Fix body nil checking in NewRequest

client.go

@@ -34,6 +34,7 @@ import (
 	"net/http"
 	"net/url"
 	"os"
+	"reflect"
 	"regexp"
 	"strconv"
 	"strings"
@@ -154,6 +155,10 @@ func getBodyReaderAndContentLength(rawBody interface{}) (ReaderFunc, int64, erro
 	var bodyReader ReaderFunc
 	var contentLength int64
 
+	if isNil(rawBody) {
+		return bodyReader, contentLength, nil
+	}
+
 	switch body := rawBody.(type) {
 	// If they gave us a function already, great! Use it.
 	case ReaderFunc:
@@ -772,3 +777,7 @@ func (c *Client) StandardClient() *http.Client {
 		Transport: &RoundTripper{Client: c},
 	}
 }
+
+func isNil(v interface{}) bool {
+	return v == nil || ((reflect.ValueOf(v).Kind() == reflect.Ptr || reflect.ValueOf(v).Kind() == reflect.Slice) && reflect.ValueOf(v).IsNil())
+}

client_test.go

@@ -842,3 +842,21 @@ func TestClient_StandardClient(t *testing.T) {
 		t.Fatalf("expected %v, got %v", client, v)
 	}
 }
+
+func Test_NewRequest(t *testing.T) {
+	req, err := NewRequest("GET", "localhost:1234", nil)
+	if err != nil {
+		t.Fatalf("failed to create a request: %s", err)
+	}
+
+	var b []byte
+	b = nil
+	r, err := NewRequest("GET", "localhost:1234", b)
+	if err != nil {
+		t.Fatalf("failed to create a request: %s", err)
+	}
+
+	if req.body != nil || r.body != nil {
+		t.Fatalf("expected nil body for both requests, got:%v %v", req.body, r.body)
+	}
+}