Don't remove cask directories when upgrading.

Fixes Homebrew/homebrew-cask#102721.

Library/Homebrew/cask/artifact/moved.rb

@@ -34,39 +34,50 @@ module Cask
 
       private
 
-      def move(adopt: false, force: false, verbose: false, command: nil, **options)
+      def move(adopt: false, force: false, verbose: false, upgrade: false, command: nil, **options)
         unless source.exist?
           raise CaskError, "It seems the #{self.class.english_name} source '#{source}' is not there."
         end
 
         if Utils.path_occupied?(target)
-          if adopt
+          if upgrade && target.directory? && target.children.empty?
-            ohai "Adopting existing #{self.class.english_name} at '#{target}'"
+            # An upgrade removed the directory contents but left the directory itself (see below).
-            same = command.run(
+            unless source.directory?
-              "/usr/bin/diff",
+              if target.parent.writable? && !force
-              args:         ["--recursive", "--brief", source, target],
+                target.rmdir
-              verbose:      verbose,
+              else
-              print_stdout: verbose,
+                Utils.gain_permissions_remove(target, command: command)
-            ).success?
+              end
+            end
+          else
+            if adopt
+              ohai "Adopting existing #{self.class.english_name} at '#{target}'"
+              same = command.run(
+                "/usr/bin/diff",
+                args:         ["--recursive", "--brief", source, target],
+                verbose:      verbose,
+                print_stdout: verbose,
+              ).success?
 
-            unless same
+              unless same
-              raise CaskError,
+                raise CaskError,
-                    "It seems the existing #{self.class.english_name} is different from " \
+                      "It seems the existing #{self.class.english_name} is different from " \
-                    "the one being installed."
+                      "the one being installed."
+              end
+
+              # Remove the source as we don't need to move it to the target location
+              source.rmtree
+
+              return post_move(command)
             end
 
-            # Remove the source as we don't need to move it to the target location
+            message = "It seems there is already #{self.class.english_article} " \
-            source.rmtree
+                      "#{self.class.english_name} at '#{target}'"
+            raise CaskError, "#{message}." unless force
 
-            return post_move(command)
+            opoo "#{message}; overwriting."
+            delete(target, force: force, command: command, **options)
           end
-
-          message = "It seems there is already #{self.class.english_article} " \
-                    "#{self.class.english_name} at '#{target}'"
-          raise CaskError, "#{message}." unless force
-
-          opoo "#{message}; overwriting."
-          delete(target, force: force, command: command, **options)
         end
 
         ohai "Moving #{self.class.english_name} '#{source.basename}' to '#{target}'"
@@ -79,7 +90,16 @@ module Cask
           end
         end
 
-        if target.dirname.writable?
+        if target.directory?
+          if target.writable?
+            source.children.each { |child| FileUtils.move(child, target + child.basename) }
+          else
+            command.run!("/bin/cp", args: ["-pR", "#{source}/*", "#{source}/.*", "#{target}/"],
+                                    sudo: true)
+          end
+          # TODO: copy extended attributes
+          source.rmtree
+        elsif target.dirname.writable?
           FileUtils.move(source, target)
         else
           # default sudo user isn't necessarily able to write to Homebrew's locations
@@ -125,13 +145,23 @@ module Cask
         delete(target, force: force, command: command, **options)
       end
 
-      def delete(target, force: false, command: nil, **_)
+      def delete(target, force: false, upgrade: false, command: nil, **_)
         ohai "Removing #{self.class.english_name} '#{target}'"
         raise CaskError, "Cannot remove undeletable #{self.class.english_name}." if MacOS.undeletable?(target)
 
         return unless Utils.path_occupied?(target)
 
-        if target.parent.writable? && !force
+        if upgrade && target.directory?
+          # If an app folder is deleted, macOS considers the app uninstalled and removes some data.
+          # Remove only the contents to handle this case.
+          target.children.each do |child|
+            if target.writable? && !force
+              child.rmtree
+            else
+              Utils.gain_permissions_remove(child, command: command)
+            end
+          end
+        elsif target.parent.writable? && !force
           target.rmtree
         else
           Utils.gain_permissions_remove(target, command: command)

Library/Homebrew/cask/installer.rb

@@ -234,7 +234,7 @@ on_request: true)
 
         next if artifact.is_a?(Artifact::Binary) && !binaries?
 
-        artifact.install_phase(command: @command, verbose: verbose?, adopt: adopt?, force: force?)
+        artifact.install_phase(command: @command, verbose: verbose?, adopt: adopt?, force: force?, upgrade: upgrade?)
         already_installed_artifacts.unshift(artifact)
       end