Add RDoc::Options.boolean

Author: nobu

lib/rdoc/options.rb

@@ -1394,4 +1394,15 @@ def self.load_options
     options
   end
 
+  def self.boolean(flag, message = nil)
+    if flag == true or flag == false
+      flag
+    elsif "yes".casecmp(flag) == 0 or "true".casecmp(flag) == 0
+      true
+    elsif "no".casecmp(flag) == 0 or "false".casecmp(flag) == 0
+      false
+    else
+      raise ArgumentError, [message, flag.inspect].compact.join(": ")
+    end
+  end
 end

test/rdoc/test_rdoc_options.rb

@@ -964,6 +964,20 @@ def test_exclude_option_without_default
     assert_not_match exclude, "foo~"
   end
 
+  def test_boolean
+    assert_equal true, RDoc::Options.boolean(true)
+    assert_equal true, RDoc::Options.boolean("true")
+    assert_equal true, RDoc::Options.boolean("yes")
+
+    assert_equal false, RDoc::Options.boolean(false)
+    assert_equal false, RDoc::Options.boolean("false")
+    assert_equal false, RDoc::Options.boolean("no")
+
+    assert_raise(ArgumentError) do
+      RDoc::Options.boolean("unknown")
+    end
+  end
+
   class DummyCoder < Hash
     alias add :[]=
     def tag=(tag)