Move inflection utils to Utils module

Library/Homebrew/utils.rb

@@ -12,7 +12,6 @@ require "utils/git"
 require "utils/git_repository"
 require "utils/github"
 require "utils/gzip"
-require "utils/inflection"
 require "utils/inreplace"
 require "utils/link"
 require "utils/popen"
@@ -86,3 +85,50 @@ module Homebrew
   end
   # rubocop:enable Style/GlobalVars
 end
+
+module Utils
+  extend T::Sig
+
+  # Removes the rightmost segment from the constant expression in the string.
+  #
+  #   deconstantize('Net::HTTP')   # => "Net"
+  #   deconstantize('::Net::HTTP') # => "::Net"
+  #   deconstantize('String')      # => ""
+  #   deconstantize('::String')    # => ""
+  #   deconstantize('')            # => ""
+  #
+  # See also #demodulize.
+  # @see https://github.com/rails/rails/blob/b0dd7c7/activesupport/lib/active_support/inflector/methods.rb#L247-L258
+  #   `ActiveSupport::Inflector.deconstantize`
+  sig { params(path: String).returns(String) }
+  def self.deconstantize(path)
+    T.must(path[0, path.rindex("::") || 0]) # implementation based on the one in facets' Module#spacename
+  end
+
+  # Removes the module part from the expression in the string.
+  #
+  #   demodulize('ActiveSupport::Inflector::Inflections') # => "Inflections"
+  #   demodulize('Inflections')                           # => "Inflections"
+  #   demodulize('::Inflections')                         # => "Inflections"
+  #   demodulize('')                                      # => ""
+  #
+  # See also #deconstantize.
+  # @see https://github.com/rails/rails/blob/b0dd7c7/activesupport/lib/active_support/inflector/methods.rb#L230-L245
+  #   `ActiveSupport::Inflector.demodulize`
+  sig { params(path: String).returns(String) }
+  def self.demodulize(path)
+    if (i = path.rindex("::"))
+      T.must(path[(i + 2)..])
+    else
+      path
+    end
+  end
+
+  # A lightweight alternative to `ActiveSupport::Inflector.pluralize`:
+  # Combines `stem` with the `singular` or `plural` suffix based on `count`.
+  sig { params(stem: String, count: Integer, plural: String, singular: String).returns(String) }
+  def self.pluralize(stem, count, plural: "s", singular: "")
+    suffix = (count == 1) ? singular : plural
+    "#{stem}#{suffix}"
+  end
+end