      ::Cask::Artifact::AppImage,
+    ].freeze
   end
 end

Library/Homebrew/cask/artifact/appimage.rb

@@ -0,0 +1,15 @@
+# typed: strict
+# frozen_string_literal: true
+
+require "cask/artifact/symlinked"
+
+module Cask
+  module Artifact
+    class AppImage < Symlinked
+      sig { params(target: T.any(String, Pathname)).returns(Pathname) }
+      def resolve_target(target)
+        Pathname.new("#{config.appimagedir}/#{target}")
+      end
+    end
+  end
+end

Library/Homebrew/cask/cask.rb

@@ -181,11 +181,11 @@ def supports_linux?
 
       # Cache the os value before contains_os_specific_artifacts? refreshes the cask
       # (the refresh clears @dsl.os in generic/non-OS-specific contexts)
-      os_value = @dsl.os
+      on_system_blocks_exist = @dsl.on_system_blocks_exist?
 
       return false if contains_os_specific_artifacts?
 
-      os_value.present?
+      on_system_blocks_exist
     end
 
     sig { returns(T::Boolean) }

Library/Homebrew/cask/config.rb

@@ -16,6 +16,7 @@ class Config
     DEFAULT_DIRS = T.let(
       {
         appdir:               "/Applications",
+        appimagedir:          "~/Applications",
         keyboard_layoutdir:   "/Library/Keyboard Layouts",
         colorpickerdir:       "~/Library/ColorPickers",
         prefpanedir:          "~/Library/PreferencePanes",
@@ -49,6 +50,7 @@ def self.from_args(args)
       args = T.unsafe(args)
       new(explicit: {
         appdir:               args.appdir,
+        appimagedir:          args.appimagedir,
         keyboard_layoutdir:   args.keyboard_layoutdir,
         colorpickerdir:       args.colorpickerdir,
         prefpanedir:          args.prefpanedir,

Library/Homebrew/cask/dsl.rb

@@ -38,6 +38,7 @@ class DSL
     ORDINARY_ARTIFACT_CLASSES = [
       Artifact::Installer,
       Artifact::App,
+      Artifact::AppImage,
       Artifact::Artifact,
       Artifact::AudioUnitPlugin,
       Artifact::Binary,

Library/Homebrew/cli/parser.rb

@@ -66,6 +66,10 @@ def self.global_cask_options
             description: "Target location for Applications " \
                          "(default: `#{Cask::Config::DEFAULT_DIRS[:appdir]}`).",
           }],
+          [:flag, "--appimagedir=", {
+            description: "Target location for AppImages " \
+                         "(default: `#{Cask::Config::DEFAULT_DIRS[:appimagedir]}`).",
+          }],
           [:flag, "--keyboard-layoutdir=", {
             description: "Target location for Keyboard Layouts " \
                          "(default: `#{Cask::Config::DEFAULT_DIRS[:keyboard_layoutdir]}`).",

Library/Homebrew/extend/os/cask/installer.rb

@@ -2,3 +2,4 @@
 # frozen_string_literal: true
 
 require "extend/os/linux/cask/installer" if OS.linux?
+require "extend/os/mac/cask/installer" if OS.mac?

Library/Homebrew/extend/os/mac/cask/installer.rb

@@ -0,0 +1,30 @@
+# typed: strict
+# frozen_string_literal: true
+
+module OS
+  module Mac
+    module Cask
+      module Installer
+        extend T::Helpers
+
+        requires_ancestor { ::Cask::Installer }
+
+        sig { void }
+        def check_stanza_os_requirements
+          return if artifacts.all? { |artifact| supported_artifact?(artifact) }
+
+          raise ::Cask::CaskError, "Linux is required for this software."
+        end
+
+        private
+
+        sig { params(artifact: ::Cask::Artifact::AbstractArtifact).returns(T::Boolean) }
+        def supported_artifact?(artifact)
+          ::Cask::Artifact::LINUX_ONLY_ARTIFACTS.exclude?(artifact.class)
+        end
+      end
+    end
+  end
+end
+
+Cask::Installer.prepend(OS::Mac::Cask::Installer)