client.baseRetryPolicy check if response is nil before accessing attributes

client.go

@@ -28,6 +28,7 @@ import (
 	"bytes"
 	"context"
 	"crypto/x509"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -492,6 +493,11 @@ func baseRetryPolicy(resp *http.Response, err error) (bool, error) {
 		return true, nil
 	}
 
+	// check if is nil to make below attributes access safe
+	if resp == nil {
+		return false, errors.New("response is nil")
+	}
+
 	// 429 Too Many Requests is recoverable. Sometimes the server puts
 	// a Retry-After response header to indicate when the server is
 	// available to start processing request from client.

client_test.go

@@ -978,3 +978,16 @@ func TestClient_StandardClient(t *testing.T) {
 		t.Fatalf("expected %v, got %v", client, v)
 	}
 }
+
+func TestClient_baseRetryPolicy(t *testing.T) {
+	t.Parallel()
+	var response *http.Response = nil
+
+	ok, err := baseRetryPolicy(response, nil)
+	if ok {
+		t.Fatalf("expected %v, got %v", false, ok)
+	}
+	if err == nil {
+		t.Fatalf("should error")
+	}
+}