test: types/bech32: fuzz ConvertAndEncode (#16523)

types/bech32/fuzz_test.go

@@ -0,0 +1,50 @@
+package bech32
+
+import (
+	"crypto/sha256"
+	"encoding/json"
+	"testing"
+)
+
+type hrpAndData struct {
+	HRP  string `json:"h"`
+	Data []byte `json:"d"`
+}
+
+func FuzzConvertAndEncode(f *testing.F) {
+	// 1. Add seeds
+	seeds := []*hrpAndData{
+		{
+			"shasum",
+			func() []byte {
+				sum := sha256.Sum256([]byte("hello world\n"))
+				return sum[:]
+			}(),
+		},
+		{
+			"shasum",
+			[]byte("49yfqne0parehrupja55kvqcfvxja5wpe54pas8mshffngvj53rs93fk75"),
+		},
+		{
+			"bech32",
+			[]byte("er8m900ayvv9rg5r6ush4nzvqhj4p9tqnxqkxaaxrs4ueuvhurcs4x3j4j"),
+		},
+	}
+
+	for _, seed := range seeds {
+		seedJSONBlob, err := json.Marshal(seed)
+		if err != nil {
+			continue
+		}
+		f.Add(seedJSONBlob)
+	}
+
+	// 2. Now run the fuzzer.
+	f.Fuzz(func(t *testing.T, inputJSON []byte) {
+		had := new(hrpAndData)
+		if err := json.Unmarshal(inputJSON, had); err != nil {
+			return
+		}
+		_, _ = ConvertAndEncode(had.HRP, had.Data)
+	})
+}