XML-RPC: Fatal TypeError when the fields argument is not an array

[josephscott]

https://core.trac.wordpress.org/ticket/65983

AI assistance: Yes
Tool(s): Claude
Model(s): Fable 5
Used for: It wrote the tests.

---

This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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Props josephscott, westonruter.

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[github-actions]

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[westonruter]

Confirming that the tests are “load bearing” when run against trunk:

...............................................................  63 / 348 ( 18%)
............................................................... 126 / 348 ( 36%)
.........................................................E..... 189 / 348 ( 54%)
E....E.......F....E.....F..E.......E........................E.. 252 / 348 ( 72%)
.....E......................................................... 315 / 348 ( 90%)
.................................                               348 / 348 (100%)

Time: 00:11.630, Memory: 243.50 MB

There were 8 errors:

1) Tests_XMLRPC_wp_getPost::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:973
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:1963
/var/www/tests/phpunit/tests/xmlrpc/wp/getPost.php:157

2) Tests_XMLRPC_wp_getPostType::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:1040
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:4603
/var/www/tests/phpunit/tests/xmlrpc/wp/getPostType.php:135

3) Tests_XMLRPC_wp_getPostTypes::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:1040
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:4659
/var/www/tests/phpunit/tests/xmlrpc/wp/getPostTypes.php:52

4) Tests_XMLRPC_wp_getProfile::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:1262
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:2880
/var/www/tests/phpunit/tests/xmlrpc/wp/getProfile.php:57

5) Tests_XMLRPC_wp_getTaxonomies::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:828
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:2656
/var/www/tests/phpunit/tests/xmlrpc/wp/getTaxonomies.php:29

6) Tests_XMLRPC_wp_getTaxonomy::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:828
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:2597
/var/www/tests/phpunit/tests/xmlrpc/wp/getTaxonomy.php:87

7) Tests_XMLRPC_wp_getUser::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:1262
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:2741
/var/www/tests/phpunit/tests/xmlrpc/wp/getUser.php:150

8) Tests_XMLRPC_wp_getUsers::test_non_array_fields_returns_error
TypeError: in_array(): Argument #2 ($haystack) must be of type array, string given

/var/www/src/wp-includes/class-wp-xmlrpc-server.php:1262
/var/www/src/wp-includes/class-wp-xmlrpc-server.php:2828
/var/www/tests/phpunit/tests/xmlrpc/wp/getUsers.php:137

--

There were 2 failures:

1) Tests_XMLRPC_wp_getPosts::test_non_array_fields_returns_error
Failed asserting that Array () is an instance of class "IXR_Error".

/var/www/tests/phpunit/includes/abstract-testcase.php:909
/var/www/tests/phpunit/tests/xmlrpc/wp/getPosts.php:183

2) Tests_XMLRPC_wp_getRevisions::test_non_array_fields_returns_error
Failed asserting that Array () is an instance of class "IXR_Error".

/var/www/tests/phpunit/includes/abstract-testcase.php:909
/var/www/tests/phpunit/tests/xmlrpc/wp/getRevisions.php:92

ERRORS!
Tests: 348, Assertions: 1290, Errors: 8, Failures: 2.

[github-actions]

A commit was made that fixes the Trac ticket referenced in the description of this pull request.

SVN changeset: 63393
GitHub commit: 67c01d5

This PR will be closed, but please confirm the accuracy of this and reopen if there is more work to be done.