Use Dir.mktmpdir instead of shelling out to mktemp

Closes Homebrew/homebrew#37616.

Library/Homebrew/extend/fileutils.rb

@@ -1,4 +1,5 @@
-require 'fileutils'
+require "fileutils"
+require "tmpdir"
 
 # We enhance FileUtils to make our Formula code more readable.
 module FileUtils
@@ -6,24 +7,19 @@ module FileUtils
   # Create a temporary directory then yield. When the block returns,
   # recursively delete the temporary directory.
   def mktemp(prefix=name)
-    # I used /tmp rather than `mktemp -td` because that generates a directory
+    prev = pwd
-    # name with exotic characters like + in it, and these break badly written
+    tmp  = Dir.mktmpdir(prefix, HOMEBREW_TEMP)
-    # scripts that don't escape strings before trying to regexp them :(
-
-    # If the user has FileVault enabled, then we can't mv symlinks from the
-    # /tmp volume to the other volume. So we let the user override the tmp
-    # prefix if they need to.
-
-    tempd = with_system_path { `mktemp -d #{HOMEBREW_TEMP}/#{prefix}-XXXXXX` }.strip
-    raise "Failed to create sandbox" if tempd.empty?
-    prevd = pwd
-    cd(tempd)
 
     begin
-      yield
+      cd(tmp)
+
+      begin
+        yield
+      ensure
+        cd(prev)
+      end
     ensure
-      cd(prevd)
+      ignore_interrupts { rm_r(tmp) }
-      ignore_interrupts { rm_r(tempd) }
     end
   end
   module_function :mktemp