Implement ActiveSupport's Object#blank? directly

.gitignore

@@ -70,16 +70,13 @@
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/hash/except.rb
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/hash/keys.rb
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/hash/slice.rb
-!**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/object/blank.rb
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/object/deep_dup.rb
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/object/duplicable.rb
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/string/exclude.rb
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/string/filters.rb
 !**/vendor/bundle/ruby/*/gems/activesupport-*/lib/active_support/core_ext/string/indent.rb
 
 # Ignore partially included gems where we don't need all files
-**/vendor/bundle/ruby/*/gems/concurrent-ruby-*/lib/*/*.jar
-**/vendor/bundle/ruby/*/gems/i18n-*/lib/i18n/tests*
 **/vendor/gems/mechanize-*/.*
 **/vendor/gems/mechanize-*/*.md
 **/vendor/gems/mechanize-*/*.rdoc
@@ -102,12 +99,14 @@
 **/vendor/bundle/ruby/*/gems/coderay-*/
 **/vendor/bundle/ruby/*/gems/colorize-*/
 **/vendor/bundle/ruby/*/gems/commander-*/
+**/vendor/bundle/ruby/*/gems/concurrent-ruby-*/
 **/vendor/bundle/ruby/*/gems/diff-lcs-*/
 **/vendor/bundle/ruby/*/gems/docile-*/
 **/vendor/bundle/ruby/*/gems/ecma-re-validator-*/
 **/vendor/bundle/ruby/*/gems/hana-*/
 **/vendor/bundle/ruby/*/gems/highline-*/
 **/vendor/bundle/ruby/*/gems/hpricot-*/
+**/vendor/bundle/ruby/*/gems/i18n-*/
 **/vendor/bundle/ruby/*/gems/jaro_winkler-*/
 **/vendor/bundle/ruby/*/gems/json-*/
 **/vendor/bundle/ruby/*/gems/json_schemer-*/

Library/.rubocop.yml

@@ -232,6 +232,9 @@ Rails/Presence:
   Enabled: true
 Rails/Present:
   Enabled: true
+  Exclude:
+    # `present?` is defined as `!blank?` wihin this file
+    - "Homebrew/extend/blank.rb"
 Rails/RelativeDateConstant:
   Enabled: true
 Rails/SafeNavigation:

Library/Homebrew/vendor/bundle/ruby/2.6.0/gems/activesupport-6.1.7.6/lib/active_support/core_ext/object/blank.rb → Library/Homebrew/extend/blank.rb

@@ -1,7 +1,6 @@
+# typed: strict
 # frozen_string_literal: true
 
-require "concurrent/map"
-
 class Object
   # An object is blank if it's false, empty, or a whitespace string.
   # For example, +nil+, '', '   ', [], {}, and +false+ are all blank.
@@ -13,15 +12,13 @@ class Object
   # to
   #
   #   address.blank?
-  #
-  # @return [true, false]
+  sig { returns(T::Boolean) }
   def blank?
-    respond_to?(:empty?) ? !!empty? : !self
+    respond_to?(:empty?) ? !!T.unsafe(self).empty? : false
   end
 
   # An object is present if it's not blank.
-  #
-  # @return [true, false]
+  sig { returns(T::Boolean) }
   def present?
     !blank?
   end
@@ -40,8 +37,7 @@ def present?
   # becomes
   #
   #   region = params[:state].presence || params[:country].presence || 'US'
-  #
-  # @return [Object]
+  sig { returns(T.nilable(T.self_type)) }
   def presence
     self if present?
   end
@@ -51,33 +47,45 @@ class NilClass
   # +nil+ is blank:
   #
   #   nil.blank? # => true
-  #
-  # @return [true]
+  sig { returns(TrueClass) }
   def blank?
     true
   end
+
+  sig { returns(FalseClass) }
+  def present? # :nodoc:
+    false
+  end
 end
 
 class FalseClass
   # +false+ is blank:
   #
   #   false.blank? # => true
-  #
-  # @return [true]
+  sig { returns(TrueClass) }
   def blank?
     true
   end
+
+  sig { returns(FalseClass) }
+  def present? # :nodoc:
+    false
+  end
 end
 
 class TrueClass
   # +true+ is not blank:
   #
   #   true.blank? # => false
-  #
-  # @return [false]
+  sig { returns(FalseClass) }
   def blank?
     false
   end
+
+  sig { returns(TrueClass) }
+  def present? # :nodoc:
+    true
+  end
 end
 
 class Array
@@ -87,7 +95,12 @@ class Array
   #   [1,2,3].blank? # => false
   #
   # @return [true, false]
-  alias_method :blank?, :empty?
+  alias blank? empty?
+
+  sig { returns(T::Boolean) }
+  def present? # :nodoc:
+    !empty?
+  end
 end
 
