Re: [PATCH iproute2-next] json_writer: fix pretty printing of arrays

[Hadrien Patte <hadrien.patte@protonmail.com>]

On Fri, 23 Oct 2026 18:13:02 -0700
Stephen Hemminger <stephen@networkplumber.org> wrote:

> Putting all the array elements on oneline is easier to read and more compact.
> What does python do?

My current patch actually contains two separate changes:

1. A fix for arrays of objects. Scalar arrays render fine on a single
   line, but when the elements are objects, which contain newlines, the
   brackets and separators end up glued to them and the indentation
   levels of opening and closing brackets are off:

   # ip -j -p addr show dev lo
   [ {
           "ifindex": 1,
           "ifname": "lo",
           "flags": [ "LOOPBACK","UP","LOWER_UP" ],
           ...
           "addr_info": [ {
                   "family": "inet",
                   "local": "127.0.0.1",
                   ...
               },{
                   "family": "inet6",
                   "local": "::1",
                   ...
               } ]
       } ]

2. Putting each element of scalar arrays on its own line. This is a
   style change rather than a fix, though it is consistent with common
   JSON pretty-printers such as jq or python's json.dumps.

I'm happy to send a v2 that only keeps the first part, leaving scalar
arrays in their current single-line form if you prefer.

Thanks,
Hadrien