upgrade, outdated: follow alias changes

6 files changed, 188 insertions, 56 deletions

diff --git a/Library/Homebrew/cmd/outdated.rb b/Library/Homebrew/cmd/outdated.rb
index 7afa41df4..f9739cd7a 100644
--- a/Library/Homebrew/cmd/outdated.rb
+++ b/Library/Homebrew/cmd/outdated.rb
@@ -43,15 +43,26 @@ module Homebrew
 
     outdated_formulae.each do |f|
       if verbose
-        outdated_versions = f.outdated_versions(fetch_head: fetch_head)
-        current_version = if f.head? && outdated_versions.any? { |v| v.to_s == f.pkg_version.to_s }
+        outdated_kegs = f.outdated_kegs(fetch_head: fetch_head)
+
+        current_version = if f.alias_changed?
+          latest = f.latest_formula
+          "#{latest.name} (#{latest.pkg_version})"
+        elsif f.head? && outdated_kegs.any? { |k| k.version.to_s == f.pkg_version.to_s }
+          # There is a newer HEAD but the version number has not changed.
           "latest HEAD"
         else
           f.pkg_version.to_s
         end
-        puts "#{f.full_name} (#{outdated_versions.join(", ")}) < #{current_version}"
+
+        outdated_versions = outdated_kegs.
+          group_by(&:name).
+          sort_by(&:first).
+          map { |name, kegs| "#{name} (#{kegs.map(&:version) * ", "})" } * ", "
+
+        puts "#{outdated_versions} < #{current_version}"
       else
-        puts f.full_name
+        puts f.full_installed_specified_name
       end
     end
   end
@@ -62,7 +73,7 @@ module Homebrew
     outdated_formulae = formulae.select { |f| f.outdated?(fetch_head: fetch_head) }
 
     outdated = outdated_formulae.each do |f|
-      outdated_versions = f.outdated_versions(fetch_head: fetch_head)
+      outdated_versions = f.outdated_kegs(fetch_head: fetch_head).map(&:version)
       current_version = if f.head? && outdated_versions.any? { |v| v.to_s == f.pkg_version.to_s }
         "HEAD"
       else
diff --git a/Library/Homebrew/cmd/upgrade.rb b/Library/Homebrew/cmd/upgrade.rb
index 6968fbda8..c56a73384 100644
--- a/Library/Homebrew/cmd/upgrade.rb
+++ b/Library/Homebrew/cmd/upgrade.rb
@@ -37,10 +37,10 @@ module Homebrew
       (ARGV.resolved_formulae - outdated).each do |f|
         versions = f.installed_kegs.map(&:version)
         if versions.empty?
-          onoe "#{f.full_name} not installed"
+          onoe "#{f.full_specified_name} not installed"
         else
           version = versions.max
-          onoe "#{f.full_name} #{version} already installed"
+          onoe "#{f.full_specified_name} #{version} already installed"
         end
       end
       exit 1 if outdated.empty?
@@ -51,19 +51,21 @@ module Homebrew
       outdated -= pinned
     end
 
-    if outdated.empty?
+    formulae_to_install = outdated.map(&:latest_formula)
+
+    if formulae_to_install.empty?
       oh1 "No packages to upgrade"
     else
-      oh1 "Upgrading #{outdated.length} outdated package#{plural(outdated.length)}, with result:"
-      puts outdated.map { |f| "#{f.full_name} #{f.pkg_version}" } * ", "
+      oh1 "Upgrading #{formulae_to_install.length} outdated package#{plural(formulae_to_install.length)}, with result:"
+      puts formulae_to_install.map { |f| "#{f.full_specified_name} #{f.pkg_version}" } * ", "
     end
 
     unless upgrade_pinned? || pinned.empty?
       oh1 "Not upgrading #{pinned.length} pinned package#{plural(pinned.length)}:"
-      puts pinned.map { |f| "#{f.full_name} #{f.pkg_version}" } * ", "
+      puts pinned.map { |f| "#{f.full_specified_name} #{f.pkg_version}" } * ", "
     end
 
-    outdated.each do |f|
+    formulae_to_install.each do |f|
       upgrade_formula(f)
       next unless ARGV.include?("--cleanup")
       next unless f.installed?
@@ -76,7 +78,11 @@ module Homebrew
   end
 
   def upgrade_formula(f)
-    outdated_keg = Keg.new(f.linked_keg.resolved_path) if f.linked_keg.directory?
+    formulae_maybe_with_kegs = [f] + f.old_installed_formulae
+    outdated_kegs = formulae_maybe_with_kegs.
+      map(&:linked_keg).
+      select(&:directory?).
+      map { |k| Keg.new(k.resolved_path) }
 
     fi = FormulaInstaller.new(f)
     fi.options             = f.build.used_options
@@ -87,12 +93,12 @@ module Homebrew
     fi.debug               = ARGV.debug?
     fi.prelude
 
