lib/random: unify random string generation into random.String

This was factored from fstest as we were including the testing
enviroment into the main binary because of it.

This was causing opening the browser to fail because of 8243ff8bc8.

backend/cache/cache_internal_test.go

@@ -33,6 +33,7 @@ import (
 	"github.com/rclone/rclone/fs/object"
 	"github.com/rclone/rclone/fs/rc"
 	"github.com/rclone/rclone/fstest"
+	"github.com/rclone/rclone/lib/random"
 	"github.com/rclone/rclone/vfs"
 	"github.com/rclone/rclone/vfs/vfsflags"
 	"github.com/stretchr/testify/assert"
@@ -355,8 +356,8 @@ func TestInternalCachedUpdatedContentMatches(t *testing.T) {
 		testData2, err = base64.StdEncoding.DecodeString(cryptedText2Base64)
 		require.NoError(t, err)
 	} else {
-		testData1 = []byte(fstest.RandomString(100))
-		testData2 = []byte(fstest.RandomString(200))
+		testData1 = []byte(random.String(100))
+		testData2 = []byte(random.String(200))
 	}
 
 	// write the object

backend/googlephotos/googlephotos_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/rclone/rclone/fs"
 	"github.com/rclone/rclone/fs/hash"
 	"github.com/rclone/rclone/fstest"
+	"github.com/rclone/rclone/lib/random"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -55,7 +56,7 @@ func TestIntegration(t *testing.T) {
 	require.NoError(t, err)
 
 	t.Run("CreateAlbum", func(t *testing.T) {
-		albumName := "album/rclone-test-" + fstest.RandomString(24)
+		albumName := "album/rclone-test-" + random.String(24)
 		err = f.Mkdir(ctx, albumName)
 		require.NoError(t, err)
 		remote := albumName + "/" + fileNameAlbum

cmd/cmd.go

@@ -9,6 +9,7 @@ package cmd
 import (
 	"fmt"
 	"log"
+	"math/rand"
 	"os"
 	"os/exec"
 	"path"
@@ -492,6 +493,7 @@ func AddBackendFlags() {
 
 // Main runs rclone interpreting flags and commands out of os.Args
 func Main() {
+	rand.Seed(time.Now().Unix())
 	setupRootCommand(Root)
 	AddBackendFlags()
 	if err := Root.Execute(); err != nil {

cmd/info/info.go

@@ -18,7 +18,7 @@ import (
 	"github.com/rclone/rclone/fs"
 	"github.com/rclone/rclone/fs/hash"
 	"github.com/rclone/rclone/fs/object"
-	"github.com/rclone/rclone/fstest"
+	"github.com/rclone/rclone/lib/random"
 	"github.com/spf13/cobra"
 )
 
@@ -118,7 +118,7 @@ func (r *results) Print() {
 
 // writeFile writes a file with some random contents
 func (r *results) writeFile(path string) (fs.Object, error) {
-	contents := fstest.RandomString(50)
+	contents := random.String(50)
 	src := object.NewStaticObjectInfo(path, time.Now(), int64(len(contents)), true, nil, r.f)
 	return r.f.Put(r.ctx, bytes.NewBufferString(contents), src)
 }

fs/operations/multithread_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/rclone/rclone/fs/accounting"
+	"github.com/rclone/rclone/lib/random"
 
 	"github.com/rclone/rclone/fs"
 	"github.com/rclone/rclone/fstest"
@@ -52,7 +53,7 @@ func TestMultithreadCopy(t *testing.T) {
 	} {
 		t.Run(fmt.Sprintf("%+v", test), func(t *testing.T) {
 			var err error
-			contents := fstest.RandomString(test.size)
+			contents := random.String(test.size)
 			t1 := fstest.Time("2001-02-03T04:05:06.499999999Z")
 			file1 := r.WriteObject(context.Background(), "file1", contents, t1)
 			fstest.CheckItems(t, r.Fremote, file1)

fs/operations/operations.go

@@ -8,7 +8,6 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
-	"math/rand"
 	"path"
 	"path/filepath"
 	"sort"
@@ -28,6 +27,7 @@ import (
 	"github.com/rclone/rclone/fs/march"
 	"github.com/rclone/rclone/fs/object"
 	"github.com/rclone/rclone/fs/walk"
+	"github.com/rclone/rclone/lib/random"
 	"github.com/rclone/rclone/lib/readers"
 	"golang.org/x/sync/errgroup"
 )
@@ -1666,7 +1666,7 @@ func moveOrCopyFile(ctx context.Context, fdst fs.Fs, fsrc fs.Fs, dstFileName str
 	// to avoid issues with certain remotes and avoid file deletion.
 	if !cp && fdst.Name() == fsrc.Name() && fdst.Features().CaseInsensitive && dstFileName != srcFileName && strings.ToLower(dstFilePath) == strings.ToLower(srcFilePath) {
 		// Create random name to temporarily move file to
-		tmpObjName := dstFileName + "-rclone-move-" + random(8)
+		tmpObjName := dstFileName + "-rclone-move-" + random.String(8)
 		_, err := fdst.NewObject(ctx, tmpObjName)
 		if err != fs.ErrorObjectNotFound {
 			if err == nil {
@@ -1730,17 +1730,6 @@ func moveOrCopyFile(ctx context.Context, fdst fs.Fs, fsrc fs.Fs, dstFileName str
 	return err
 }
 
