Add option_name tests.

Library/Homebrew/test/test_build_options.rb

@@ -20,6 +20,7 @@ class BuildOptionsTests < Homebrew::TestCase
     assert @build.with?("bar")
     assert @build.with?("baz")
     assert @build.without?("qux")
+    assert @build.without?("xyz")
   end
 
   def test_used_options

Library/Homebrew/test/test_dependency.rb

@@ -52,3 +52,10 @@ class DependencyTests < Homebrew::TestCase
     refute_eql foo1, foo3
   end
 end
+
+class TapDependencyTests < Homebrew::TestCase
+  def test_option_name
+    dep = TapDependency.new("foo/bar/dog")
+    assert_equal "dog", dep.option_name
+  end
+end

Library/Homebrew/test/test_requirement.rb

@@ -2,6 +2,8 @@ require "testing_env"
 require "requirement"
 
 class RequirementTests < Homebrew::TestCase
+  class TestRequirement < Requirement; end
+
   def test_accepts_single_tag
     dep = Requirement.new(%w[bar])
     assert_equal %w[bar], dep.tags
@@ -12,6 +14,11 @@ class RequirementTests < Homebrew::TestCase
     assert_equal %w[bar baz].sort, dep.tags.sort
   end
 
+  def test_option_name
+    dep = TestRequirement.new
+    assert_equal "test", dep.option_name
+  end
+
   def test_preserves_symbol_tags
     dep = Requirement.new([:build])
     assert_equal [:build], dep.tags