Improve test coverage of WIF decoder/encoder

Use subtests to split cases, and add new ones, notably for decoding
invalid WIFs.

wif_test.go

@@ -1,10 +1,12 @@
-// Copyright (c) 2013, 2014 The btcsuite developers
+// Copyright (c) 2013 - 2020 The btcsuite developers
 // Use of this source code is governed by an ISC
 // license that can be found in the LICENSE file.
 
 package btcutil_test
 
 import (
+	"bytes"
+	"encoding/hex"
 	"testing"
 
 	"github.com/btcsuite/btcd/btcec"
@@ -13,59 +15,142 @@ import (
 )
 
 func TestEncodeDecodeWIF(t *testing.T) {
-	priv1, _ := btcec.PrivKeyFromBytes(btcec.S256(), []byte{
+	validEncodeCases := []struct {
+		privateKey []byte           // input
+		net        *chaincfg.Params // input
+		compress   bool             // input
+		wif        string           // output
+		publicKey  []byte           // output
+		name       string           // name of subtest
+	}{
+		{
+			privateKey: []byte{
 				0x0c, 0x28, 0xfc, 0xa3, 0x86, 0xc7, 0xa2, 0x27,
 				0x60, 0x0b, 0x2f, 0xe5, 0x0b, 0x7c, 0xae, 0x11,
 				0xec, 0x86, 0xd3, 0xbf, 0x1f, 0xbe, 0x47, 0x1b,
-		0xe8, 0x98, 0x27, 0xe1, 0x9d, 0x72, 0xaa, 0x1d})
+				0xe8, 0x98, 0x27, 0xe1, 0x9d, 0x72, 0xaa, 0x1d},
-
+			net:      &chaincfg.MainNetParams,
-	priv2, _ := btcec.PrivKeyFromBytes(btcec.S256(), []byte{
+			compress: false,
+			wif:      "5HueCGU8rMjxEXxiPuD5BDku4MkFqeZyd4dZ1jvhTVqvbTLvyTJ",
+			publicKey: []byte{
+				0x04, 0xd0, 0xde, 0x0a, 0xae, 0xae, 0xfa, 0xd0,
+				0x2b, 0x8b, 0xdc, 0x8a, 0x01, 0xa1, 0xb8, 0xb1,
+				0x1c, 0x69, 0x6b, 0xd3, 0xd6, 0x6a, 0x2c, 0x5f,
+				0x10, 0x78, 0x0d, 0x95, 0xb7, 0xdf, 0x42, 0x64,
+				0x5c, 0xd8, 0x52, 0x28, 0xa6, 0xfb, 0x29, 0x94,
+				0x0e, 0x85, 0x8e, 0x7e, 0x55, 0x84, 0x2a, 0xe2,
+				0xbd, 0x11, 0x5d, 0x1e, 0xd7, 0xcc, 0x0e, 0x82,
+				0xd9, 0x34, 0xe9, 0x29, 0xc9, 0x76, 0x48, 0xcb,
+				0x0a},
+			name: "encodeValidUncompressedMainNetWif",
+		},
+		{
+			privateKey: []byte{
 				0xdd, 0xa3, 0x5a, 0x14, 0x88, 0xfb, 0x97, 0xb6,
 				0xeb, 0x3f, 0xe6, 0xe9, 0xef, 0x2a, 0x25, 0x81,
 				0x4e, 0x39, 0x6f, 0xb5, 0xdc, 0x29, 0x5f, 0xe9,
-		0x94, 0xb9, 0x67, 0x89, 0xb2, 0x1a, 0x03, 0x98})
+				0x94, 0xb9, 0x67, 0x89, 0xb2, 0x1a, 0x03, 0x98},
-
+			net:      &chaincfg.TestNet3Params,
-	wif1, err := NewWIF(priv1, &chaincfg.MainNetParams, false)
+			compress: true,
-	if err != nil {
+			wif:      "cV1Y7ARUr9Yx7BR55nTdnR7ZXNJphZtCCMBTEZBJe1hXt2kB684q",
-		t.Fatal(err)
+			publicKey: []byte{
-	}
+				0x02, 0xee, 0xc2, 0x54, 0x06, 0x61, 0xb0, 0xc3,
-	wif2, err := NewWIF(priv2, &chaincfg.TestNet3Params, true)
+				0x9d, 0x27, 0x15, 0x70, 0x74, 0x24, 0x13, 0xbd,
-	if err != nil {
+				0x02, 0x93, 0x2d, 0xd0, 0x09, 0x34, 0x93, 0xfd,
-		t.Fatal(err)
+				0x0b, 0xec, 0xed, 0x0b, 0x7f, 0x93, 0xad, 0xde,
-	}
+				0xc4},
-
+			name: "encodeValidCompressedTestNet3Wif",
-	tests := []struct {
-		wif     *WIF
-		encoded string
-	}{
-		{
-			wif1,
-			"5HueCGU8rMjxEXxiPuD5BDku4MkFqeZyd4dZ1jvhTVqvbTLvyTJ",
-		},
-		{
-			wif2,
-			"cV1Y7ARUr9Yx7BR55nTdnR7ZXNJphZtCCMBTEZBJe1hXt2kB684q",
 		},
 	}
 
