updates: append(y,[]byte(z)...) -> append(y,z...)"

(more are possible but omitted for now as they are part of
specific tests where rather than changing what is there we
should probably expand the tests to cover the new case)

R=rsc, dvyukov
CC=golang-dev
https://golang.org/cl/5247058

src/pkg/bytes/bytes_test.go

@@ -829,7 +829,7 @@ var ReplaceTests = []ReplaceTest{
 
 func TestReplace(t *testing.T) {
 	for _, tt := range ReplaceTests {
-		in := append([]byte(tt.in), []byte("<spare>")...)
+		in := append([]byte(tt.in), "<spare>"...)
 		in = in[:len(tt.in)]
 		out := Replace(in, []byte(tt.old), []byte(tt.new), tt.n)
 		if s := string(out); s != tt.out {

src/pkg/exp/norm/normregtest.go

@@ -280,7 +280,7 @@ func PerformanceTest() {
 	success := make(chan bool, 1)
 	go func() {
 		buf := bytes.Repeat([]byte("\u035D"), 1024*1024)
-		buf = append(buf, []byte("\u035B")...)
+		buf = append(buf, "\u035B"...)
 		norm.NFC.Append(nil, buf...)
 		success <- true
 	}()

src/pkg/exp/norm/readwriter_test.go

@@ -23,7 +23,7 @@ var bufSizes = []int{1, 2, 3, 4, 5, 6, 7, 8, 100, 101, 102, 103, 4000, 4001, 400
 
 func readFunc(size int) appendFunc {
 	return func(f Form, out []byte, s string) []byte {
-		out = append(out, []byte(s)...)
+		out = append(out, s...)
 		r := f.Reader(bytes.NewBuffer(out))
 		buf := make([]byte, size)
 		result := []byte{}
@@ -46,7 +46,7 @@ func TestReader(t *testing.T) {
 
 func writeFunc(size int) appendFunc {
 	return func(f Form, out []byte, s string) []byte {
-		in := append(out, []byte(s)...)
+		in := append(out, s...)
 		result := new(bytes.Buffer)
 		w := f.Writer(result)
 		buf := make([]byte, size)

src/pkg/exp/ssh/messages.go

@@ -323,7 +323,7 @@ func marshal(msgType uint8, msg interface{}) []byte {
 			out = append(out, byte(len(s)>>16))
 			out = append(out, byte(len(s)>>8))
 			out = append(out, byte(len(s)))
-			out = append(out, []byte(s)...)
+			out = append(out, s...)
 		case reflect.Slice:
 			switch t.Elem().Kind() {
 			case reflect.Uint8:
@@ -354,7 +354,7 @@ func marshal(msgType uint8, msg interface{}) []byte {
 					if j != 0 {
 						out = append(out, ',')
 					}
-					out = append(out, []byte(field.Index(j).String())...)
+					out = append(out, field.Index(j).String()...)
 				}
 			default:
 				panic("slice of unknown type")

src/pkg/json/scanner_test.go

@@ -175,7 +175,7 @@ func TestNextValueBig(t *testing.T) {
 		t.Errorf("invalid rest: %d", len(rest))
 	}
 
-	item, rest, err = nextValue(append(jsonBig, []byte("HELLO WORLD")...), &scan)
+	item, rest, err = nextValue(append(jsonBig, "HELLO WORLD"...), &scan)
 	if err != nil {
 		t.Fatalf("nextValue extra: %s", err)
 	}

src/pkg/os/dir_plan9.go

@@ -295,6 +295,6 @@ func pstring(b []byte, s string) []byte {
 		panic(NewError("string too long"))
 	}
 	b = pbit16(b, uint16(len(s)))
-	b = append(b, []byte(s)...)
+	b = append(b, s...)
 	return b
 }

src/pkg/os/env.go

@@ -16,9 +16,9 @@ func Expand(s string, mapping func(string) string) string {
 	i := 0
 	for j := 0; j < len(s); j++ {
 		if s[j] == '$' && j+1 < len(s) {
-			buf = append(buf, []byte(s[i:j])...)
+			buf = append(buf, s[i:j]...)
 			name, w := getShellName(s[j+1:])
-			buf = append(buf, []byte(mapping(name))...)
+			buf = append(buf, mapping(name)...)
 			j += w
 			i = j + 1
 		}