-// random generates a pseudorandom alphanumeric string
-func random(length int) string {
-	randomOutput := make([]byte, length)
-	possibleCharacters := "123567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
-	rand.Seed(time.Now().Unix())
-	for i := range randomOutput {
-		randomOutput[i] = possibleCharacters[rand.Intn(len(possibleCharacters))]
-	}
-	return string(randomOutput)
-}
-
 // MoveFile moves a single file possibly to a new name
 func MoveFile(ctx context.Context, fdst fs.Fs, fsrc fs.Fs, dstFileName string, srcFileName string) (err error) {
 	return moveOrCopyFile(ctx, fdst, fsrc, dstFileName, srcFileName, false)

fs/rc/rcserver/rcserver.go

@@ -95,6 +95,8 @@ func (s *Server) Serve() error {
 		// Don't open browser if serving in testing environment.
 		if flag.Lookup("test.v") == nil {
 			_ = open.Start(openURL.String())
+		} else {
+			fs.Errorf(nil, "Not opening browser in testing environment")
 		}
 	}
 	return nil

fstest/fstest.go

@@ -27,6 +27,7 @@ import (
 	"github.com/rclone/rclone/fs/config"
 	"github.com/rclone/rclone/fs/hash"
 	"github.com/rclone/rclone/fs/walk"
+	"github.com/rclone/rclone/lib/random"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/text/unicode/norm"
@@ -357,24 +358,6 @@ func Time(timeString string) time.Time {
 	return t
 }
 
-// RandomString create a random string for test purposes
-func RandomString(n int) string {
-	const (
-		vowel     = "aeiou"
-		consonant = "bcdfghjklmnpqrstvwxyz"
-		digit     = "0123456789"
-	)
-	pattern := []string{consonant, vowel, consonant, vowel, consonant, vowel, consonant, digit}
-	out := make([]byte, n)
-	p := 0
-	for i := range out {
-		source := pattern[p]
-		p = (p + 1) % len(pattern)
-		out[i] = source[rand.Intn(len(source))]
-	}
-	return string(out)
-}
-
 // LocalRemote creates a temporary directory name for local remotes
 func LocalRemote() (path string, err error) {
 	path, err = ioutil.TempDir("", "rclone")
@@ -403,7 +386,7 @@ func RandomRemoteName(remoteName string) (string, string, error) {
 		if !strings.HasSuffix(remoteName, ":") {
 			remoteName += "/"
 		}
-		leafName = "rclone-test-" + RandomString(24)
+		leafName = "rclone-test-" + random.String(24)
 		if !MatchTestRemote.MatchString(leafName) {
 			log.Fatalf("%q didn't match the test remote name regexp", leafName)
 		}
@@ -432,7 +415,7 @@ func RandomRemote(remoteName string, subdir bool) (fs.Fs, string, func(), error)
 		if err != nil {
 			return nil, "", nil, err
 		}
-		remoteName += "/rclone-test-subdir-" + RandomString(8)
+		remoteName += "/rclone-test-subdir-" + random.String(8)
 	}
 
 	remote, err := fs.NewFs(remoteName)

fstest/fstests/fstests.go

@@ -31,6 +31,7 @@ import (
 	"github.com/rclone/rclone/fs/operations"
 	"github.com/rclone/rclone/fs/walk"
 	"github.com/rclone/rclone/fstest"
+	"github.com/rclone/rclone/lib/random"
 	"github.com/rclone/rclone/lib/readers"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -157,7 +158,7 @@ func testPut(t *testing.T, f fs.Fs, file *fstest.Item) (string, fs.Object) {
 		contents   string
 	)
 	retry(t, "Put", func() error {
-		contents = fstest.RandomString(100)
+		contents = random.String(100)
 		buf := bytes.NewBufferString(contents)
 		uploadHash = hash.NewMultiHasher()
 		in := io.TeeReader(buf, uploadHash)
@@ -557,7 +558,7 @@ func Run(t *testing.T, opt *Opt) {
 
