[wp-trac] [WordPress Trac] #61910: register_block_type_from_metadata fails to register style attribute when using $args

[WordPress Trac]

#61910: register_block_type_from_metadata fails to register style attribute when
using $args
--------------------------+-----------------------------
 Reporter:  mreishus      |      Owner:  (none)
     Type:  defect (bug)  |     Status:  new
 Priority:  normal        |  Milestone:  Awaiting Review
Component:  General       |    Version:
 Severity:  normal        |   Keywords:
  Focuses:                |
--------------------------+-----------------------------
 = Summary =

 The `register_block_type_from_metadata` function fails to properly
 register a block's `style` attribute when the block is registered using
 the `$args` parameter instead of reading from a `block.json` file.

 = Steps to Reproduce =

 1. Call `register_block_type_from_metadata` and pass the block
 configuration in the `$args` array instead of reading from `block.json`.
 The first argument should be an empty string to specify a `block.json`
 file is not used.
 2. Include a `style` attribute in `$args` specifying an array of style
 handles.
 3. Observe a PHP warning about an undefined index 'name' when it attempts
 to call `register_block_style_handle`.

 = Expected Result =

 The block should register successfully with the specified `style`
 attribute. No PHP warnings should be generated.

 = Actual Result =

 A PHP warning is emitted:
 {{{
 Warning: Undefined array key "name" in .../wp-includes/blocks.php on line
 294
 }}}

 The `style` attribute is not properly registered for the block.

 = Relevant Code =

 The issue lies in this part of `register_block_type_from_metadata`:

 {{{#!php
 foreach ( $style_fields as $metadata_field_name => $settings_field_name )
 {
     if ( ! empty( $settings[ $metadata_field_name ] ) ) {
         $metadata[ $metadata_field_name ] = $settings[
 $metadata_field_name ];
     }
     if ( ! empty( $metadata[ $metadata_field_name ] ) ) {
         $styles           = $metadata[ $metadata_field_name ];
         $processed_styles = array();
         if ( is_array( $styles ) ) {
             for ( $index = 0; $index < count( $styles ); $index++ ) {
                 $result = register_block_style_handle(
                     $metadata,
                     $metadata_field_name,
                     $index
                 );
                 if ( $result ) {
                     $processed_styles[] = $result;
                 }
             }
         } else {
             $result = register_block_style_handle(
                 $metadata,
                 $metadata_field_name
             );
             if ( $result ) {
                 $processed_styles[] = $result;
             }
         }
         $settings[ $settings_field_name ] = $processed_styles;
     }
 }
 }}}

 When calling `register_block_style_handle`, it passes the `$metadata`
 array. However, when registering via `$args`, the block `name` is not
 present in `$metadata`. It only exists in `$args`/`$settings` at this
 point.


 = Unit Test =

 Here is a failing unit test that demonstrates the issue: (see attached)

 The test currently fails due to the PHP warning.

 = Related =

 #56865, [57026] - Original change allowing
 `register_block_type_from_metadata()` to be used without a block.json
 file.

-- 
Ticket URL: <https://core.trac.wordpress.org/ticket/61910>
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