Merge branch 'philpearl-master'

helpers.go

@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"net/http"
 	"strconv"
+	"unsafe"
 
 	"github.com/mailru/easyjson/jlexer"
 	"github.com/mailru/easyjson/jwriter"
@@ -36,9 +37,17 @@ type UnknownsMarshaler interface {
 	MarshalUnknowns(w *jwriter.Writer, first bool)
 }
 
+func isNilInterface(i interface{}) bool {
+	return (*[2]uintptr)(unsafe.Pointer(&i))[1] == 0
+}
+
 // Marshal returns data as a single byte slice. Method is suboptimal as the data is likely to be copied
 // from a chain of smaller chunks.
 func Marshal(v Marshaler) ([]byte, error) {
+	if isNilInterface(v) {
+		return nullBytes, nil
+	}
+
 	w := jwriter.Writer{}
 	v.MarshalEasyJSON(&w)
 	return w.BuildBytes()
@@ -46,6 +55,10 @@ func Marshal(v Marshaler) ([]byte, error) {
 
 // MarshalToWriter marshals the data to an io.Writer.
 func MarshalToWriter(v Marshaler, w io.Writer) (written int, err error) {
+	if isNilInterface(v) {
+		return w.Write(nullBytes)
+	}
+
 	jw := jwriter.Writer{}
 	v.MarshalEasyJSON(&jw)
 	return jw.DumpTo(w)
@@ -56,6 +69,13 @@ func MarshalToWriter(v Marshaler, w io.Writer) (written int, err error) {
 // false if an error occurred before any http.ResponseWriter methods were actually
 // invoked (in this case a 500 reply is possible).
 func MarshalToHTTPResponseWriter(v Marshaler, w http.ResponseWriter) (started bool, written int, err error) {
+	if isNilInterface(v) {
+		w.Header().Set("Content-Type", "application/json")
+		w.Header().Set("Content-Length", strconv.Itoa(len(nullBytes)))
+		written, err = w.Write(nullBytes)
+		return true, written, err
+	}
+
 	jw := jwriter.Writer{}
 	v.MarshalEasyJSON(&jw)
 	if jw.Error != nil {

helpers_test.go

@@ -0,0 +1,12 @@
+package easyjson
+
+import "testing"
+
+func BenchmarkNilCheck(b *testing.B) {
+	var a *int
+	for i := 0; i < b.N; i++ {
+		if !isNilInterface(a) {
+			b.Fatal("expected it to be nil")
+		}
+	}
+}

tests/basic_test.go

@@ -1,6 +1,8 @@
 package tests
 
 import (
+	"bytes"
+	"net/http/httptest"
 	"reflect"
 	"testing"
 
@@ -267,3 +269,35 @@ func TestMethodsNoGenerated(t *testing.T) {
 		}
 	}
 }
+
+func TestNil(t *testing.T) {
+	var p *PrimitiveTypes
+
+	data, err := easyjson.Marshal(p)
+	if err != nil {
+		t.Errorf("easyjson.Marshal() error: %v", err)
+	}
+	if string(data) != "null" {
+		t.Errorf("Wanted null, got %q", string(data))
+	}
+
+	var b bytes.Buffer
+	if n, err := easyjson.MarshalToWriter(p, &b); err != nil || n != 4 {
+		t.Errorf("easyjson.MarshalToWriter() error: %v, written %d", err, n)
+	}
+
+	if s := b.String(); s != "null" {
+		t.Errorf("Wanted null, got %q", s)
+	}
+
+	w := httptest.NewRecorder()
+	started, written, err := easyjson.MarshalToHTTPResponseWriter(p, w)
+	if !started || written != 4 || err != nil {
+		t.Errorf("easyjson.MarshalToHTTPResponseWriter() error: %v, written %d, started %t",
+			err, written, started)
+	}
+
+	if s := w.Body.String(); s != "null" {
+		t.Errorf("Wanted null, got %q", s)
+	}
+}