Simplify build options API

Simplify access to the different forms of a formula's build options by
making options into real objects rather than strings, and expose both
the 'name' and 'flag' form.

Library/Homebrew/cmd/options.rb

@@ -21,7 +21,7 @@ module Homebrew extend self
     ff.each do |f|
       next if f.build.empty?
       if ARGV.include? '--compact'
-        puts f.build.collect {|k,v| "--"+k} * " "
+        puts f.build.as_flags * " "
       else
         puts f.name if ff.length > 1
         dump_options_for_formula f
@@ -31,9 +31,9 @@ module Homebrew extend self
   end
 
   def dump_options_for_formula f
-    f.build.each do |k,v|
-      puts "--"+k
-      puts "\t"+v
+    f.build.each do |opt|
+      puts opt.flag
+      puts "\t"+opt.description
     end
   end
 end

Library/Homebrew/formula_support.rb

@@ -162,6 +162,26 @@ class KegOnlyReason
 end
 
 
+# Represents a build-time option for a formula
+class Option
+  attr_reader :name, :description, :flag
+
+  def initialize name, description=nil
+    @name = name.to_s
+    @description = description.to_s
+    @flag = '--'+name.to_s
+  end
+
+  def eql?(other)
+    @name == other.name
+  end
+
+  def hash
+    @name.hash
+  end
+end
+
+
 # This class holds the build-time options defined for a Formula,
 # and provides named access to those options during install.
 class BuildOptions
@@ -187,19 +207,23 @@ class BuildOptions
       end
     end
 
-    @options << [name, description]
+    @options << Option.new(name, description)
   end
 
   def has_option? name
-    @options.any? { |opt, _| opt == name }
+    any? { |opt| opt.name == name }
   end
 
   def empty?
     @options.empty?
   end
 
-  def each
-    @options.each { |opt, desc| yield opt, desc }
+  def each(&blk)
+    @options.each(&blk)
+  end
+
+  def as_flags
+    map { |opt| opt.flag }
   end
 
   def include? name

Library/Homebrew/tab.rb

@@ -13,7 +13,7 @@ class Tab < OpenStruct
     arg_options = args.options_only
     # Pick off the option flags from the formula's `options` array by
     # discarding the descriptions.
-    formula_options = f.build.map { |opt, _| "--#{opt}" }
+    formula_options = f.build.as_flags
 
     Tab.new :used_options => formula_options & arg_options,
             :unused_options => formula_options - arg_options,
@@ -67,7 +67,7 @@ class Tab < OpenStruct
 
   def self.dummy_tab f
     Tab.new :used_options => [],
-            :unused_options => f.build.map { |opt, _| "--#{opt}" },
+            :unused_options => f.build.as_flags,
             :built_bottle => false,
             :tapped_from => ""
   end