formula: refactor outdated_kegs logic.

- Use the `Formula.cache` and `Cacheable` rather than rolling our own.
- Use keyword arguments instead of `options = {}`
- Improve readability in general

Library/Homebrew/formula.rb

@@ -495,22 +495,18 @@ class Formula
     prefix(head_version) if head_version
   end
 
-  def head_version_outdated?(version, options = {})
+  def head_version_outdated?(version, fetch_head: false)
     tab = Tab.for_keg(prefix(version))
 
     return true if tab.version_scheme < version_scheme
     return true if stable && tab.stable_version && tab.stable_version < stable.version
     return true if devel && tab.devel_version && tab.devel_version < devel.version
-
+    return false unless fetch_head
-    if options[:fetch_head]
     return false unless head&.downloader.is_a?(VCSDownloadStrategy)
 
     downloader = head.downloader
     downloader.shutup! unless ARGV.verbose?
     downloader.commit_outdated?(version.version.commit)
-    else
-      false
-    end
   end
 
   # The latest prefix for this formula. Checks for {#head}, then {#devel}
@@ -1173,17 +1169,14 @@ class Formula
   end
 
   # @private
-  def outdated_kegs(options = {})
+  def outdated_kegs(fetch_head: false)
-    @outdated_kegs ||= Hash.new do |cache, key|
     raise Migrator::MigrationNeededError, self if migration_needed?
 
-      cache[key] = _outdated_kegs(key)
+    cache_key = "#{name}-#{fetch_head}"
-    end
+    Formula.cache[:outdated_kegs] ||= {}
-    @outdated_kegs[options]
+    Formula.cache[:outdated_kegs][cache_key] ||= begin
-  end
-
-  def _outdated_kegs(options = {})
       all_kegs = []
+      current_version = false
 
       installed_kegs.each do |keg|
         all_kegs << keg
@@ -1197,21 +1190,22 @@ class Formula
         # don't consider this keg current if there's a newer formula available
         next if follow_installed_alias? && new_formula_available?
 
-      return [] # this keg is the current version of the formula, so it's not outdated
+        # this keg is the current version of the formula, so it's not outdated
+        current_version = true
+        break
       end
 
-    # Even if this formula hasn't been installed, there may be installations
+      if current_version
-    # of other formulae which used to be targets of the alias currently
+        []
-    # targetting this formula. These should be counted as outdated versions.
+      elsif (head_version = latest_head_version) &&
-    all_kegs.concat old_installed_formulae.flat_map(&:installed_kegs)
+            !head_version_outdated?(head_version, fetch_head: fetch_head)
-
-    head_version = latest_head_version
-    if head_version && !head_version_outdated?(head_version, options)
         []
       else
+        all_kegs += old_installed_formulae.flat_map(&:installed_kegs)
         all_kegs.sort_by(&:version)
       end
     end
+  end
 
   def new_formula_available?
     installed_alias_target_changed? && !latest_formula.installed?
@@ -1257,8 +1251,8 @@ class Formula
   end
 
   # @private
-  def outdated?(options = {})
+  def outdated?(fetch_head: false)
-    !outdated_kegs(options).empty?
+    !outdated_kegs(fetch_head: fetch_head).empty?
   rescue Migrator::MigrationNeededError
     true
   end

Library/Homebrew/test/formula_spec.rb

@@ -1091,10 +1091,6 @@ describe Formula do
       tab
     end
 
-    def reset_outdated_kegs
-      f.instance_variable_set(:@outdated_kegs, nil)
-    end
-
     example "greater different tap installed" do
       setup_tab_for_prefix(greater_prefix, tap: "user/repo")
       expect(f.outdated_kegs).to be_empty
@@ -1208,7 +1204,7 @@ describe Formula do
       expect(f.outdated_kegs).to be_empty
 
       setup_tab_for_prefix(greater_prefix, tap: "homebrew/core")
-      reset_outdated_kegs
+      described_class.clear_cache
 
       expect(f.outdated_kegs).to be_empty
     end
@@ -1220,12 +1216,12 @@ describe Formula do
 
       setup_tab_for_prefix(outdated_prefix)
       setup_tab_for_prefix(extra_outdated_prefix, tap: "homebrew/core")
-      reset_outdated_kegs
+      described_class.clear_cache
 
       expect(f.outdated_kegs).not_to be_empty
 
       setup_tab_for_prefix(outdated_prefix, tap: "user/repo")
-      reset_outdated_kegs
+      described_class.clear_cache
 
       expect(f.outdated_kegs).not_to be_empty
     end
@@ -1237,7 +1233,7 @@ describe Formula do
       expect(f.outdated_kegs).to be_empty
 
       setup_tab_for_prefix(same_prefix, tap: "user/repo")
-      reset_outdated_kegs
+      described_class.clear_cache
 
       expect(f.outdated_kegs).to be_empty
     end
@@ -1249,7 +1245,7 @@ describe Formula do
 
       tab.source["versions"] = { "stable" => f.version.to_s }
       tab.write
-      reset_outdated_kegs
+      described_class.clear_cache
 
       expect(f.outdated_kegs).to be_empty
     end
@@ -1288,15 +1284,15 @@ describe Formula do
 
         tab_a.source["versions"] = { "stable" => f.version.to_s }
         tab_a.write
-        reset_outdated_kegs
+        described_class.clear_cache
         expect(f.outdated_kegs(fetch_head: true)).not_to be_empty
 
         head_prefix_a.rmtree
-        reset_outdated_kegs
+        described_class.clear_cache
         expect(f.outdated_kegs(fetch_head: true)).not_to be_empty
 
         setup_tab_for_prefix(head_prefix_c, source_modified_time: 1)
-        reset_outdated_kegs
+        described_class.clear_cache
         expect(f.outdated_kegs(fetch_head: true)).to be_empty
       ensure
         testball_repo.rmtree if testball_repo.exist?
@@ -1348,13 +1344,13 @@ describe Formula do
         setup_tab_for_prefix(prefix_b, versions: { "stable" => "2.14", "version_scheme" => 2 })
 
         expect(f.outdated_kegs).not_to be_empty
-        reset_outdated_kegs
+        described_class.clear_cache
 
         prefix_c = HOMEBREW_CELLAR/"testball/20141009"
         setup_tab_for_prefix(prefix_c, versions: { "stable" => "20141009", "version_scheme" => 3 })
 
         expect(f.outdated_kegs).not_to be_empty
-        reset_outdated_kegs
+        described_class.clear_cache
 
         prefix_d = HOMEBREW_CELLAR/"testball/20141011"
         setup_tab_for_prefix(prefix_d, versions: { "stable" => "20141009", "version_scheme" => 3 })
@@ -1377,7 +1373,7 @@ describe Formula do
         setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0", "version_scheme" => 1 })
         expect(f.outdated_kegs).not_to be_empty
 
-        reset_outdated_kegs
+        described_class.clear_cache
         head_prefix.rmtree
 
         setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0", "version_scheme" => 2 })