 			const N = 5 * 1024
 			// Read N bytes then produce an error
-			contents := fstest.RandomString(N)
+			contents := random.String(N)
 			buf := bytes.NewBufferString(contents)
 			er := &errorReader{errors.New("potato")}
 			in := io.MultiReader(buf, er)
@@ -1322,7 +1323,7 @@ func Run(t *testing.T, opt *Opt) {
 			// TestObjectUpdate tests that Update works
 			t.Run("ObjectUpdate", func(t *testing.T) {
 				skipIfNotOk(t)
-				contents := fstest.RandomString(200)
+				contents := random.String(200)
 				buf := bytes.NewBufferString(contents)
 				hash := hash.NewMultiHasher()
 				in := io.TeeReader(buf, hash)
@@ -1507,7 +1508,7 @@ func Run(t *testing.T, opt *Opt) {
 					contentSize = 100
 				)
 				retry(t, "PutStream", func() error {
-					contents := fstest.RandomString(contentSize)
+					contents := random.String(contentSize)
 					buf := bytes.NewBufferString(contents)
 					uploadHash = hash.NewMultiHasher()
 					in := io.TeeReader(buf, uploadHash)
@@ -1564,7 +1565,7 @@ func Run(t *testing.T, opt *Opt) {
 					assert.Nil(t, recover(), "Fs.Put() should not panic when src.Size() == -1")
 				}()
 
-				contents := fstest.RandomString(100)
+				contents := random.String(100)
 				in := bytes.NewBufferString(contents)
 
 				obji := object.NewStaticObjectInfo("unknown-size-put.txt", fstest.Time("2002-02-03T04:05:06.499999999Z"), -1, true, nil, nil)
@@ -1587,7 +1588,7 @@ func Run(t *testing.T, opt *Opt) {
 					assert.Nil(t, recover(), "Object.Update() should not panic when src.Size() == -1")
 				}()
 
-				newContents := fstest.RandomString(200)
+				newContents := random.String(200)
 				in := bytes.NewBufferString(newContents)
 
 				obj := findObject(t, remote, unknownSizeUpdateFile.Path)

lib/random/random.go

@@ -0,0 +1,22 @@
+// Package random holds a few functions for working with random numbers
+package random
+
+import "math/rand"
+
+// String create a random string for test purposes
+func String(n int) string {
+	const (
+		vowel     = "aeiou"
+		consonant = "bcdfghjklmnpqrstvwxyz"
+		digit     = "0123456789"
+	)
+	pattern := []string{consonant, vowel, consonant, vowel, consonant, vowel, consonant, digit}
+	out := make([]byte, n)
+	p := 0
+	for i := range out {
+		source := pattern[p]
+		p = (p + 1) % len(pattern)
+		out[i] = source[rand.Intn(len(source))]
+	}
+	return string(out)
+}

lib/random/random_test.go

@@ -0,0 +1,13 @@
+package random
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestString(t *testing.T) {
+	for i := 0; i < 100; i++ {
+		assert.Equal(t, i, len(String(i)))
+	}
+}

vfs/test_vfs/test_vfs.go

@@ -18,6 +18,7 @@ import (
 	"time"
 
 	"github.com/rclone/rclone/lib/file"
+	"github.com/rclone/rclone/lib/random"
 )
 
 var (
@@ -35,24 +36,6 @@ func init() {
 
 }
 
-// RandomString create a random string for test purposes
-func RandomString(n int) string {
-	const (
-		vowel     = "aeiou"
-		consonant = "bcdfghjklmnpqrstvwxyz"
-		digit     = "0123456789"
-	)
-	pattern := []string{consonant, vowel, consonant, vowel, consonant, vowel, consonant, digit}
-	out := make([]byte, n)
-	p := 0
-	for i := range out {
-		source := pattern[p]
-		p = (p + 1) % len(pattern)
-		out[i] = source[rand.Intn(len(source))]
-	}
-	return string(out)
-}
-
 // Test contains stats about the running test which work for files or
 // directories
 type Test struct {
@@ -71,7 +54,7 @@ type Test struct {
 func NewTest(Dir string) *Test {
 	t := &Test{
 		dir:    Dir,
-		name:   RandomString(*nameLength),
+		name:   random.String(*nameLength),
 		isDir:  rand.Intn(2) == 0,
 		number: atomic.AddInt32(&testNumber, 1),
 		timer:  time.NewTimer(*timeout),
@@ -168,7 +151,7 @@ func (t *Test) rename() {
 		return
 	}
 	t.logf("rename")
-	NewName := RandomString(*nameLength)
+	NewName := random.String(*nameLength)
 	newPath := path.Join(t.dir, NewName)
 	err := os.Rename(t.path(), newPath)
 	if err != nil {