REST API: Update default values for fields in the block type schema

[gziolo]

Description

This change aligns with the state of the corresponding change proposed to WordPress core to WP_Block_Type class: https://core.trac.wordpress.org/ticket/48529.

More details about this optional field:
https://developer.wordpress.org/block-editor/developers/block-api/block-registration/#parent-optional

Related code that uses this field that confirms that using an empty array would lead to unexpected results:

gutenberg/packages/block-editor/src/store/selectors.js

Lines 1168 to 1173 in 1530b55

	const blockAllowedParentBlocks = blockType.parent;
	const parentName = getBlockName( state, rootClientId );
	const hasBlockAllowedParent = checkAllowList(
	blockAllowedParentBlocks,
	parentName
	);

gutenberg/packages/block-editor/src/store/selectors.js

Lines 1122 to 1136 in 1530b55

	const checkAllowList = ( list, item, defaultResult = null ) => {
	if ( isBoolean( list ) ) {
	return list;
	}
	if ( isArray( list ) ) {
	// TODO: when there is a canonical way to detect that we are editing a post
	// the following check should be changed to something like:
	// if ( includes( list, 'core/post-content' ) && getEditorMode() === 'post-content' && item === null )
	if ( includes( list, 'core/post-content' ) && item === null ) {
	return true;
	}
	return includes( list, item );
	}
	return defaultResult;
	};

[github-actions]

Size Change: 0 B

Total Size: 1.12 MB

ℹ️ View Unchanged

Filename	Size	Change
build/a11y/index.js	1.14 kB	0 B
build/annotations/index.js	3.62 kB	0 B
build/api-fetch/index.js	3.4 kB	0 B
build/autop/index.js	2.83 kB	0 B
build/blob/index.js	620 B	0 B
build/block-directory/index.js	6.48 kB	0 B
build/block-directory/style-rtl.css	787 B	0 B
build/block-directory/style.css	787 B	0 B
build/block-editor/index.js	106 kB	0 B
build/block-editor/style-rtl.css	11.3 kB	0 B
build/block-editor/style.css	11.3 kB	0 B
build/block-library/editor-rtl.css	7.87 kB	0 B
build/block-library/editor.css	7.88 kB	0 B
build/block-library/index.js	125 kB	0 B
build/block-library/style-rtl.css	7.68 kB	0 B
build/block-library/style.css	7.68 kB	0 B
build/block-library/theme-rtl.css	684 B	0 B
build/block-library/theme.css	686 B	0 B
build/block-serialization-default-parser/index.js	1.88 kB	0 B
build/block-serialization-spec-parser/index.js	3.1 kB	0 B
build/blocks/index.js	48.1 kB	0 B
build/components/index.js	190 kB	0 B
build/components/style-rtl.css	19.5 kB	0 B
build/components/style.css	19.5 kB	0 B
build/compose/index.js	9.32 kB	0 B
build/core-data/index.js	11.4 kB	0 B
build/data-controls/index.js	1.29 kB	0 B
build/data/index.js	8.43 kB	0 B
build/date/index.js	5.47 kB	0 B
build/deprecated/index.js	772 B	0 B
build/dom-ready/index.js	568 B	0 B
build/dom/index.js	3.11 kB	0 B
build/edit-navigation/index.js	7.88 kB	0 B
build/edit-navigation/style-rtl.css	857 B	0 B
build/edit-navigation/style.css	856 B	0 B
build/edit-post/index.js	302 kB	0 B
build/edit-post/style-rtl.css	5.43 kB	0 B
build/edit-post/style.css	5.43 kB	0 B
build/edit-site/index.js	14.1 kB	0 B
build/edit-site/style-rtl.css	2.96 kB	0 B
build/edit-site/style.css	2.96 kB	0 B
build/edit-widgets/index.js	8.88 kB	0 B
build/edit-widgets/style-rtl.css	2.4 kB	0 B
build/edit-widgets/style.css	2.4 kB	0 B
build/editor/editor-styles-rtl.css	425 B	0 B
build/editor/editor-styles.css	428 B	0 B
build/editor/index.js	44.6 kB	0 B
build/editor/style-rtl.css	4.26 kB	0 B
build/editor/style.css	4.27 kB	0 B
build/element/index.js	4.64 kB	0 B
build/escape-html/index.js	733 B	0 B
build/format-library/index.js	7.71 kB	0 B
build/format-library/style-rtl.css	502 B	0 B
build/format-library/style.css	502 B	0 B
build/hooks/index.js	2.13 kB	0 B
build/html-entities/index.js	622 B	0 B
build/i18n/index.js	3.56 kB	0 B
build/is-shallow-equal/index.js	711 B	0 B
build/keyboard-shortcuts/index.js	2.51 kB	0 B
build/keycodes/index.js	1.94 kB	0 B
build/list-reusable-blocks/index.js	3.12 kB	0 B
build/list-reusable-blocks/style-rtl.css	226 B	0 B
build/list-reusable-blocks/style.css	226 B	0 B
build/media-utils/index.js	5.29 kB	0 B
build/notices/index.js	1.79 kB	0 B
build/nux/index.js	3.4 kB	0 B
build/nux/style-rtl.css	616 B	0 B
build/nux/style.css	613 B	0 B
build/plugins/index.js	2.56 kB	0 B
build/primitives/index.js	1.5 kB	0 B
build/priority-queue/index.js	789 B	0 B
build/redux-routine/index.js	2.85 kB	0 B
build/rich-text/index.js	14.8 kB	0 B
build/server-side-render/index.js	2.68 kB	0 B
build/shortcode/index.js	1.7 kB	0 B
build/token-list/index.js	1.28 kB	0 B
build/url/index.js	4.02 kB	0 B
build/viewport/index.js	1.84 kB	0 B
build/warning/index.js	1.14 kB	0 B
build/wordcount/index.js	1.17 kB	0 B