-	for _, test := range tests {
+	for _, validCase := range validEncodeCases {
+		t.Run(validCase.name, func(t *testing.T) {
+			priv, _ := btcec.PrivKeyFromBytes(btcec.S256(), validCase.privateKey)
+			wif, err := NewWIF(priv, validCase.net, validCase.compress)
+			if err != nil {
+				t.Fatalf("NewWIF failed: expected no error, got '%v'", err)
+			}
+
+			if !wif.IsForNet(validCase.net) {
+				t.Fatal("IsForNet failed: got 'false', want 'true'")
+			}
+
+			if gotPubKey := wif.SerializePubKey(); !bytes.Equal(gotPubKey, validCase.publicKey) {
+				t.Fatalf("SerializePubKey failed: got '%s', want '%s'",
+					hex.EncodeToString(gotPubKey), hex.EncodeToString(validCase.publicKey))
+			}
+
 			// Test that encoding the WIF structure matches the expected string.
-		s := test.wif.String()
+			got := wif.String()
-		if s != test.encoded {
+			if got != validCase.wif {
-			t.Errorf("TestEncodeDecodePrivateKey failed: want '%s', got '%s'",
+				t.Fatalf("NewWIF failed: want '%s', got '%s'",
-				test.encoded, s)
+					validCase.wif, got)
-			continue
 			}
 
 			// Test that decoding the expected string results in the original WIF
 			// structure.
-		w, err := DecodeWIF(test.encoded)
+			decodedWif, err := DecodeWIF(got)
 			if err != nil {
-			t.Error(err)
+				t.Fatalf("DecodeWIF failed: expected no error, got '%v'", err)
-			continue
 			}
-		if got := w.String(); got != test.encoded {
+			if decodedWifString := decodedWif.String(); decodedWifString != validCase.wif {
-			t.Errorf("NewWIF failed: want '%v', got '%v'", test.wif, got)
+				t.Fatalf("NewWIF failed: want '%v', got '%v'", validCase.wif, decodedWifString)
 			}
+		})
 	}
+
+	invalidDecodeCases := []struct {
+		name string
+		wif  string
+		err  error
+	}{
+		{
+			name: "decodeInvalidLengthWif",
+			wif:  "deadbeef",
+			err:  ErrMalformedPrivateKey,
+		},
+		{
+			name: "decodeInvalidCompressMagicWif",
+			wif:  "KwDiBf89QgGbjEhKnhXJuH7LrciVrZi3qYjgd9M7rFU73sfZr2ym",
+			err:  ErrMalformedPrivateKey,
+		},
+		{
+			name: "decodeInvalidChecksumWif",
+			wif:  "5HueCGU8rMjxEXxiPuD5BDku4MkFqeZyd4dZ1jvhTVqvbTLvyTj",
+			err:  ErrChecksumMismatch,
+		},
+	}
+
+	for _, invalidCase := range invalidDecodeCases {
+		t.Run(invalidCase.name, func(t *testing.T) {
+			decodedWif, err := DecodeWIF(invalidCase.wif)
+			if decodedWif != nil {
+				t.Fatalf("DecodeWIF: unexpectedly succeeded - got '%v', want '%v'",
+					decodedWif, nil)
+			}
+			if err != invalidCase.err {
+				t.Fatalf("DecodeWIF: expected error '%v', got '%v'",
+					invalidCase.err, err)
+			}
+		})
+	}
+
+	t.Run("encodeInvalidNetworkWif", func(t *testing.T) {
+		privateKey := []byte{
+			0x0c, 0x28, 0xfc, 0xa3, 0x86, 0xc7, 0xa2, 0x27,
+			0x60, 0x0b, 0x2f, 0xe5, 0x0b, 0x7c, 0xae, 0x11,
+			0xec, 0x86, 0xd3, 0xbf, 0x1f, 0xbe, 0x47, 0x1b,
+			0xe8, 0x98, 0x27, 0xe1, 0x9d, 0x72, 0xaa, 0x1d}
+		priv, _ := btcec.PrivKeyFromBytes(btcec.S256(), privateKey)
+
+		wif, err := NewWIF(priv, nil, true)
+
+		if wif != nil {
+			t.Fatalf("NewWIF: unexpectedly succeeded - got '%v', want '%v'",
+				wif, nil)
+		}
+		if err == nil || err.Error() != "no network" {
+			t.Fatalf("NewWIF: expected error 'no network', got '%v'", err)
+		}
+	})
 }