diff --git a/spec/oga/css/evaluator/operators_spec.rb b/spec/oga/css/evaluator/operators_spec.rb
new file mode 100644
index 0000000..459673f
--- /dev/null
+++ b/spec/oga/css/evaluator/operators_spec.rb
@@ -0,0 +1,101 @@
+require 'spec_helper'
+
+describe 'CSS selector evaluation' do
+  context 'operators' do
+    context '= operator' do
+      before do
+        @document = parse('<x a="b" />')
+      end
+
+      example 'return a node set containing nodes with matching attributes' do
+        evaluate_css(@document, 'x[a = "b"]').should == @document.children
+      end
+
+      example 'return an empty node set for non matching attribute values' do
+        evaluate_css(@document, 'x[a = "c"]').should == node_set
+      end
+    end
+
+    context '~= operator' do
+      example 'return a node set containing nodes with matching attributes' do
+        document = parse('<x a="1 2 3" />')
+
+        evaluate_css(document, 'x[a ~= "2"]').should == document.children
+      end
+
+      example 'return a node set containing nodes with single attribute values' do
+        document = parse('<x a="1" />')
+
+        evaluate_css(document, 'x[a ~= "1"]').should == document.children
+      end
+
+      example 'return an empty node set for non matching attributes' do
+        document = parse('<x a="1 2 3" />')
+
+        evaluate_css(document, 'x[a ~= "4"]').should == node_set
+      end
+    end
+
+    context '^= operator' do
+      before do
+        @document = parse('<x a="foo" />')
+      end
+
+      example 'return a node set containing nodes with matching attributes' do
+        evaluate_css(@document, 'x[a ^= "fo"]').should == @document.children
+      end
+
+      example 'return an empty node set for non matching attributes' do
+        evaluate_css(@document, 'x[a ^= "bar"]').should == node_set
+      end
+    end
+
+    context '$= operator' do
+      before do
+        @document = parse('<x a="foo" />')
+      end
+
+      example 'return a node set containing nodes with matching attributes' do
+        evaluate_css(@document, 'x[a $= "oo"]').should == @document.children
+      end
+
+      example 'return an empty node set for non matching attributes' do
+        evaluate_css(@document, 'x[a $= "x"]').should == node_set
+      end
+    end
+
+    context '*= operator' do
+      before do
+        @document = parse('<x a="foo" />')
+      end
+
+      example 'return a node set containing nodes with matching attributes' do
+        evaluate_css(@document, 'x[a *= "o"]').should == @document.children
+      end
+
+      example 'return an empty node set for non matching attributes' do
+        evaluate_css(@document, 'x[a *= "x"]').should == node_set
+      end
+    end
+
+    context '|= operator' do
+      example 'return a node set containing nodes with matching attributes' do
+        document = parse('<x a="foo-bar" />')
+
+        evaluate_css(document, 'x[a |= "foo"]').should == document.children
+      end
+
+      example 'return a node set containing nodes with single attribute values' do
+        document = parse('<x a="foo" />')
+
+        evaluate_css(document, 'x[a |= "foo"]').should == document.children
+      end
+
+      example 'return an empty node set for non matching attributes' do
+        document = parse('<x a="bar" />')
+
+        evaluate_css(document, 'x[a |= "foo"]').should == node_set
+      end
+    end
+  end
+end
diff --git a/spec/oga/css/evaluator/predicates_spec.rb b/spec/oga/css/evaluator/predicates_spec.rb
new file mode 100644
index 0000000..b6bf477
--- /dev/null
+++ b/spec/oga/css/evaluator/predicates_spec.rb
@@ -0,0 +1,19 @@
+require 'spec_helper'
+
+context 'CSS selector evaluation' do
+  context 'predicates' do
+    before do
+      @document = parse('<root><a class="foo" /></root>')
+
+      @a1 = @document.children[0].children[0]
+    end
+
+    example 'return a node set containing nodes with an attribute' do
+      evaluate_css(@document, 'root a[class]').should == node_set(@a1)
+    end
+
+    example 'return a node set containing nodes with a matching attribute value' do
+      evaluate_css(@document, 'root a[class="foo"]').should == node_set(@a1)
+    end
+  end
+end