code review 6945065: encoding/json: don't panic marshaling anonymous non-str...

encoding/json: don't panic marshaling anonymous non-struct field

Add a check for this case and don't try to follow the anonymous
type's non-existent fields.

Fixes issue 4474.

[tkappler, 2012-12-16 15:06:00]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[rsc, 2012-12-17 00:37:40]

https://codereview.appspot.com/6945065/diff/4001/src/pkg/encoding/json/encode.go
File src/pkg/encoding/json/encode.go (right):

https://codereview.appspot.com/6945065/diff/4001/src/pkg/encoding/json/encode...
src/pkg/encoding/json/encode.go:621: if name != "" || !sf.Anonymous {
Can you do

|| sf.Type.Kind() != reflect.Struct

here?

[tkappler, 2012-12-17 20:45:09]

Hello rsc@golang.org (cc: golang-dev@googlegroups.com),

Please take another look.

[tkappler, 2012-12-17 20:48:47]

On 2012/12/17 00:37:40, rsc wrote:
>
https://codereview.appspot.com/6945065/diff/4001/src/pkg/encoding/json/encode.go
> File src/pkg/encoding/json/encode.go (right):
> 
>
https://codereview.appspot.com/6945065/diff/4001/src/pkg/encoding/json/encode...
> src/pkg/encoding/json/encode.go:621: if name != "" || !sf.Anonymous {
> Can you do
> 
> || sf.Type.Kind() != reflect.Struct
> 
> here?

Yep, that works. I like it better because it's one less branch. Also, I forgot
to handle tags, which comes now for free.

I just had to move up the code that follows pointers (ft = ft.Elem()) for
anonymous fields, because in that case we want to check sf.Type.Elem().Kind() !=
reflect.Struct.

[rsc, 2012-12-22 14:49:24]

LGTM

[rsc, 2012-12-22 14:54:14]

It looks like you need to complete a CLA as described at
http://golang.org/doc/contribute.html#copyright.

Thanks.

[tkappler, 2012-12-26 09:14:57]

On 2012/12/22 14:54:14, rsc wrote:
> It looks like you need to complete a CLA as described at
> http://golang.org/doc/contribute.html#copyright.

Submitted my CLA. Thanks!

[rsc, 2013-01-02 22:39:48]

*** Submitted as https://code.google.com/p/go/source/detail?r=94f706ea3818 ***

encoding/json: don't panic marshaling anonymous non-struct field

Add a check for this case and don't try to follow the anonymous
type's non-existent fields.

Fixes issue 4474.

R=rsc
CC=golang-dev
https://codereview.appspot.com/6945065

Committer: Russ Cox <rsc@golang.org>