 class Hash
@@ -97,14 +110,35 @@ class Hash
   #   { key: 'value' }.blank?  # => false
   #
   # @return [true, false]
-  alias_method :blank?, :empty?
+  alias blank? empty?
+
+  sig { returns(T::Boolean) }
+  def present? # :nodoc:
+    !empty?
+  end
+end
+
+class Symbol
+  # A Symbol is blank if it's empty:
+  #
+  #   :''.blank?     # => true
+  #   :symbol.blank? # => false
+  alias blank? empty?
+
+  sig { returns(T::Boolean) }
+  def present? # :nodoc:
+    !empty?
+  end
 end
 
 class String
-  BLANK_RE = /\A[[:space:]]*\z/
-  ENCODED_BLANKS = Concurrent::Map.new do |h, enc|
+  BLANK_RE = /\A[[:space:]]*\z/.freeze
+  # This is a cache that is intentionally mutable
+  # rubocop:disable Style/MutableConstant
+  ENCODED_BLANKS_ = T.let(Hash.new do |h, enc|
     h[enc] = Regexp.new(BLANK_RE.source.encode(enc), BLANK_RE.options | Regexp::FIXEDENCODING)
-  end
+  end, T::Hash[Encoding, Regexp])
+  # rubocop:enable Style/MutableConstant
 
   # A string is blank if it's empty or contains whitespaces only:
   #
@@ -116,8 +150,7 @@ class String
   # Unicode whitespace is supported:
   #
   #   "\u00a0".blank? # => true
-  #
-  # @return [true, false]
+  sig { returns(T::Boolean) }
   def blank?
     # The regexp that matches blank strings is expensive. For the case of empty
     # strings we can speed up this method (~3.5x) with an empty? call. The
@@ -126,30 +159,43 @@ def blank?
       begin
         BLANK_RE.match?(self)
       rescue Encoding::CompatibilityError
-        ENCODED_BLANKS[self.encoding].match?(self)
+        T.must(ENCODED_BLANKS_[encoding]).match?(self)
       end
   end
+
+  sig { returns(T::Boolean) }
+  def present? # :nodoc:
+    !blank?
+  end
 end
 
-class Numeric #:nodoc:
+class Numeric # :nodoc:
   # No number is blank:
   #
   #   1.blank? # => false
   #   0.blank? # => false
-  #
-  # @return [false]
+  sig { returns(FalseClass) }
   def blank?
     false
   end
+
+  sig { returns(TrueClass) }
+  def present?
+    true
+  end
 end
 
-class Time #:nodoc:
+class Time # :nodoc:
   # No Time is blank:
   #
   #   Time.now.blank? # => false
-  #
-  # @return [false]
+  sig { returns(FalseClass) }
   def blank?
     false
   end
+
+  sig { returns(TrueClass) }
+  def present?
+    true
+  end
 end

Library/Homebrew/global.rb

@@ -18,7 +18,6 @@
 require "active_support/core_ext/hash/deep_merge"
 require "active_support/core_ext/hash/except"
 require "active_support/core_ext/hash/keys"
-require "active_support/core_ext/object/blank"
 require "active_support/core_ext/string/exclude"
 require "active_support/core_ext/string/filters"
 require "active_support/core_ext/string/indent"
@@ -75,6 +74,7 @@
 HOMEBREW_BOTTLES_EXTNAME_REGEX = /\.([a-z0-9_]+)\.bottle\.(?:(\d+)\.)?tar\.gz$/.freeze
 
 require "extend/module"
+require "extend/blank"
 require "env_config"
 require "macos_version"
 require "os"

Library/Homebrew/test/extend/blank_spec.rb

@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+require "extend/blank"
+
+describe Object do
+  let(:empty_true) do
+    Class.new(described_class) do
+      def empty?
+        0
+      end
+    end
+  end
+  let(:empty_false) do
+    Class.new(described_class) do
+      def empty?
+        nil
+      end
+    end
+  end
+  let(:blank) { [empty_true.new, nil, false, "", "   ", "  \n\t  \r ", "　", "\u00a0", [], {}] }
+  let(:present) { [empty_false.new, described_class.new, true, 0, 1, "a", [nil], { nil => 0 }, Time.now] }
+
+  describe ".blank?" do
+    it "checks if an object is blank" do
+      blank.each { |v| expect(v.blank?).to be true }
+      present.each { |v| expect(v.blank?).to be false }
+    end
+
+    it "checks if an object is blank with bundled string encodings" do
+      Encoding.list.reject(&:dummy?).each do |encoding|
+        expect(" ".encode(encoding).blank?).to be true
+        expect("a".encode(encoding).blank?).to be false
+      end
+    end
+  end
+
+  describe ".present?" do
+    it "checks if an object is present" do
+      blank.each { |v| expect(v.present?).to be false }
+      present.each { |v| expect(v.present?).to be true }
+    end
+  end
+
+  describe ".presence" do
+    it "returns the object if present, or nil" do
+      blank.each { |v| expect(v.presence).to be_nil }
+      present.each { |v| expect(v.presence).to be v }
+    end
+  end
+end