2 files changed, 35 insertions, 0 deletions
diff --git a/src/encoding/xml/marshal.go b/src/encoding/xml/marshal.go
index 5a49cc3528..3c3b6aca58 100644
--- a/src/encoding/xml/marshal.go
+++ b/src/encoding/xml/marshal.go
@@ -199,6 +199,7 @@ var (
 // elements (including the StartElement itself) will use the declared
 // prefix when encoding names with matching namespace URIs.
 func (enc *Encoder) EncodeToken(t Token) error {
+
 	p := &enc.p
 	switch t := t.(type) {
 	case StartElement:
@@ -245,6 +246,9 @@ func (enc *Encoder) EncodeToken(t Token) error {
 		p.WriteString("<!")
 		p.Write(t)
 		p.WriteString(">")
+	default:
+		return fmt.Errorf("xml: EncodeToken of invalid token type")
+
 	}
 	return p.cachedWriteError()
 }
diff --git a/src/encoding/xml/marshal_test.go b/src/encoding/xml/marshal_test.go
index 78fe841d76..5dc78e748b 100644
--- a/src/encoding/xml/marshal_test.go
+++ b/src/encoding/xml/marshal_test.go
@@ -1906,3 +1906,34 @@ func TestIsValidDirective(t *testing.T) {
 		}
 	}
 }
+
+// Issue 11719. EncodeToken used to silently eat tokens with an invalid type.
+func TestSimpleUseOfEncodeToken(t *testing.T) {
+	var buf bytes.Buffer
+	enc := NewEncoder(&buf)
+	if err := enc.EncodeToken(&StartElement{Name: Name{"", "object1"}}); err == nil {
+		t.Errorf("enc.EncodeToken: pointer type should be rejected")
+	}
+	if err := enc.EncodeToken(&EndElement{Name: Name{"", "object1"}}); err == nil {
+		t.Errorf("enc.EncodeToken: pointer type should be rejected")
+	}
+	if err := enc.EncodeToken(StartElement{Name: Name{"", "object2"}}); err != nil {
+		t.Errorf("enc.EncodeToken: StartElement %s", err)
+	}
+	if err := enc.EncodeToken(EndElement{Name: Name{"", "object2"}}); err != nil {
+		t.Errorf("enc.EncodeToken: EndElement %s", err)
+	}
+	if err := enc.EncodeToken(Universe{}); err == nil {
+		t.Errorf("enc.EncodeToken: invalid type not caught")
+	}
+	if err := enc.Flush(); err != nil {
+		t.Errorf("enc.Flush: %s", err)
+	}
+	if buf.Len() == 0 {
+		t.Errorf("enc.EncodeToken: empty buffer")
+	}
+	want := "<object2></object2>"
+	if buf.String() != want {
+		t.Errorf("enc.EncodeToken: expected %q; got %q", want, buf.String())
+	}
+}