diff --git a/spec/oga/css/evaluator/pseudo_classes/only_child_spec.rb b/spec/oga/css/evaluator/pseudo_classes/only_child_spec.rb
new file mode 100644
index 0000000..d83f540
--- /dev/null
+++ b/spec/oga/css/evaluator/pseudo_classes/only_child_spec.rb
@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+describe 'CSS selector evaluation' do
+  context ':only-child pseudo class' do
+    before do
+      @document = parse('<root><a><c /></a><b><c /></b></root>')
+
+      @root = @document.children[0]
+      @c1   = @root.children[0].children[0]
+      @c2   = @root.children[1].children[0]
+    end
+
+    example 'return a node set containing <c> nodes' do
+      evaluate_css(@document, 'root :only-child').should == node_set(@c1, @c2)
+    end
+  end
+end
diff --git a/spec/oga/css/evaluator/pseudo_classes/only_of_type_spec.rb b/spec/oga/css/evaluator/pseudo_classes/only_of_type_spec.rb
new file mode 100644
index 0000000..8a21230
--- /dev/null
+++ b/spec/oga/css/evaluator/pseudo_classes/only_of_type_spec.rb
@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+describe 'CSS selector evaluation' do
+  context ':only-of-type pseudo class' do
+    before do
+      @document = parse('<root><a><c /></a><b><c /></b></root>')
+
+      @root = @document.children[0]
+      @c1   = @root.children[0].children[0]
+      @c2   = @root.children[1].children[0]
+    end
+
+    example 'return a node set containing <c> nodes' do
+      evaluate_css(@document, 'root a :only-of-type').should == node_set(@c1)
+    end
+  end
+end
diff --git a/spec/oga/css/evaluator/pseudo_classes/root_spec.rb b/spec/oga/css/evaluator/pseudo_classes/root_spec.rb
new file mode 100644
index 0000000..f045f6e
--- /dev/null
+++ b/spec/oga/css/evaluator/pseudo_classes/root_spec.rb
@@ -0,0 +1,13 @@
+require 'spec_helper'
+
+describe 'CSS selector evaluation' do
+  context ':root pseudo class' do
+    before do
+      @document = parse('<root><a /></root>')
+    end
+
+    example 'return a node set containing the root node' do
+      evaluate_css(@document, ':root').should == @document.children
+    end
+  end
+end