Block Library: Add home link block

lib/blocks.php

@@ -26,6 +26,7 @@ function gutenberg_reregister_core_block_types() {
 				'group',
 				'heading',
 				'html',
+				'home-link',
 				'image',
 				'list',
 				'media-text',
@@ -59,6 +60,7 @@ function gutenberg_reregister_core_block_types() {
 				'loginout.php'                  => 'core/loginout',
 				'navigation.php'                => 'core/navigation',
 				'navigation-link.php'           => 'core/navigation-link',
+				'home-link.php'                 => 'core/home-link',
 				'rss.php'                       => 'core/rss',
 				'search.php'                    => 'core/search',
 				'shortcode.php'                 => 'core/shortcode',

packages/block-library/src/home-link/block.json

@@ -0,0 +1,29 @@
+{
+	"apiVersion": 2,
+	"name": "core/home-link",
+	"category": "design",
+	"parent": [ "core/navigation" ],
+	"title": "Home Link",
+	"description": "Create a link that always points to the homepage of the site. Usually not necessary if there is already a site title link present in the header.",
+	"textdomain": "default",
+	"attributes": {
+		"label": {
+			"type": "string"
+		}
+	},
+	"usesContext": [
+		"textColor",
+		"customTextColor",
+		"backgroundColor",
+		"customBackgroundColor",
+		"fontSize",
+		"customFontSize",
+		"style"
+	],
+	"supports": {
+		"reusable": false,
+		"html": false
+	},
+	"editorStyle": "wp-block-home-link-editor",
+	"style": "wp-block-home-link"
+}

packages/block-library/src/home-link/edit.js

@@ -0,0 +1,86 @@
+/**
+ * External dependencies
+ */
+import classnames from 'classnames';
+
+/**
+ * WordPress dependencies
+ */
+import { RichText, useBlockProps } from '@wordpress/block-editor';
+import { __ } from '@wordpress/i18n';
+import { useSelect } from '@wordpress/data';
+import { store as coreStore } from '@wordpress/core-data';
+import { useEffect } from '@wordpress/element';
+
+const preventDefault = ( event ) => event.preventDefault();
+
+export default function HomeEdit( {
+	attributes,
+	setAttributes,
+	context,
+	clientId,
+} ) {
+	const { homeUrl } = useSelect(
+		( select ) => {
+			const {
+				getUnstableBase, //site index
+			} = select( coreStore );
+			return {
+				homeUrl: getUnstableBase()?.home,
+			};
+		},
+		[ clientId ]
+	);
+
+	const { textColor, backgroundColor, style } = context;
+	const blockProps = useBlockProps( {
+		className: classnames( {
+			'has-text-color': !! textColor || !! style?.color?.text,
+			[ `has-${ textColor }-color` ]: !! textColor,
+			'has-background': !! backgroundColor || !! style?.color?.background,
+			[ `has-${ backgroundColor }-background-color` ]: !! backgroundColor,
+		} ),
+		style: {
+			color: style?.color?.text,
+			backgroundColor: style?.color?.background,
+		},
+	} );
+
+	const { label } = attributes;
+
+	useEffect( () => {
+		if ( label === undefined ) {
+			setAttributes( { label: __( 'Home' ) } );
+		}
+	}, [ clientId, label ] );
+
+	return (
+		<>
+			<li { ...blockProps }>
+				<a
+					className="wp-block-home-link__content"
+					href={ homeUrl }
+					onClick={ preventDefault }
+				>
+					<RichText
+						identifier="label"
+						className="wp-block-home-link__label"
+						value={ label }
+						onChange={ ( labelValue ) => {
+							setAttributes( { label: labelValue } );
+						} }
+						aria-label={ __( 'Home link text' ) }
+						placeholder={ __( 'Add home link' ) }
+						withoutInteractiveFormatting
+						allowedFormats={ [
+							'core/bold',
+							'core/italic',
+							'core/image',
+							'core/strikethrough',
+						] }
+					/>
+				</a>
+			</li>
+		</>
+	);
+}

packages/block-library/src/home-link/index.js

@@ -0,0 +1,30 @@
+/**
+ * WordPress dependencies
+ */
+import { _x } from '@wordpress/i18n';
+import { home } from '@wordpress/icons';
+
+/**
+ * Internal dependencies
+ */
+import metadata from './block.json';
+import edit from './edit';
+import save from './save';
+
+const { name } = metadata;
+
+export { metadata, name };
+
+export const settings = {
+	icon: home,
+
+	edit,
+
+	save,
+
+	example: {
+		attributes: {
+			label: _x( 'Home Link', 'block example' ),
+		},
+	},
+};

