Fix described_class support for new RSpec

lib/bogus/rspec/syntax.rb

@@ -8,6 +8,9 @@ class RSpecSyntax
     def_delegators :context, :before, :after, :described_class
 
     def described_class=(value)
+      # for new RSpec (> 3.0)
+      context.metadata[:described_class] = value
+      # for old RSpec (< 3.0)
       context.example.metadata[:example_group][:described_class] = value
     end
 

spec/bogus/rspec/syntax_spec.rb

@@ -0,0 +1,16 @@
+require 'spec_helper'
+
+describe Bogus::RSpecSyntax do
+  context = self
+  let(:syntax) { Bogus::RSpecSyntax.new(context) }
+
+  it "gets the described class" do
+    expect(syntax.described_class).to eq(Bogus::RSpecSyntax)
+  end
+
+  it "can set the described class" do
+    syntax.described_class = Object
+
+    expect(described_class).to eq(Object)
+  end
+end