Sync changes to internal version:

	        	- use append built-in
                        - remove NewT from commentary
	                - some idiom changes

R=r
CC=golang-dev
http://codereview.appspot.com/2926042

compiler/generator/generator.go

@@ -71,14 +71,7 @@ var plugins []Plugin
 // RegisterPlugin installs a (second-order) plugin to be run when the Go output is generated.
 // It is typically called during initialization.
 func RegisterPlugin(p Plugin) {
-	n := len(plugins)
-	if cap(plugins) == n {
-		nplugins := make([]Plugin, n, n+10) // very unlikely to need more than this
-		copy(nplugins, plugins)
-		plugins = nplugins
-	}
-	plugins = plugins[0 : n+1]
-	plugins[n] = p
+	plugins = append(plugins, p)
 }
 
 // Each type we import as a protocol buffer (other than FileDescriptorProto) needs
@@ -438,14 +431,7 @@ func addDescriptor(sl []*Descriptor, desc *descriptor.DescriptorProto, parent *D
 		d.ext[i] = &ExtensionDescriptor{common{File: file}, field, d}
 	}
 
-	if len(sl) == cap(sl) {
-		nsl := make([]*Descriptor, len(sl), 2*len(sl))
-		copy(nsl, sl)
-		sl = nsl
-	}
-	sl = sl[0 : len(sl)+1]
-	sl[len(sl)-1] = d
-	return sl
+	return append(sl, d)
 }
 
 // Return a slice of all the Descriptors defined within this file
@@ -469,14 +455,7 @@ func wrapThisDescriptor(sl []*Descriptor, desc *descriptor.DescriptorProto, pare
 
 // Construct the EnumDescriptor and add it to the slice
 func addEnumDescriptor(sl []*EnumDescriptor, desc *descriptor.EnumDescriptorProto, parent *Descriptor, file *descriptor.FileDescriptorProto) []*EnumDescriptor {
-	if len(sl) == cap(sl) {
-		nsl := make([]*EnumDescriptor, len(sl), 2*len(sl))
-		copy(nsl, sl)
-		sl = nsl
-	}
-	sl = sl[0 : len(sl)+1]
-	sl[len(sl)-1] = &EnumDescriptor{common{File: file}, desc, parent, nil}
-	return sl
+	return append(sl, &EnumDescriptor{common{File: file}, desc, parent, nil})
 }
 
 // Return a slice of all the EnumDescriptors defined within this file

compiler/testdata/extension_test.go

@@ -42,8 +42,9 @@ import (
 )
 
 func TestSingleFieldExtension(t *testing.T) {
-	bm := &base.BaseMessage{}
-	bm.Height = proto.Int32(178)
+	bm := &base.BaseMessage{
+		Height: proto.Int32(178),
+	}
 
 	// Use extension within scope of another type.
 	vol := proto.Uint32(11)
@@ -55,7 +56,7 @@ func TestSingleFieldExtension(t *testing.T) {
 	if err != nil {
 		t.Fatal("Failed encoding message with extension:", err)
 	}
-	bm_new := &base.BaseMessage{}
+	bm_new := new(base.BaseMessage)
 	if err := proto.Unmarshal(buf, bm_new); err != nil {
 		t.Fatal("Failed decoding message with extension:", err)
 	}
@@ -76,8 +77,9 @@ func TestSingleFieldExtension(t *testing.T) {
 }
 
 func TestMessageExtension(t *testing.T) {
-	bm := &base.BaseMessage{}
-	bm.Height = proto.Int32(179)
+	bm := &base.BaseMessage{
+		Height: proto.Int32(179),
+	}
 
 	// Use extension that is itself a message.
 	um := &user.UserMessage{
@@ -92,7 +94,7 @@ func TestMessageExtension(t *testing.T) {
 	if err != nil {
 		t.Fatal("Failed encoding message with extension:", err)
 	}
-	bm_new := &base.BaseMessage{}
+	bm_new := new(base.BaseMessage)
 	if err := proto.Unmarshal(buf, bm_new); err != nil {
 		t.Fatal("Failed decoding message with extension:", err)
 	}
@@ -116,8 +118,9 @@ func TestMessageExtension(t *testing.T) {
 }
 
 func TestTopLevelExtension(t *testing.T) {
-	bm := &base.BaseMessage{}
-	bm.Height = proto.Int32(179)
+	bm := &base.BaseMessage{
+		Height: proto.Int32(179),
+	}
 
 	width := proto.Int32(17)
 	err := proto.SetExtension(bm, user.E_Width, width)
@@ -128,7 +131,7 @@ func TestTopLevelExtension(t *testing.T) {
 	if err != nil {
 		t.Fatal("Failed encoding message with extension:", err)
 	}
-	bm_new := &base.BaseMessage{}
+	bm_new := new(base.BaseMessage)
 	if err := proto.Unmarshal(buf, bm_new); err != nil {
 		t.Fatal("Failed decoding message with extension:", err)
 	}

proto/lib.go

@@ -43,8 +43,6 @@
 	  - The zero value for a struct is its correct initialization state.
 		All desired fields must be set before marshaling.
 	  - A Reset() method will restore a protobuf struct to its zero state.
-	  - Each type T has a method NewT() to create a new instance. It
-		is equivalent to new(T).
 	  - Non-repeated fields are pointers to the values; nil means unset.
 		That is, optional or required field int32 f becomes F *int32.
 	  - Repeated fields are slices.
@@ -112,9 +110,6 @@
 		func (this *Test) Reset() {
 			*this = Test{}
 		}
-		func NewTest() *Test {
-			return new(Test)
-		}
 		const Default_Test_Type int32 = 77
 
 		type Test_OptionalGroup struct {
@@ -124,9 +119,6 @@
 		func (this *Test_OptionalGroup) Reset() {
 			*this = Test_OptionalGroup{}
 		}
-		func NewTest_OptionalGroup() *Test_OptionalGroup {
-			return new(Test_OptionalGroup)
-		}
 
 		func init() {
 			proto.RegisterEnum("example.FOO", FOO_name, FOO_value)
@@ -144,25 +136,25 @@
 		)
 
 		func main() {
-			test := &example.Test {
+			test := &example.Test{
 				Label: proto.String("hello"),
 				Type: proto.Int32(17),
-				Optionalgroup: &example.Test_OptionalGroup {
+				Optionalgroup: &example.Test_OptionalGroup{
 					RequiredField: proto.String("good bye"),
 				},
 			}
 			data, err := proto.Marshal(test)
 			if err != nil {
-				log.Exitln("marshaling error:", err)
+				log.Exit("marshaling error:", err)
 			}
-			newTest := example.NewTest()
+			newTest := new(example.Test)
 			err = proto.Unmarshal(data, newTest)
 			if err != nil {
-				log.Exitln("unmarshaling error:", err)
+				log.Exit("unmarshaling error:", err)
 			}
 			// Now test and newTest contain the same data.
 			if proto.GetString(test.Label) != proto.GetString(newTest.Label) {
-				log.Exitf("data mismatch %q %q", proto.GetString(test.Label), proto.GetString(newTest.Label))
+				log.Exit("data mismatch %q %q", proto.GetString(test.Label), proto.GetString(newTest.Label))
 			}
 			// etc.
 		}