-    oh1 "Upgrading #{f.full_name}"
+    oh1 "Upgrading #{f.full_specified_name}"
 
     # first we unlink the currently active keg for this formula otherwise it is
     # possible for the existing build to interfere with the build we are about to
     # do! Seriously, it happens!
-    outdated_keg.unlink if outdated_keg
+    outdated_kegs.each(&:unlink)
 
     fi.install
     fi.finish
@@ -117,7 +123,7 @@ module Homebrew
   ensure
     # restore previous installation state if build failed
     begin
-      outdated_keg.link if outdated_keg && !f.installed?
+      outdated_kegs.each(&:link) if !f.installed?
     rescue
       nil
     end
diff --git a/Library/Homebrew/extend/ARGV.rb b/Library/Homebrew/extend/ARGV.rb
index 63e46a1e2..d9f599877 100644
--- a/Library/Homebrew/extend/ARGV.rb
+++ b/Library/Homebrew/extend/ARGV.rb
@@ -37,11 +37,23 @@ module HomebrewArgvExtension
             f.version.update_commit(k.version.version.commit) if k.version.head?
           end
         end
-        f
       else
         rack = Formulary.to_rack(name)
-        Formulary.from_rack(rack, spec(nil))
+        alias_path = Formulary.factory(name).alias_path
+        f = Formulary.from_rack(rack, spec(nil), alias_path: alias_path)
       end
+
+      # If this formula was installed with an alias that has since changed,
+      # then it was specified explicitly in ARGV. (Using the alias would
+      # instead have found the new formula.)
+      #
+      # Because of this, the user is referring to this specific formula,
+      # not any formula targetted by the same alias, so in this context
+      # the formula shouldn't be considered outdated if the alias used to
+      # install it has changed.
+      f.follow_installed_alias = false
+
+      f
     end
   end
 
diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index f2da6fbc8..41ddda307 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -60,16 +60,24 @@ class Formula
   # e.g. `this-formula`
   attr_reader :name
 
-  # The name that was used to identify this {Formula}.
-  # Could be the name of the {Formula}, or an alias.
-  # e.g. `another-name-for-this-formula`
+  # The path to the alias that was used to identify this {Formula}.
+  # e.g. `/usr/local/Library/Taps/homebrew/homebrew-core/Aliases/another-name-for-this-formula`
   attr_reader :alias_path
 
+  # The name of the alias that was used to identify this {Formula}.
+  # e.g. `another-name-for-this-formula`
+  attr_reader :alias_name
+
   # The fully-qualified name of this {Formula}.
   # For core formula it's the same as {#name}.
   # e.g. `homebrew/tap-name/this-formula`
   attr_reader :full_name
 
+  # The fully-qualified alias referring to this {Formula}.
+  # For core formula it's the same as {#alias_name}.
+  # e.g. `homebrew/tap-name/another-name-for-this-formula`
+  attr_reader :full_alias_name
+
   # The full path to this {Formula}.
   # e.g. `/usr/local/Library/Taps/homebrew/homebrew-core/Formula/this-formula.rb`
   attr_reader :path
@@ -149,25 +157,31 @@ class Formula
   # @return [BuildOptions]
   attr_accessor :build
 
+  # A {Boolean} indicating whether this formula should be considered outdated
+  # if the target of the alias it was installed with has since changed.
+  # Defaults to true.
+  # @return [Boolean]
+  attr_accessor :follow_installed_alias
+  alias follow_installed_alias? follow_installed_alias
+
   # @private
   def initialize(name, path, spec, alias_path: nil)
     @name = name
     @path = path
     @alias_path = alias_path
+    @alias_name = File.basename(alias_path) if alias_path
     @revision = self.class.revision || 0
     @version_scheme = self.class.version_scheme || 0
 
-    if path == Formulary.core_path(name)
-      @tap = CoreTap.instance
-      @full_name = name
+    @tap = if path == Formulary.core_path(name)
+      CoreTap.instance
     elsif path.to_s =~ HOMEBREW_TAP_PATH_REGEX
-      @tap = Tap.fetch($1, $2)
-      @full_name = "#{@tap}/#{name}"
-    else
-      @tap = nil
-      @full_name = name
+      Tap.fetch($1, $2)
     end
 
+    @full_name = get_full_name(name)
+    @full_alias_name = get_full_name(@alias_name)
+
     set_spec :stable
     set_spec :devel
     set_spec :head
@@ -183,6 +197,7 @@ class Formula
     validate_attributes!
     @build = active_spec.build
     @pin = FormulaPin.new(self)
+    @follow_installed_alias = true
   end
 
