diff --git a/runtime/Go/antlr/interval_set_test.go b/runtime/Go/antlr/interval_set_test.go
new file mode 100644
index 000000000..832559df3
--- /dev/null
+++ b/runtime/Go/antlr/interval_set_test.go
@@ -0,0 +1,51 @@
+package antlr
+
+import (
+	"testing"
+)
+
+func assertInterval(t *testing.T, i *Interval, l int){
+	if i.length() != l{
+		t.Errorf("For interval [%s] [%d] length is expected, [%d] is actual", i.String(), l, i.length())
+	}
+}
+
+func assertString(t *testing.T, result string, expected string){
+	if result != expected{
+		t.Errorf("expected: %s, result:%s", result, expected)
+	}
+}
+
+func TestDefaultIntervalLength(t *testing.T){
+	assertInterval(t, NewInterval(0,0), 1)
+	assertInterval(t, NewInterval(100, 100), 1)
+
+}
+
+func TestIntervalSetAbsorb(t *testing.T){
+	s := NewIntervalSet()
+	s.addRange(10,20)
+	s.addRange(11,19)
+	assertString(t, "10..20", s.toIndexString())
+}
+
+func TestIntervalSetOverlap(t *testing.T){
+	s := NewIntervalSet()
+	s.addRange(10, 20)
+	s.addRange(15, 25)
+	assertString(t, "10..25", s.toIndexString())
+}
+
+func TestIntervalSetIndependent(t *testing.T)  {
+	s := NewIntervalSet()
+	s.addRange(10, 20)
+	s.addRange(30, 40)
+	assertString(t, "{10..20, 30..40}", s.toIndexString())
+}
+
+func TestIntervalSetAdjoint(t *testing.T)  {
+	s := NewIntervalSet()
+	s.addRange(10,20)
+	s.addRange(20, 30)
+	assertString(t, "10..30", s.toIndexString())
+}
\ No newline at end of file