debug_symbols passed down to soure dir creator

The flag is now passed down to resource which creates the directory for
unpacking the source.

Library/Homebrew/formula.rb

@@ -1276,7 +1276,7 @@ class Formula
   def brew(fetch: true, keep_tmp: false, debug_symbols: false, interactive: false)
     @prefix_returns_versioned_prefix = true
     active_spec.fetch if fetch
-    stage(interactive: interactive) do |staging|
+    stage(interactive: interactive, debug_symbols: debug_symbols) do |staging|
       staging.retain! if keep_tmp || debug_symbols
 
       prepare_patches
@@ -2437,8 +2437,8 @@ class Formula
     }
   end
 
-  def stage(interactive: false)
+  def stage(interactive: false, debug_symbols: false)
-    active_spec.stage do |staging|
+    active_spec.stage(debug_symbols: debug_symbols) do |staging|
       @source_modified_time = active_spec.source_modified_time
       @buildpath = Pathname.pwd
       env_home = buildpath/".brew_home"

Library/Homebrew/mksource.rb

@@ -0,0 +1,84 @@
+# typed: false
+# frozen_string_literal: true
+
+# Performs {Formula#mktemp}'s functionality, and tracks the results.
+# Each instance is only intended to be used once.
+class Mksource
+  extend T::Sig
+
+  include FileUtils
+
+  # Path to the tmpdir used in this run, as a {Pathname}.
+  attr_reader :tmpdir
+
+  def initialize(prefix, opts = {})
+    @prefix = prefix
+    @retain = opts[:retain]
+    @quiet = false
+  end
+
+  # Instructs this {Mksource} to retain the staged files.
+  sig { void }
+  def retain!
+    @retain = true
+  end
+
+  # True if the staged temporary files should be retained.
+  def retain?
+    @retain
+  end
+
+  # Instructs this Mksource to not emit messages when retention is triggered.
+  sig { void }
+  def quiet!
+    @quiet = true
+  end
+
+  sig { returns(String) }
+  def to_s
+    "[Mksource: #{tmpdir} retain=#{@retain} quiet=#{@quiet}]"
+  end
+
+  def run
+    @tmpdir = Pathname.new(Dir.mktmpdir("#{@prefix.tr "@", "AT"}-", HOMEBREW_TEMP))
+
+    # Make sure files inside the temporary directory have the same group as the
+    # brew instance.
+    #
+    # Reference from `man 2 open`
+    # > When a new file is created, it is given the group of the directory which
+    # contains it.
+    group_id = if HOMEBREW_BREW_FILE.grpowned?
+      HOMEBREW_BREW_FILE.stat.gid
+    else
+      Process.gid
+    end
+    begin
+      chown(nil, group_id, tmpdir)
+    rescue Errno::EPERM
+      opoo "Failed setting group \"#{Etc.getgrgid(group_id).name}\" on #{tmpdir}"
+    end
+
+    begin
+      Dir.chdir(tmpdir) { yield self }
+    ensure
+      ignore_interrupts { chmod_rm_rf(tmpdir) } unless retain?
+    end
+  ensure
+    ohai "Temporary files retained at:", @tmpdir.to_s if retain? && !@tmpdir.nil? && !@quiet
+  end
+
+  private
+
+  def chmod_rm_rf(path)
+    if path.directory? && !path.symlink?
+      chmod("u+rw", path) if path.owned? # Need permissions in order to see the contents
+      path.children.each { |child| chmod_rm_rf(child) }
+      rmdir(path)
+    else
+      rm_f(path)
+    end
+  rescue
+    nil # Just skip this directory.
+  end
+end

Library/Homebrew/resource.rb

@@ -5,6 +5,7 @@ require "download_strategy"
 require "checksum"
 require "version"
 require "mktemp"
+require "mksource"
 require "livecheck"
 require "extend/on_system"
 
@@ -89,14 +90,14 @@ class Resource
   # dir using {Mktemp} so that works with all subtypes.
   #
   # @api public
-  def stage(target = nil, &block)
+  def stage(target = nil, debug_symbols: false, &block)
     raise ArgumentError, "target directory or block is required" if !target && block.blank?
 
     prepare_patches
     fetch_patches(skip_downloaded: true)
     fetch unless downloaded?
 
-    unpack(target, &block)
+    unpack(target, debug_symbols: debug_symbols, &block)
   end
 
   def prepare_patches
@@ -120,9 +121,9 @@ class Resource
   # If block is given, yield to that block with `|stage|`, where stage
   # is a {ResourceStageContext}.
   # A target or a block must be given, but not both.
-  def unpack(target = nil)
+  def unpack(target = nil, debug_symbols: false)
     current_working_directory = Pathname.pwd
-    mktemp(download_name) do |staging|
+    stage_resource(download_name, debug_symbols: debug_symbols) do |staging|
       downloader.stage do
         @source_modified_time = downloader.source_modified_time
         apply_patches
@@ -235,8 +236,8 @@ class Resource
 
   protected
 
-  def mktemp(prefix, &block)
+  def stage_resource(prefix, debug_symbols: false, &block)
-    Mktemp.new(prefix).run(&block)
+    debug_symbols ? Mksource.new(prefix).run(&block) : Mktemp.new(prefix).run(&block)
   end
 
   private