Remove memoization from uses.rb, as it doesn't result in the expected time complexity savings

Library/Homebrew/cmd/readall.rb

@@ -14,7 +14,7 @@ module Homebrew
   def readall
     if ARGV.include?("--syntax")
       scan_files = "#{HOMEBREW_LIBRARY_PATH}/**/*.rb"
-      ruby_files = Dir.glob(scan_files).reject { |file| file =~ /vendor|cask/ }
+      ruby_files = Dir.glob(scan_files).reject { |file| file =~ %r{/(vendor|cask)/} }
 
       Homebrew.failed = true unless Readall.valid_ruby_syntax?(ruby_files)
     end

Library/Homebrew/cmd/uses.rb

@@ -54,14 +54,11 @@ module Homebrew
     end
     ignores << "recommended?" if ARGV.include? "--skip-recommended"
 
-    memo = {}
     uses = formulae.select do |f|
       used_formulae.all? do |ff|
         begin
           if recursive
             deps = f.recursive_dependencies do |dependent, dep|
-              memo_key = [dependent, dep].to_s
-              next if memo[memo_key]
               if dep.recommended?
                 Dependency.prune if ignores.include?("recommended?") || dependent.build.without?(dep)
               elsif dep.optional?
@@ -75,7 +72,6 @@ module Homebrew
               if dep.is_a?(TapDependency) && !dep.tap.installed?
                 Dependency.keep_but_prune_recursive_deps
               end
-              memo[memo_key] = true
             end
 
             dep_formulae = deps.flat_map do |dep|