utils: prepare for deprecation of Utils.gzip

Library/Homebrew/test/utils_spec.rb

@@ -183,15 +183,6 @@ describe "globally-scoped helper methods" do
     expect(which_editor).to eq("vemate -w")
   end
 
-  specify "#gzip" do
-    mktmpdir do |path|
-      somefile = path/"somefile"
-      FileUtils.touch somefile
-      expect(gzip(somefile)[0].to_s).to eq("#{somefile}.gz")
-      expect(Pathname.new("#{somefile}.gz")).to exist
-    end
-  end
-
   specify "#capture_stderr" do
     err = capture_stderr do
       $stderr.print "test"

Library/Homebrew/utils.rb

@@ -11,6 +11,7 @@ require "utils/gems"
 require "utils/git"
 require "utils/git_repository"
 require "utils/github"
+require "utils/gzip"
 require "utils/inreplace"
 require "utils/link"
 require "utils/popen"
@@ -397,11 +398,10 @@ module Kernel
   end
 
   # GZips the given paths, and returns the gzipped paths.
+  # TODO: Add deprecation
+  # odeprecated "Utils.gzip" "Utils::Gzip.compress"
   def gzip(*paths)
-    paths.map do |path|
-      safe_system "gzip", path
-      Pathname.new("#{path}.gz")
-    end
+    Utils::Gzip.compress(*paths)
   end
 
   def ignore_interrupts(_opt = nil)