Utils::Cp: Drop special case for coreutils cp

As per review feedback:

https://github.com/Homebrew/brew/pull/17373#issuecomment-2132673915

Library/Homebrew/test/formula_installer_bottle_spec.rb

@@ -21,8 +21,6 @@ RSpec.describe FormulaInstaller do
     expect(formula).to be_bottled
     expect(formula).to pour_bottle
 
-    stub_formula_loader formula("coreutils") { url "coreutils-1.0" }
-    stub_formula_loader formula("uutils-coreutils") { url "uutils-coreutils-1.0" }
     stub_formula_loader formula("gcc") { url "gcc-1.0" }
     stub_formula_loader formula("glibc") { url "glibc-1.0" }
     stub_formula_loader formula

Library/Homebrew/utils/cp.rb

@@ -17,7 +17,11 @@ module Utils
         ).returns(SystemCommand::Result)
       }
       def copy(source, target, sudo: false, verbose: false, command: SystemCommand)
-        command.run! executable, args: ["-p", *extra_flags, *source, target], sudo:, verbose:
+        # On macOS, `cp -p` guarantees to preserve extended attributes (including quarantine
+        # information) in addition to file mode. Other implementations like coreutils does not
+        # necessarily guarantee the same behavior, but that is fine because we don't really need to
+        # preserve extended attributes except when copying Cask artifacts.
+        command.run! "cp", args: ["-p", *extra_flags, *source, target], sudo:, verbose:
       end
 
       sig {
@@ -30,78 +34,26 @@ module Utils
         ).returns(SystemCommand::Result)
       }
       def copy_recursive(source, target, sudo: false, verbose: false, command: SystemCommand)
-        command.run! executable, args: ["-pR", *extra_flags, *source, target], sudo:, verbose:
+        command.run! "cp", args: ["-pR", *extra_flags, *source, target], sudo:, verbose:
       end
 
       private
 
-      GCP = (HOMEBREW_PREFIX/"opt/coreutils/libexec/gnubin/cp").freeze
+      # Use the lightweight `clonefile(2)` syscall if applicable.
-      UCP = (HOMEBREW_PREFIX/"opt/uutils-coreutils/libexec/uubin/cp").freeze
+      MACOS_FLAGS = ["-c"].freeze
-
-      sig { returns(T.any(String, Pathname)) }
-      def executable
-        case type
-        when :macos
-          Pathname("/bin/cp")
-        when :coreutils
-          GCP
-        when :uutils
-          UCP
-        else
-          "cp"
-        end
-      end
-
-      MACOS_FLAGS = [
-        # Perform a lightweight copy-on-write clone if applicable.
-        "-c",
-      ].freeze
-      GNU_FLAGS = [
-        # Unlike BSD cp, `gcp -p` doesn't guarantee to preserve extended attributes, including
-        # quarantine information on macOS.
-        "--preserve=all",
-        "--no-preserve=links",
-        # Equivalent to `-c` on macOS.
-        "--reflink=auto",
-      ].freeze
       GENERIC_FLAGS = [].freeze
 
       sig { returns(T::Array[String]) }
       def extra_flags
-        case type
+        # The `cp` command on older macOS versions also had the `-c` option, but before Sonoma, the
-        when :macos
+        # command would fail if the `clonefile` syscall isn't applicable (the underlying filesystem
+        # doesn't support the feature or the source and the target are on different filesystems).
+        if MacOS.version >= :sonoma
           MACOS_FLAGS
-        when :coreutils, :uutils
-          GNU_FLAGS
         else
           GENERIC_FLAGS
         end
       end
-
-      sig { returns(T.nilable(Symbol)) }
-      def type
-        return @type if defined?(@type)
-
-        # The `cp` command on some older macOS versions also had the `-c` option, but before Sonoma,
-        # the command would fail if the `clonefile` syscall isn't applicable (the underlying
-        # filesystem doesn't support the feature or the source and the target are on different
-        # filesystems).
-        return @type = :macos if MacOS.version >= :sonoma
-
-        {
-          coreutils: "coreutils",
-          uutils:    "uutils-coreutils",
-        }.each do |type, formula|
-          begin
-            formula = Formula[formula]
-          rescue FormulaUnavailableError
-            next
-          end
-          return @type = type if formula.optlinked?
-        end
-
-        @type = nil
-      end
     end
   end
 end