Consistent cask installed checks across all code paths

Several code paths that determine whether a cask is installed were using
different heuristics (raw `ls`, directory existence, `Caskroom.casks`),
which could disagree with `Cask#installed?`. This consolidates them all
to use `.metadata` directory presence as the source of truth.

- Add `Cask::Caskroom.cask_installed?` utility method
- Update `Caskroom.any_casks_installed?` to check `.metadata`
- Update `list.sh` bash fast path to check `.metadata`
- Update `cmd/list.rb` to use `Caskroom.casks` in all code paths
- Update `cmd/update-report.rb` to delegate to `Caskroom.cask_installed?`
- Add unit tests for consistency

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: koddsson

Library/Homebrew/cask/caskroom.rb

@@ -31,9 +31,16 @@ def self.tokens
       paths.map { |path| path.basename.to_s }
     end
 
+    # Check if a cask with the given token is installed, consistent with {Cask#installed?}.
+    # Checks for an installed caskfile inside `.metadata/<version>/<timestamp>/Casks/`.
+    sig { params(token: String).returns(T::Boolean) }
+    def self.cask_installed?(token)
+      Pathname.glob(path/token/".metadata"/"*"/"*"/"Casks"/"*.{rb,json}").any?
+    end
+
     sig { returns(T::Boolean) }
     def self.any_casks_installed?
-      paths.any?
+      paths.any? { |p| Pathname.glob(p/".metadata"/"*"/"*"/"Casks"/"*.{rb,json}").any? }
     end
 
     sig { void }

Library/Homebrew/cmd/list.rb

@@ -162,9 +162,23 @@ def run
             system_command! "ls", args: [*ls_args, HOMEBREW_CELLAR], print_stdout: true
             puts if $stdout.tty? && !args.formula?
           end
-          if !args.formula? && Cask::Caskroom.any_casks_installed?
-            ohai "Casks" if $stdout.tty? && !args.cask?
-            system_command! "ls", args: [*ls_args, Cask::Caskroom.path], print_stdout: true
+          unless args.formula?
+            casks = Cask::Caskroom.casks
+            if args.t?
+              casks.sort_by! { |c| c.install_time || Time.at(0) }.reverse!
+            else
+              casks.sort_by!(&:token)
+            end
+            casks.reverse! if args.r?
+            cask_names = casks.map(&:token)
+            if cask_names.present?
+              ohai "Casks" if $stdout.tty? && !args.cask?
+              if args.public_send(:"1?") || !$stdout.tty?
+                puts cask_names
+              else
+                puts Formatter.columns(cask_names)
+              end
+            end
           end
         else
           kegs, casks = args.named.to_kegs_to_casks
@@ -215,15 +229,7 @@ def filtered_list
       sig { void }
       def list_casks
         casks = if args.no_named?
-          cask_paths = Cask::Caskroom.path.children.reject(&:file?).map do |path|
-            if path.symlink?
-              real_path = path.realpath
-              real_path.basename.to_s
-            else
-              path.basename.to_s
-            end
-          end.uniq.sort
-          cask_paths.map { |name| Cask::CaskLoader.load(name) }
+          Cask::Caskroom.casks
         else
           filtered_args = args.named.dup.delete_if do |n|
             Homebrew.failed = true unless Cask::Caskroom.path.join(n).exist?

Library/Homebrew/cmd/update-report.rb

@@ -938,7 +938,7 @@ def installed?(formula)
 
   sig { params(cask: String).returns(T::Boolean) }
   def cask_installed?(cask)
-    (Cask::Caskroom.path/cask).directory?
+    Cask::Caskroom.cask_installed?(cask)
   end
 
   sig { returns(T::Array[T.untyped]) }

Library/Homebrew/list.sh

@@ -71,16 +71,28 @@ homebrew-list() {
 
   if [[ -z "${formula}" && -d "${HOMEBREW_CASKROOM}" ]]
   then
-    if [[ -n "${tty}" && -z "${cask}" ]]
-    then
-      ohai "Casks"
-    fi
+    # Filter to only casks with installed metadata, consistent with
+    # Cask::Caskroom.cask_installed? and Cask#installed?.
+    local installed_cask_names=()
+    for dir in "${HOMEBREW_CASKROOM}"/*/
+    do
+      [[ -d "${dir}.metadata" ]] && installed_cask_names+=("$(basename "${dir}")")
+    done
 
