1 files changed, 39 insertions, 0 deletions
diff --git a/internal/fuzz/textfuzz/fuzz.go b/internal/fuzz/textfuzz/fuzz.go
new file mode 100644
index 00000000..242e4b63
--- /dev/null
+++ b/internal/fuzz/textfuzz/fuzz.go
@@ -0,0 +1,39 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package textfuzz includes fuzzers for prototext.Marshal and prototext.Unmarshal.
+package textfuzz
+
+import (
+	"google.golang.org/protobuf/encoding/prototext"
+	"google.golang.org/protobuf/proto"
+
+	fuzzpb "google.golang.org/protobuf/internal/testprotos/fuzz"
+)
+
+// Fuzz is a fuzzer for proto.Marshal and proto.Unmarshal.
+func Fuzz(data []byte) (score int) {
+	m1 := &fuzzpb.Fuzz{}
+	if err := (prototext.UnmarshalOptions{
+		AllowPartial: true,
+	}).Unmarshal(data, m1); err != nil {
+		return 0
+	}
+	data1, err := prototext.MarshalOptions{
+		AllowPartial: true,
+	}.Marshal(m1)
+	if err != nil {
+		panic(err)
+	}
+	m2 := &fuzzpb.Fuzz{}
+	if err := (prototext.UnmarshalOptions{
+		AllowPartial: true,
+	}).Unmarshal(data1, m2); err != nil {
+		return 0
+	}
+	if !proto.Equal(m1, m2) {
+		panic("not equal")
+	}
+	return 1
+}