packages/block-library/src/home-link/index.php

@@ -0,0 +1,178 @@
+<?php
+/**
+ * Server-side rendering of the `core/home-link` block.
+ *
+ * @package gutenberg
+ */
+
+/**
+ * Build an array with CSS classes and inline styles defining the colors
+ * which will be applied to the home link markup in the front-end.
+ *
+ * @param  array $context home link block context.
+ * @return array Colors CSS classes and inline styles.
+ */
+function block_core_home_link_build_css_colors( $context ) {
+	$colors = array(
+		'css_classes'   => array(),
+		'inline_styles' => '',
+	);
+
+	// Text color.
+	$has_named_text_color  = array_key_exists( 'textColor', $context );
+	$has_custom_text_color = isset( $context['style']['color']['text'] );
+
+	// If has text color.
+	if ( $has_custom_text_color || $has_named_text_color ) {
+		// Add has-text-color class.
+		$colors['css_classes'][] = 'has-text-color';
+	}
+
+	if ( $has_named_text_color ) {
+		// Add the color class.
+		$colors['css_classes'][] = sprintf( 'has-%s-color', $context['textColor'] );
+	} elseif ( $has_custom_text_color ) {
+		// Add the custom color inline style.
+		$colors['inline_styles'] .= sprintf( 'color: %s;', $context['style']['color']['text'] );
+	}
+
+	// Background color.
+	$has_named_background_color  = array_key_exists( 'backgroundColor', $context );
+	$has_custom_background_color = isset( $context['style']['color']['background'] );
+
+	// If has background color.
+	if ( $has_custom_background_color || $has_named_background_color ) {
+		// Add has-background class.
+		$colors['css_classes'][] = 'has-background';
+	}
+
+	if ( $has_named_background_color ) {
+		// Add the background-color class.
+		$colors['css_classes'][] = sprintf( 'has-%s-background-color', $context['backgroundColor'] );
+	} elseif ( $has_custom_background_color ) {
+		// Add the custom background-color inline style.
+		$colors['inline_styles'] .= sprintf( 'background-color: %s;', $context['style']['color']['background'] );
+	}
+
+	return $colors;
+}
+
+/**
+ * Build an array with CSS classes and inline styles defining the font sizes
+ * which will be applied to the home link markup in the front-end.
+ *
+ * @param  array $context Home link block context.
+ * @return array Font size CSS classes and inline styles.
+ */
+function block_core_home_link_build_css_font_sizes( $context ) {
+	// CSS classes.
+	$font_sizes = array(
+		'css_classes'   => array(),
+		'inline_styles' => '',
+	);
+
+	$has_named_font_size  = array_key_exists( 'fontSize', $context );
+	$has_custom_font_size = isset( $context['style']['typography']['fontSize'] );
+
+	if ( $has_named_font_size ) {
+		// Add the font size class.
+		$font_sizes['css_classes'][] = sprintf( 'has-%s-font-size', $context['fontSize'] );
+	} elseif ( $has_custom_font_size ) {
+		// Add the custom font size inline style.
+		$font_sizes['inline_styles'] = sprintf( 'font-size: %spx;', $context['style']['typography']['fontSize'] );
+	}
+
+	return $font_sizes;
+}
+
+/**
+ * Builds an array with classes and style for the li wrapper
+ *
+ * @param  array $context    Home link block context.
+ * @return array The li wrapper attributes.
+ */
+function block_core_home_link_build_li_wrapper_attributes( $context ) {
+	$colors          = block_core_home_link_build_css_colors( $context );
+	$font_sizes      = block_core_home_link_build_css_font_sizes( $context );
+	$classes         = array_merge(
+		$colors['css_classes'],
+		$font_sizes['css_classes']
+	);
+	$style_attribute = ( $colors['inline_styles'] . $font_sizes['inline_styles'] );
+	$css_classes     = trim( implode( ' ', $classes ) );
+
+	$wrapper_attributes = get_block_wrapper_attributes(
+		array(
+			'class' => $css_classes,
+			'style' => $style_attribute,
+		)
+	);
+
+	return $wrapper_attributes;
+}
+
+/**
+ * Renders the `core/home-link` block.
+ *
+ * @param array $attributes The block attributes.
+ * @param array $content    The saved content.
+ * @param array $block      The parsed block.
+ *
+ * @return string Returns the post content with the home url added.
+ */
+function render_block_core_home_link( $attributes, $content, $block ) {
+	if ( empty( $attributes['label'] ) ) {
+		return '';
+	}
+
+	$wrapper_attributes = block_core_home_link_build_li_wrapper_attributes( $block->context );
+
+	$html = '<li ' . $wrapper_attributes . '><a class="wp-block-home-link__content"';
+
+	// Start appending HTML attributes to anchor tag.
+	$html .= ' href="' . esc_url( home_url() ) . '"';
+
+	// End appending HTML attributes to anchor tag.
+	$html .= '>';
+
+	if ( isset( $attributes['label'] ) ) {
+		$html .= wp_kses(
+			$attributes['label'],
+			array(
+				'code'   => array(),
+				'em'     => array(),
+				'img'    => array(
+					'scale' => array(),
+					'class' => array(),
+					'style' => array(),
+					'src'   => array(),
+					'alt'   => array(),
+				),
+				's'      => array(),
+				'span'   => array(
+					'style' => array(),
+				),
+				'strong' => array(),
+			)
+		);
+	}
+
+	$html .= '</a></li>';
+	return $html;
+}
+
+/**
+ * Register the home block
+ *
+ * @uses render_block_core_home_link()
+ * @throws WP_Error An WP_Error exception parsing the block definition.
+ */
+function register_block_core_home_link() {
+	register_block_type_from_metadata(
+		__DIR__ . '/home-link',
+		array(
+			'render_callback' => 'render_block_core_home_link',
+		)
+	);
+}
+add_action( 'init', 'register_block_core_home_link' );

packages/block-library/src/home-link/save.js

@@ -0,0 +1,8 @@
+/**
+ * WordPress dependencies
+ */
+import { InnerBlocks } from '@wordpress/block-editor';
+
+export default function save() {
+	return <InnerBlocks.Content />;
+}