   # @private
@@ -197,6 +212,16 @@ class Formula
 
   private
 
+  # Allow full name logic to be re-used between names, aliases,
+  # and installed aliases.
+  def get_full_name(name)
+    if name.nil? || @tap.nil? || @tap.core_tap?
+      name
+    else
+      "#{@tap}/#{name}"
+    end
+  end
+
   def set_spec(name)
     spec = self.class.send(name)
     if spec.url
@@ -236,11 +261,39 @@ class Formula
     path if path =~ %r{#{HOMEBREW_TAP_DIR_REGEX}/Aliases}
   end
 
+  def installed_alias_name
+    File.basename(installed_alias_path) if installed_alias_path
+  end
+
+  def full_installed_alias_name
+    get_full_name(installed_alias_name)
+  end
+
   # The path that was specified to find this formula.
   def specified_path
     alias_path || path
   end
 
+  # The name specified to find this formula.
+  def specified_name
+    alias_name || name
+  end
+
+  # The name (including tap) specified to find this formula.
+  def full_specified_name
+    full_alias_name || full_name
+  end
+
+  # The name specified to install this formula.
+  def installed_specified_name
+    installed_alias_name || name
+  end
+
+  # The name (including tap) specified to install this formula.
+  def full_installed_specified_name
+    full_installed_alias_name || full_name
+  end
+
   # Is the currently active {SoftwareSpec} a {#stable} build?
   # @private
   def stable?
@@ -1067,39 +1120,77 @@ class Formula
   end
 
   # @private
-  def outdated_versions(options = {})
-    @outdated_versions ||= Hash.new do |cache, key|
+  def outdated_kegs(options = {})
+    @outdated_kegs ||= Hash.new do |cache, key|
       raise Migrator::MigrationNeededError, self if migration_needed?
-      cache[key] = _outdated_versions(key)
+      cache[key] = _outdated_kegs(key)
     end
-    @outdated_versions[options]
+    @outdated_kegs[options]
   end
 
-  def _outdated_versions(options = {})
-    all_versions = []
+  def _outdated_kegs(options = {})
+    all_kegs = []
 
     installed_kegs.each do |keg|
+      all_kegs << keg
       version = keg.version
-      all_versions << version
       next if version.head?
 
       tab = Tab.for_keg(keg)
       next if version_scheme > tab.version_scheme
       next if version_scheme == tab.version_scheme && pkg_version > version
-      return []
+      next if follow_installed_alias? && installed_alias_target_changed?
+
+      return [] # this keg is the current version of the formula, so it's not outdated
     end
 
+    # Even if this formula hasn't been installed, there may be installations
+    # of other formulae which used to be targets of the alias currently
+    # targetting this formula. These should be counted as outdated versions.
+    all_kegs.concat old_installed_formulae.flat_map(&:installed_kegs)
+
     head_version = latest_head_version
     if head_version && !head_version_outdated?(head_version, options)
       []
     else
-      all_versions.sort
+      all_kegs.sort_by(&:version)
     end
   end
 
+  def current_installed_alias_target
+    Formulary.factory(installed_alias_path) if installed_alias_path
+  end
+
+  # Has the target of the alias used to install this formula changed?
+  # Returns false if the formula wasn't installed with an alias.
+  def installed_alias_target_changed?
+    ![self, nil].include?(current_installed_alias_target)
+  end
+
+  # Is this formula the target of an alias used to install an old formula?
+  def supersedes_an_installed_formula?
+    old_installed_formulae.any?
+  end
+
+  # Has the alias used to install the formula changed, or are different
+  # formulae already installed with this alias?
+  def alias_changed?
+    installed_alias_target_changed? || supersedes_an_installed_formula?
+  end
+
+  # If the alias has changed value, return the new formula.
+  # Otherwise, return self.
+  def latest_formula
+    installed_alias_target_changed? ? current_installed_alias_target : self
+  end
+
+  def old_installed_formulae
+    alias_path ? self.class.installed_with_alias_path(alias_path) : []
+  end
+
   # @private
   def outdated?(options = {})
-    !outdated_versions(options).empty?
+    !outdated_kegs(options).empty?
   rescue Migrator::MigrationNeededError
     true
   end
@@ -1254,6 +1345,11 @@ class Formula
     end.compact
   end
 
+  def self.installed_with_alias_path(alias_path)
+    return [] if alias_path.nil?
+    installed.select { |f| f.installed_alias_path == alias_path }
+  end
+
   # an array of all alias files of core {Formula}
   # @private
   def self.core_alias_files
diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index 1cd9dce2a..4c20c2225 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -77,8 +77,11 @@ class Formulary
     end
 
