types/known/structpb: preallocate map in AsMap
Change-Id: I4fe676418959c23055e91d99a07ee3be8d466e25
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/460215
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Michael Stapelberg <stapelberg@google.com>
diff --git a/cmd/protoc-gen-go/internal_gengo/well_known_types.go b/cmd/protoc-gen-go/internal_gengo/well_known_types.go
index 696dddb..47c4fa1 100644
--- a/cmd/protoc-gen-go/internal_gengo/well_known_types.go
+++ b/cmd/protoc-gen-go/internal_gengo/well_known_types.go
@@ -208,8 +208,7 @@
"google.golang.org/protobuf/encoding/protojson" package
ensures that they will be serialized as their JSON equivalent.
-
- Conversion to and from a Go interface
+ # Conversion to and from a Go interface
The standard Go "encoding/json" package has functionality to serialize
arbitrary types to a large degree. The Value.AsInterface, Struct.AsMap, and
@@ -222,8 +221,7 @@
forms back as Value, Struct, and ListValue messages, use the NewStruct,
NewList, and NewValue constructor functions.
-
- Example usage
+ # Example usage
Consider the following example JSON object:
@@ -282,7 +280,6 @@
... // handle error
}
... // make use of m as a *structpb.Value
-
`
case genid.File_google_protobuf_field_mask_proto:
return ` Package fieldmaskpb contains generated types for ` + genid.File_google_protobuf_field_mask_proto + `.
@@ -656,8 +653,9 @@
g.P("// AsMap converts x to a general-purpose Go map.")
g.P("// The map values are converted by calling Value.AsInterface.")
g.P("func (x *Struct) AsMap() map[string]interface{} {")
- g.P(" vs := make(map[string]interface{})")
- g.P(" for k, v := range x.GetFields() {")
+ g.P(" f := x.GetFields()")
+ g.P(" vs := make(map[string]interface{}, len(f))")
+ g.P(" for k, v := range f {")
g.P(" vs[k] = v.AsInterface()")
g.P(" }")
g.P(" return vs")
@@ -693,8 +691,9 @@
g.P("// AsSlice converts x to a general-purpose Go slice.")
g.P("// The slice elements are converted by calling Value.AsInterface.")
g.P("func (x *ListValue) AsSlice() []interface{} {")
- g.P(" vs := make([]interface{}, len(x.GetValues()))")
- g.P(" for i, v := range x.GetValues() {")
+ g.P(" vals := x.GetValues()")
+ g.P(" vs := make([]interface{}, len(vals))")
+ g.P(" for i, v := range vals {")
g.P(" vs[i] = v.AsInterface()")
g.P(" }")
g.P(" return vs")
diff --git a/types/known/structpb/struct.pb.go b/types/known/structpb/struct.pb.go
index 882b0af..89bdf57 100644
--- a/types/known/structpb/struct.pb.go
+++ b/types/known/structpb/struct.pb.go
@@ -44,8 +44,7 @@
// "google.golang.org/protobuf/encoding/protojson" package
// ensures that they will be serialized as their JSON equivalent.
//
-//
-// Conversion to and from a Go interface
+// # Conversion to and from a Go interface
//
// The standard Go "encoding/json" package has functionality to serialize
// arbitrary types to a large degree. The Value.AsInterface, Struct.AsMap, and
@@ -58,8 +57,7 @@
// forms back as Value, Struct, and ListValue messages, use the NewStruct,
// NewList, and NewValue constructor functions.
//
-//
-// Example usage
+// # Example usage
//
// Consider the following example JSON object:
//
@@ -118,7 +116,6 @@
// ... // handle error
// }
// ... // make use of m as a *structpb.Value
-//
package structpb
import (
@@ -218,8 +215,9 @@
// AsMap converts x to a general-purpose Go map.
// The map values are converted by calling Value.AsInterface.
func (x *Struct) AsMap() map[string]interface{} {
- vs := make(map[string]interface{})
- for k, v := range x.GetFields() {
+ f := x.GetFields()
+ vs := make(map[string]interface{}, len(f))
+ for k, v := range f {
vs[k] = v.AsInterface()
}
return vs
@@ -596,8 +594,9 @@
// AsSlice converts x to a general-purpose Go slice.
// The slice elements are converted by calling Value.AsInterface.
func (x *ListValue) AsSlice() []interface{} {
- vs := make([]interface{}, len(x.GetValues()))
- for i, v := range x.GetValues() {
+ vals := x.GetValues()
+ vs := make([]interface{}, len(vals))
+ for i, v := range vals {
vs[i] = v.AsInterface()
}
return vs
