diff --git a/Library/Homebrew/cli/args.rb b/Library/Homebrew/cli/args.rb
index cc2f277e02..4032bb9dab 100644
--- a/Library/Homebrew/cli/args.rb
+++ b/Library/Homebrew/cli/args.rb
@@ -50,6 +50,69 @@ module Homebrew
       def passthrough
         options_only - CLI::Parser.global_options.values.map(&:first).flatten
       end
+
+      def downcased_unique_named
+        # Only lowercase names, not paths, bottle filenames or URLs
+        @downcased_unique_named ||= remaining.map do |arg|
+          if arg.include?("/") || arg.end_with?(".tar.gz") || File.exist?(arg)
+            arg
+          else
+            arg.downcase
+          end
+        end.uniq
+      end
+
+      def kegs
+        require "keg"
+        require "formula"
+        require "missing_formula"
+
+        @kegs ||= downcased_unique_named.map do |name|
+          raise UsageError if name.empty?
+
+          rack = Formulary.to_rack(name.downcase)
+
+          dirs = rack.directory? ? rack.subdirs : []
+
+          if dirs.empty?
+            if (reason = Homebrew::MissingFormula.suggest_command(name, "uninstall"))
+              $stderr.puts reason
+            end
+            raise NoSuchKegError, rack.basename
+          end
+
+          linked_keg_ref = HOMEBREW_LINKED_KEGS/rack.basename
+          opt_prefix = HOMEBREW_PREFIX/"opt/#{rack.basename}"
+
+          begin
+            if opt_prefix.symlink? && opt_prefix.directory?
+              Keg.new(opt_prefix.resolved_path)
+            elsif linked_keg_ref.symlink? && linked_keg_ref.directory?
+              Keg.new(linked_keg_ref.resolved_path)
+            elsif dirs.length == 1
+              Keg.new(dirs.first)
+            else
+              f = if name.include?("/") || File.exist?(name)
+                Formulary.factory(name)
+              else
+                Formulary.from_rack(rack)
+              end
+
+              unless (prefix = f.installed_prefix).directory?
+                raise MultipleVersionsInstalledError, rack.basename
+              end
+
+              Keg.new(prefix)
+            end
+          rescue FormulaUnavailableError
+            raise <<~EOS
+              Multiple kegs installed to #{rack}
+              However we don't know which one you refer to.
+              Please delete (with rm -rf!) all but one and then try again.
+            EOS
+          end
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cmd/link.rb b/Library/Homebrew/cmd/link.rb
index 4b45ca98ac..1697be6a6e 100644
--- a/Library/Homebrew/cmd/link.rb
+++ b/Library/Homebrew/cmd/link.rb
@@ -38,7 +38,7 @@ module Homebrew
     mode.overwrite = true if args.overwrite?
     mode.dry_run = true if args.dry_run?
 
-    ARGV.kegs.each do |keg|
+    Homebrew.args.kegs.each do |keg|
       keg_only = Formulary.keg_only?(keg.rack)
 
       if keg.linked?
diff --git a/Library/Homebrew/cmd/list.rb b/Library/Homebrew/cmd/list.rb
index a6cd43d331..8c3004aff8 100644
--- a/Library/Homebrew/cmd/list.rb
+++ b/Library/Homebrew/cmd/list.rb
@@ -73,9 +73,9 @@ module Homebrew
         safe_system "ls", *Homebrew.args.passthrough << HOMEBREW_CELLAR
       end
     elsif args.verbose? || !$stdout.tty?
-      system_command! "find", args: ARGV.kegs.map(&:to_s) + %w[-not -type d -print], print_stdout: true
+      system_command! "find", args: Homebrew.args.kegs.map(&:to_s) + %w[-not -type d -print], print_stdout: true
     else
-      ARGV.kegs.each { |keg| PrettyListing.new keg }
+      Homebrew.args.kegs.each { |keg| PrettyListing.new keg }
     end
   end
 
diff --git a/Library/Homebrew/cmd/uninstall.rb b/Library/Homebrew/cmd/uninstall.rb
index 6604665548..a508f94d92 100644
--- a/Library/Homebrew/cmd/uninstall.rb
+++ b/Library/Homebrew/cmd/uninstall.rb
@@ -38,7 +38,7 @@ module Homebrew
         [rack, rack.subdirs.map { |d| Keg.new(d) }]
       end]
     else
-      ARGV.kegs.group_by(&:rack)
+      Homebrew.args.kegs.group_by(&:rack)
     end
 
     handle_unsatisfied_dependents(kegs_by_rack)
diff --git a/Library/Homebrew/cmd/unlink.rb b/Library/Homebrew/cmd/unlink.rb
index 2e16ead6cb..98f9b3b26c 100644
--- a/Library/Homebrew/cmd/unlink.rb
+++ b/Library/Homebrew/cmd/unlink.rb
@@ -31,7 +31,7 @@ module Homebrew
     mode = OpenStruct.new
     mode.dry_run = true if args.dry_run?
 
