mojo-json-patch.pm

package Mojo::JSON::Patch;
use Mojo::Base 'Mojo::JSON::Pointer';

use Carp 'croak';
use Mojo::Path;

sub set {
  my $self = shift;
  my $path = Mojo::Path->new(shift);
  my $val  = shift;

  croak 'Non-exising JSON node' unless $self->contains("$path");

  my $leaf = pop @$path; # TODO: Should this happen before or after contains() ?
  my $parent = $self->get("$path");

  if (ref $parent eq 'ARRAY') {
    $parent->[$leaf] = $val;
  }
  elsif (ref $parent eq 'HASH') {
    $parent->{$leaf} = $val;
  }

  return $self;
}

package main;
use Test::More;

my $p = Mojo::JSON::Patch->new({foo => {bar => [24, 42]}});

is $p->get('/foo/bar/0'), 24, 'get original value';
is $p->set('/foo/bar/1', 54), $p, 'set new value';
is $p->get('/foo/bar/1'), 54, 'get new value';

eval { $p->set('/foo/bar/3', 54) };
like $@, qr{Non-exising}, 'non exising';

is $p->set('/foo/bar', [64]), $p, 'set /foo/bar';
is $p->get('/foo/bar/0'), 64, 'get new array';

done_testing;