     # Gets the formula instance.
-    def get_formula(spec)
-      klass.new(name, path, spec, alias_path: alias_path)
+    #
+    # `alias_path` can be overridden here in case an alias was used to refer to
+    # a formula that was loaded in another way.
+    def get_formula(spec, alias_path: nil)
+      klass.new(name, path, spec, alias_path: alias_path || self.alias_path)
     end
 
     def klass
@@ -103,7 +106,7 @@ class Formulary
       super name, Formulary.path(full_name)
     end
 
-    def get_formula(spec)
+    def get_formula(spec, alias_path: nil)
       formula = super
       formula.local_bottle_path = @bottle_filename
       formula_version = formula.pkg_version
@@ -120,7 +123,7 @@ class Formulary
       path = alias_path.resolved_path
       name = path.basename(".rb").to_s
       super name, path
-      @alias_path = alias_path
+      @alias_path = alias_path.to_s
     end
   end
 
@@ -175,7 +178,7 @@ class Formulary
       super name, path
     end
 
-    def get_formula(spec)
+    def get_formula(spec, alias_path: nil)
       super
     rescue FormulaUnavailableError => e
       raise TapFormulaUnavailableError.new(tap, name), "", e.backtrace
@@ -187,7 +190,7 @@ class Formulary
       super name, Formulary.core_path(name)
     end
 
-    def get_formula(_spec)
+    def get_formula(_spec, alias_path: nil)
       raise FormulaUnavailableError, name
     end
   end
@@ -215,38 +218,42 @@ class Formulary
   # * a formula pathname
   # * a formula URL
   # * a local bottle reference
-  def self.factory(ref, spec = :stable)
-    loader_for(ref).get_formula(spec)
+  def self.factory(ref, spec = :stable, alias_path: nil)
+    loader_for(ref).get_formula(spec, alias_path: alias_path)
   end
 
   # Return a Formula instance for the given rack.
   # It will auto resolve formula's spec when requested spec is nil
-  def self.from_rack(rack, spec = nil)
+  #
+  # The :alias_path option will be used if the formula is found not to be
+  # installed, and discarded if it is installed because the alias_path used
+  # to install the formula will be set instead.
+  def self.from_rack(rack, spec = nil, alias_path: nil)
     kegs = rack.directory? ? rack.subdirs.map { |d| Keg.new(d) } : []
     keg = kegs.detect(&:linked?) || kegs.detect(&:optlinked?) || kegs.max_by(&:version)
 
     if keg
-      from_keg(keg, spec)
+      from_keg(keg, spec, :alias_path => alias_path)
     else
-      factory(rack.basename.to_s, spec || :stable)
+      factory(rack.basename.to_s, spec || :stable, :alias_path => alias_path)
     end
   end
 
   # Return a Formula instance for the given keg.
   # It will auto resolve formula's spec when requested spec is nil
-  def self.from_keg(keg, spec = nil)
+  def self.from_keg(keg, spec = nil, alias_path: nil)
     tab = Tab.for_keg(keg)
     tap = tab.tap
     spec ||= tab.spec
 
     f = if tap.nil?
-      factory(keg.rack.basename.to_s, spec)
+      factory(keg.rack.basename.to_s, spec, :alias_path => alias_path)
     else
       begin
-        factory("#{tap}/#{keg.rack.basename}", spec)
+        factory("#{tap}/#{keg.rack.basename}", spec, :alias_path => alias_path)
       rescue FormulaUnavailableError
         # formula may be migrated to different tap. Try to search in core and all taps.
-        factory(keg.rack.basename.to_s, spec)
+        factory(keg.rack.basename.to_s, spec, :alias_path => alias_path)
       end
     end
     f.build = tab
@@ -346,7 +353,7 @@ class Formulary
   end
 
   def self.core_path(name)
-    CoreTap.instance.formula_dir/"#{name.downcase}.rb"
+    CoreTap.instance.formula_dir/"#{name.to_s.downcase}.rb"
   end
 
   def self.tap_paths(name, taps = Dir["#{HOMEBREW_LIBRARY}/Taps/*/*/"])
diff --git a/Library/Homebrew/test/test_formulary.rb b/Library/Homebrew/test/test_formulary.rb
index 8b3417dad..c545ff84d 100644
--- a/Library/Homebrew/test/test_formulary.rb
+++ b/Library/Homebrew/test/test_formulary.rb
@@ -89,7 +89,7 @@ class FormularyFactoryTest < Homebrew::TestCase
     FileUtils.ln_s @path, alias_path
     result = Formulary.factory("foo")
     assert_kind_of Formula, result
-    assert_equal alias_path, result.alias_path
+    assert_equal alias_path.to_s, result.alias_path
   ensure
     alias_dir.rmtree
   end