[#216] netmap: Add policy decode fuzz test

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

go.mod

@@ -34,6 +34,7 @@ require (
 	github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20230615193820-9185820289ce // indirect
 	github.com/nspcc-dev/rfc6979 v0.2.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/rogpeppe/go-internal v1.8.1 // indirect
 	github.com/twmb/murmur3 v1.1.8 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	go.uber.org/goleak v1.2.1 // indirect

netmap/policy_decode_test.go

@@ -7,8 +7,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestDecodeString(t *testing.T) {
-	testCases := []string{
+var validPlacementPolicy = []string{
 	`REP 2
 CBF 2
 SELECT 2 FROM *`,
@@ -46,11 +45,12 @@ REP 1
 REP 1`,
 	`EC 1.2 IN X
 SELECT 3 IN City FROM * AS X`,
-	}
+}
 
+func TestDecodeString(t *testing.T) {
 	var p PlacementPolicy
 
-	for _, testCase := range testCases {
+	for _, testCase := range validPlacementPolicy {
 		require.NoError(t, p.DecodeString(testCase), "unable parse %s", testCase)
 		var b strings.Builder
 		require.NoError(t, p.WriteStringTo(&b))

netmap/policy_fuzz.go

@@ -0,0 +1,14 @@
+//go:build gofuzz
+// +build gofuzz
+
+package netmap
+
+func DoFuzzPlacementPolicyDecode(data []byte) int {
+	p := string(data)
+	if p == "" {
+		return 0
+	}
+	var pp PlacementPolicy
+	_ = pp.DecodeString(p)
+	return 1
+}

netmap/policy_fuzz_test.go

@@ -0,0 +1,17 @@
+//go:build gofuzz
+// +build gofuzz
+
+package netmap
+
+import (
+	"testing"
+)
+
+func FuzzDecodeString(f *testing.F) {
+	for _, pp := range validPlacementPolicy {
+		f.Add([]byte(pp))
+	}
+	f.Fuzz(func(t *testing.T, data []byte) {
+		DoFuzzPlacementPolicyDecode(data)
+	})
+}