-    local cask_output
-    cask_output="$(/usr/bin/env "${ls_env[@]}" ls "${ls_args[@]}" "${HOMEBREW_CASKROOM}")" || exit 1
-    if [[ -n "${cask_output}" ]]
+    if ((${#installed_cask_names[@]} > 0))
     then
-      echo "${cask_output}"
+      if [[ -n "${tty}" && -z "${cask}" ]]
+      then
+        ohai "Casks"
+      fi
+
+      local cask_output
+      # Use ls -d on filtered names so formatting flags (-1/-l/-r/-t) are honoured
+      cask_output="$(cd "${HOMEBREW_CASKROOM}" && /usr/bin/env "${ls_env[@]}" ls "${ls_args[@]}" -d -- "${installed_cask_names[@]}")" || exit 1
+      if [[ -n "${cask_output}" ]]
+      then
+        echo "${cask_output}"
+      fi
     fi
 
     return 0

Library/Homebrew/test/cask/caskroom_spec.rb

@@ -0,0 +1,76 @@
+# typed: false
+# frozen_string_literal: true
+
+require "cask/caskroom"
+
+RSpec.describe Cask::Caskroom do
+  describe ".cask_installed?" do
+    it "returns true when a cask has an installed caskfile" do
+      Dir.mktmpdir do |dir|
+        allow(described_class).to receive(:path).and_return(Pathname(dir))
+        casks_dir = (Pathname(dir)/"test-cask"/".metadata"/"1.0"/"0"/"Casks")
+        casks_dir.mkpath
+        FileUtils.touch casks_dir/"test-cask.rb"
+
+        expect(described_class.cask_installed?("test-cask")).to be true
+      end
+    end
+
+    it "returns false when .metadata exists but has no caskfile" do
+      Dir.mktmpdir do |dir|
+        allow(described_class).to receive(:path).and_return(Pathname(dir))
+        (Pathname(dir)/"test-cask"/".metadata"/"1.0"/"0"/"Casks").mkpath
+
+        expect(described_class.cask_installed?("test-cask")).to be false
+      end
+    end
+
+    it "returns false when a cask directory has no .metadata" do
+      Dir.mktmpdir do |dir|
+        allow(described_class).to receive(:path).and_return(Pathname(dir))
+        (Pathname(dir)/"test-cask"/"1.0").mkpath
+
+        expect(described_class.cask_installed?("test-cask")).to be false
+      end
+    end
+
+    it "returns false when a cask directory does not exist" do
+      Dir.mktmpdir do |dir|
+        allow(described_class).to receive(:path).and_return(Pathname(dir))
+
+        expect(described_class.cask_installed?("nonexistent-cask")).to be false
+      end
+    end
+  end
+
+  describe ".any_casks_installed?" do
+    it "returns false when caskroom is empty" do
+      Dir.mktmpdir do |dir|
+        allow(described_class).to receive(:path).and_return(Pathname(dir))
+
+        expect(described_class.any_casks_installed?).to be false
+      end
+    end
+
+    it "returns false when only bare directories exist" do
+      Dir.mktmpdir do |dir|
+        allow(described_class).to receive(:path).and_return(Pathname(dir))
+        (Pathname(dir)/"bare-cask"/"1.0").mkpath
+
+        expect(described_class.any_casks_installed?).to be false
+      end
+    end
+
+    it "returns true when at least one cask has an installed caskfile" do
+      Dir.mktmpdir do |dir|
+        allow(described_class).to receive(:path).and_return(Pathname(dir))
+        (Pathname(dir)/"bare-cask"/"1.0").mkpath
+        casks_dir = (Pathname(dir)/"installed-cask"/".metadata"/"1.0"/"0"/"Casks")
+        casks_dir.mkpath
+        FileUtils.touch casks_dir/"installed-cask.rb"
+
+        expect(described_class.any_casks_installed?).to be true
+      end
+    end
+  end
+end

Library/Homebrew/test/cmd/list_spec.rb

@@ -25,4 +25,19 @@
       .to be_a_success
       .and not_to_output.to_stderr
   end
+
+  describe "cask listing" do
+    it "lists only casks returned by Caskroom.casks" do
+      installed_cask = instance_double(Cask::Cask, token: "installed-cask", install_time: Time.now)
+      expect(Cask::Caskroom).to receive(:casks).and_return([installed_cask])
+      expect(Cask::List).to receive(:list_casks).with(
+        installed_cask,
+        one:       false,
+        full_name: false,
+        versions:  true,
+      )
+
+      described_class.new(["--cask", "--versions"]).run
+    end
+  end
 end

Library/Homebrew/test/cmd/update-report_spec.rb

@@ -280,5 +280,12 @@ def perform_update(fixture_name = "")
       allow(Cask::Caskroom).to receive(:casks).and_return([])
       expect { hub.dump }.not_to output.to_stdout
     end
+
+    describe "#cask_installed?" do
+      it "delegates to Cask::Caskroom.cask_installed?" do
+        expect(Cask::Caskroom).to receive(:cask_installed?).with("test-cask").and_return(true)
+        expect(hub.send(:cask_installed?, "test-cask")).to be true
+      end
+    end
   end
 end