internal/guide: initial test suite to ensure guide snippets run ok (#3582)

internal/guide/guide.go

@@ -0,0 +1,18 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// Package guide is a small test suite to ensure snippets in the dev guide work.
+package guide

internal/guide/guide_test.go

@@ -0,0 +1,100 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// This file contains the code snippets from the developer's guide embedded into
+// Go tests. This ensures that any code published in out guides will not break
+// accidentally via some code update. If some API changes nonetheless that needs
+// modifying this file, please port any modification over into the developer's
+// guide wiki pages too!
+
+package guide
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/common"
+)
+
+// Tests that the account management snippets work correctly.
+func TestAccountManagement(t *testing.T) {
+	// Create a temporary folder to work with
+	workdir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatalf("Failed to create temporary work dir: %v", err)
+	}
+	defer os.RemoveAll(workdir)
+
+	// Create an encrypted keystore manager with standard crypto parameters
+	am := accounts.NewManager(filepath.Join(workdir, "keystore"), accounts.StandardScryptN, accounts.StandardScryptP)
+
+	// Create a new account with the specified encryption passphrase
+	newAcc, err := am.NewAccount("Creation password")
+	if err != nil {
+		t.Fatalf("Failed to create new account: %v", err)
+	}
+	// Export the newly created account with a different passphrase. The returned
+	// data from this method invocation is a JSON encoded, encrypted key-file
+	jsonAcc, err := am.Export(newAcc, "Creation password", "Export password")
+	if err != nil {
+		t.Fatalf("Failed to export account: %v", err)
+	}
+	// Update the passphrase on the account created above inside the local keystore
+	if err := am.Update(newAcc, "Creation password", "Update password"); err != nil {
+		t.Fatalf("Failed to update account: %v", err)
+	}
+	// Delete the account updated above from the local keystore
+	if err := am.Delete(newAcc, "Update password"); err != nil {
+		t.Fatalf("Failed to delete account: %v", err)
+	}
+	// Import back the account we've exported (and then deleted) above with yet
+	// again a fresh passphrase
+	if _, err := am.Import(jsonAcc, "Export password", "Import password"); err != nil {
+		t.Fatalf("Failed to import account: %v", err)
+	}
+	// Create a new account to sign transactions with
+	signer, err := am.NewAccount("Signer password")
+	if err != nil {
+		t.Fatalf("Failed to create signer account: %v", err)
+	}
+	txHash := common.HexToHash("0x0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef")
+
+	// Sign a transaction with a single authorization
+	if _, err := am.SignWithPassphrase(signer, "Signer password", txHash.Bytes()); err != nil {
+		t.Fatalf("Failed to sign with passphrase: %v", err)
+	}
+	// Sign a transaction with multiple manually cancelled authorizations
+	if err := am.Unlock(signer, "Signer password"); err != nil {
+		t.Fatalf("Failed to unlock account: %v", err)
+	}
+	if _, err := am.Sign(signer.Address, txHash.Bytes()); err != nil {
+		t.Fatalf("Failed to sign with unlocked account: %v", err)
+	}
+	if err := am.Lock(signer.Address); err != nil {
+		t.Fatalf("Failed to lock account: %v", err)
+	}
+	// Sign a transaction with multiple automatically cancelled authorizations
+	if err := am.TimedUnlock(signer, "Signer password", time.Second); err != nil {
+		t.Fatalf("Failed to time unlock account: %v", err)
+	}
+	if _, err := am.Sign(signer.Address, txHash.Bytes()); err != nil {
+		t.Fatalf("Failed to sign with time unlocked account: %v", err)
+	}
+}