Fix a PHP Notice in REST API responses

[pento]

Description

As described in #6575, there's a PHP notice when adding the block_format to post responses.

We can fix this by removing the is_array() check, is isset() can check multi-dimensional arrays correctly.

[gziolo]

1. REST_Blocks_Controller_Test::test_create_item
   Failed asserting that two strings are equal.
   --- Expected
   +++ Actual
   @@ @@
   -'

   Wow!

   '
   +'0!-- wp:core/paragraph -->

   Wow!

   '
   /home/travis/build/WordPress/gutenberg/phpunit/class-rest-blocks-controller-test.php:136
   /home/travis/.phpbrew/php/php-5.2.17/lib/php/phpunit/phpunit.php:46
2. REST_Blocks_Controller_Test::test_update_item
   Failed asserting that two strings are equal.
   --- Expected
   +++ Actual
   @@ @@
   -'

   Nice!

   '
   +'0!-- wp:core/paragraph -->

   Nice!

   '
   /home/travis/build/WordPress/gutenberg/phpunit/class-rest-blocks-controller-test.php:165
   /home/travis/.phpbrew/php/php-5.2.17/lib/php/phpunit/phpunit.php:46
3. REST_Blocks_Controller_Test::test_delete_item
   Failed asserting that two strings are equal.
   --- Expected
   +++ Actual
   @@ @@
   -'

   Hello!

   '
   +'0!-- wp:core/paragraph -->

   Hello!

   '
   /home/travis/build/WordPress/gutenberg/phpunit/class-rest-blocks-controller-test.php:193
   /home/travis/.phpbrew/php/php-5.2.17/lib/php/phpunit/phpunit.php:46
   FAILURES!
   Tests: 175, Assertions: 287, Failures: 3, Skipped: 9.

PHPUnit doesn't like it :)

[ocean90]

The is_array() was added for PHP 5.2 compat, see 75e7234.

[gziolo]

So you need another isset in that case in additon to is_array check ...

[gziolo]

It fixes the issue.

[pento]

PHP 5.2 is the worst.

[ZebulanStanphill]

Off-topic, but why does WordPress still support such old PHP versions? PHP 5.5 and earlier is not even officially supported anymore. Couldn't the dev team announce that PHP 5.5 and earlier versions will stop being supported in WordPress 5.2 or something, in order to give people time to update? I've heard some people complain that WordPress is actually holding back adoption of newer PHP versions by continuing to support really old PHP versions.

[danielbachhuber]

Hi @SuperGeniusZeb,

Let's keep the conversation on-topic. For discussion of minimum PHP version, please this existing thread https://core.trac.wordpress.org/ticket/33381