API: supply additional data for requirements

Library/Homebrew/formula.rb

@@ -1690,10 +1690,13 @@ class Formula
     end
 
     hsh["requirements"] = requirements.map do |req|
+      req.name.prepend("maximum_") if req.try(:comparator) == "<="
       {
         "name"     => req.name,
         "cask"     => req.cask,
         "download" => req.download,
+        "version"  => req.try(:version),
+        "contexts" => req.tags,
       }
     end
 

Library/Homebrew/requirements/java_requirement.rb

@@ -3,10 +3,10 @@
 require "language/java"
 
 class JavaRequirement < Requirement
-  attr_reader :java_home
-
   fatal true
 
+  attr_reader :java_home, :version
+
   # A strict Java 8 requirement (1.8) should prompt the user to install
   # an OpenJDK 1.8 distribution. Versions newer than Java 8 are not
   # completely backwards compatible, and contain breaking changes such as

Library/Homebrew/requirements/macos_requirement.rb

@@ -5,6 +5,8 @@ require "requirement"
 class MacOSRequirement < Requirement
   fatal true
 
+  attr_reader :comparator, :version
+
   def initialize(tags = [], comparator: ">=")
     if comparator == "==" && tags.first.respond_to?(:map)
       @version = tags.shift.map { |s| MacOS::Version.from_symbol(s) }
@@ -54,6 +56,10 @@ class MacOSRequirement < Requirement
     end
   end
 
+  def inspect
+    "#<#{self.class.name}: #{tags.inspect} version#{@comparator}#{@version}>"
+  end
+
   def display_s
     return "macOS is required" unless version_specified?
 

Library/Homebrew/requirements/xcode_requirement.rb

@@ -5,6 +5,8 @@ require "requirement"
 class XcodeRequirement < Requirement
   fatal true
 
+  attr_reader :version
+
   satisfy(build_env: false) { xcode_installed_version }
 
   def initialize(tags = [])