_{compressed-size-action}

[spacedmonkey]

I will test this later today.

[gziolo]

As discussed in private chat, another option is to tweak the actual usage of this field in the inserter to treat an empty array as no parents and bail out from the check.

[aduth]

tweak the actual usage of this field in the inserter to treat an empty array as no parents and bail out from the check.

By "no parents", do you mean "no restriction on the types of parents" or "not allowed to be inserted within any nested context"? I think it could be a worthwhile distinction with each having valid use-cases, where it could be represented by the difference between [] and null.

[gziolo]

By "no parents", do you mean "no restriction on the types of parents" or "not allowed to be inserted within any nested context"? I think it could be a worthwhile distinction with each having valid use-cases, where it could be represented by the difference between [] and null.

Exactly, this is something I'm hesitant about. There is also an inserter flag in the supports property of the block definition that serves a similar purpose.

[aduth]

Related: #7845

[spacedmonkey]

This didn't work in my testing.

[spacedmonkey]

These lines need to change

} elseif ( isset( $schema['properties'][ $key ]['default'] ) ) {

} elseif ( array_key_exists( 'default', $schema['properties'][ $key ] ) ) {

The null value means you can't use isset.

[gziolo]

I went through the list of changes applied in WordPress core and tried to align this PR accordingly:
WordPress/wordpress-develop@822ca9e

• renamed text_domain to textdomain (seems to be preferred in WordPress core, https://github.com/WordPress/wordpress-develop/search?q=textdomain&unscoped_q=textdomain) and changed the default value to null to reflect the fact that it can be ommited
• removed all references to styleVariations to continue use styles that existed before
• updated the default value for attributes to null to make it work with the logic pointed by @aduth – we can change it later but I would prefer to keep it out of this ticket because it's very sensitive change
• updated parent to allow null value and make it the default - it makes it possible to distinguish between [] and null that can have different meanings as pointed in REST API: Update default values for fields in the block type schema #22695 (comment) by @aduth
• example is also sensible to null vs [] logic

It turned out example was missing in both RFC and REST API implementation.

[spacedmonkey]

This is line nit pick and this can be merged - https://github.com/WordPress/gutenberg/pull/22695/files#r433239396

[spacedmonkey]

LGTM