Feature : Recursive allowedBlocks rule in InnerBlocks

[Vrishabhsk]

What?

• Closes Option to make AllowedBlocks setting recursive #72803
• Restricts the allowedBlocks for blocks that are used in InnerBlocks without explicitly mentioning them for each block.

Why?

• Reduces effort to define allowedBlocks for each nested block in an InnerBlock by inheriting parent's rule.
• Allows wider restriction on block usage with minimal effort.

How?

• New boolean attribute for InnerBlocks : inheritAllowedBlocks
• When added as true, the canInsertBlockTypeUnmemoized function checks if the block is to be allowed or not.
• The function calls the new getInheritedAllowedBlocks function internally to verify the parent-child relation.
• The block is then visible / hidden based on that.

Testing Instructions

1. Create a block that uses InnerBlock
2. Set the allowedBlocks to the following

const ALLOWED_BLOCKS = [
	'core/heading',
	'core/group'
];

<InnerBlocks
	allowedBlocks={ ALLOWED_BLOCKS }
	template={ [
		[ 'core/paragraph', {
			placeholder: __( 'Add content here. Only allowed blocks can be inserted...', 'inherit-allowed-blocks-demo' )
		} ],
	] }
	renderAppender={ InnerBlocks.ButtonBlockAppender }
/>

3. Use the block in the editor, and add a Group block, select the orientation, then you can add Paragraph element
4. Modify the InnerBlocks as follows:

<InnerBlocks
	allowedBlocks={ ALLOWED_BLOCKS }
	template={ [
		[ 'core/paragraph', {
			placeholder: __( 'Add content here. Only allowed blocks can be inserted...', 'inherit-allowed-blocks-demo' )
		} ],
	] }
        inheritAllowedBlocks={ true }
	renderAppender={ InnerBlocks.ButtonBlockAppender }
/>

5. Follow the step 3 again and now you won't be able to add Paragraph element within the Group block.

[github-actions]

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Co-authored-by: Vrishabhsk <vrishabhsk@git.wordpress.org>
Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>
Co-authored-by: eric-michel <ytfeldrawkcab@git.wordpress.org>

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[Mamaduka]

Thanks for contributing, @Vrishabhsk!

Is there a corresponding issue on this repo for this request? I would also recommend avoiding linking private issues here.

[Vrishabhsk]

Oh my bad @Mamaduka. Completely overlooked by me.

Here's the original issue : #72803