-    ARGV.kegs.each do |keg|
+    Homebrew.args.kegs.each do |keg|
       if mode.dry_run
         puts "Would remove:"
         keg.unlink(mode)
diff --git a/Library/Homebrew/dev-cmd/linkage.rb b/Library/Homebrew/dev-cmd/linkage.rb
index cce1eb8bdb..64420fab60 100644
--- a/Library/Homebrew/dev-cmd/linkage.rb
+++ b/Library/Homebrew/dev-cmd/linkage.rb
@@ -33,10 +33,10 @@ module Homebrew
     linkage_args.parse
 
     CacheStoreDatabase.use(:linkage) do |db|
-      kegs = if ARGV.kegs.empty?
+      kegs = if Homebrew.args.kegs.empty?
         Formula.installed.map(&:opt_or_installed_prefix_keg).reject(&:nil?)
       else
-        ARGV.kegs
+        Homebrew.args.kegs
       end
       kegs.each do |keg|
         ohai "Checking #{keg.name} linkage" if kegs.size > 1
diff --git a/Library/Homebrew/extend/ARGV.rb b/Library/Homebrew/extend/ARGV.rb
index b312579b44..3d5a6d5e5e 100644
--- a/Library/Homebrew/extend/ARGV.rb
+++ b/Library/Homebrew/extend/ARGV.rb
@@ -39,58 +39,6 @@ module HomebrewArgvExtension
     downcased_unique_named.grep HOMEBREW_CASK_TAP_CASK_REGEX
   end
 
-  def kegs
-    require "keg"
-    require "formula"
-    require "missing_formula"
-    # TODO: use @instance variable to ||= cache when moving to CLI::Parser
-    downcased_unique_named.map do |name|
-      raise UsageError if name.empty?
-
-      rack = Formulary.to_rack(name.downcase)
-
-      dirs = rack.directory? ? rack.subdirs : []
-
-      if dirs.empty?
-        if (reason = Homebrew::MissingFormula.suggest_command(name, "uninstall"))
-          $stderr.puts reason
-        end
-        raise NoSuchKegError, rack.basename
-      end
-
-      linked_keg_ref = HOMEBREW_LINKED_KEGS/rack.basename
-      opt_prefix = HOMEBREW_PREFIX/"opt/#{rack.basename}"
-
-      begin
-        if opt_prefix.symlink? && opt_prefix.directory?
-          Keg.new(opt_prefix.resolved_path)
-        elsif linked_keg_ref.symlink? && linked_keg_ref.directory?
-          Keg.new(linked_keg_ref.resolved_path)
-        elsif dirs.length == 1
-          Keg.new(dirs.first)
-        else
-          f = if name.include?("/") || File.exist?(name)
-            Formulary.factory(name)
-          else
-            Formulary.from_rack(rack)
-          end
-
-          unless (prefix = f.installed_prefix).directory?
-            raise MultipleVersionsInstalledError, rack.basename
-          end
-
-          Keg.new(prefix)
-        end
-      rescue FormulaUnavailableError
-        raise <<~EOS
-          Multiple kegs installed to #{rack}
-          However we don't know which one you refer to.
-          Please delete (with rm -rf!) all but one and then try again.
-        EOS
-      end
-    end
-  end
-
   def value(name)
     arg_prefix = "--#{name}="
     flag_with_value = find { |arg| arg.start_with?(arg_prefix) }
diff --git a/Library/Homebrew/test/ARGV_spec.rb b/Library/Homebrew/test/ARGV_spec.rb
index 868240a1c3..b8ccd4d831 100644
--- a/Library/Homebrew/test/ARGV_spec.rb
+++ b/Library/Homebrew/test/ARGV_spec.rb
@@ -27,27 +27,6 @@ describe HomebrewArgvExtension do
     end
   end
 
-  describe "#kegs" do
-    context "when there are matching Kegs" do
-      before do
-        keg = HOMEBREW_CELLAR + "mxcl/10.0"
-        keg.mkpath
-      end
-
-      it "returns an array of Kegs" do
-        expect(subject.kegs.length).to eq 1
-      end
-    end
-
-    context "when there are no matching Kegs" do
-      let(:argv) { [] }
-
-      it "returns an empty array" do
-        expect(subject.kegs).to be_empty
-      end
-    end
-  end
-
   describe "#named" do
     let(:argv) { ["foo", "--debug", "-v"] }
 
diff --git a/Library/Homebrew/test/cli/parser_spec.rb b/Library/Homebrew/test/cli/parser_spec.rb
index 5d5171f57b..8a326d52a7 100644
--- a/Library/Homebrew/test/cli/parser_spec.rb
+++ b/Library/Homebrew/test/cli/parser_spec.rb
@@ -235,5 +235,22 @@ describe Homebrew::CLI::Parser do
       parser.parse(["--foo", "--bar=value", "-v", "-s", "a", "b", "cdefg"])
       expect(Homebrew.args.passthrough).to eq %w[--foo --bar=value -s]
     end
+
+    context "kegs" do
+      before do
+        keg = HOMEBREW_CELLAR + "mxcl/10.0"
+        keg.mkpath
+      end
+
+      it "when there are matching kegs returns an array of Kegs" do
+        parser.parse(["mxcl"])
+        expect(Homebrew.args.kegs.length).to eq 1
+      end
+
+      it "when there are no matching kegs returns an array of Kegs" do
+        parser.parse([])
+        expect(Homebrew.args.kegs).to be_empty
+      end
+    end
   end
 end