Add Block Transform to transform Embed blocks into Paragraph blocks.

packages/block-library/src/embed/core-embeds.js

@@ -151,15 +151,17 @@ export const others = [
 			title: 'Crowdsignal',
 			icon: embedContentIcon,
 			keywords: [ 'polldaddy' ],
-			transform: [ {
-				type: 'block',
-				blocks: [ 'core-embed/polldaddy' ],
-				transform: ( content ) => {
-					return createBlock( 'core-embed/crowdsignal', {
-						content,
-					} );
-				},
-			} ],
+			transforms: {
+				from: [ {
+					type: 'block',
+					blocks: [ 'core-embed/polldaddy' ],
+					transform: ( content ) => {
+						return createBlock( 'core-embed/crowdsignal', {
+							content,
+						} );
+					},
+				} ],
+			},
 			description: __( 'Embed Crowdsignal (formerly Polldaddy) content.' ),
 		},
 		patterns: [ /^https?:\/\/((.+\.)?polldaddy\.com|poll\.fm|.+\.survey\.fm)\/.+/i ],
@@ -312,15 +314,17 @@ export const others = [
 		settings: {
 			title: 'Speaker Deck',
 			icon: embedContentIcon,
-			transform: [ {
-				type: 'block',
-				blocks: [ 'core-embed/speaker' ],
-				transform: ( content ) => {
-					return createBlock( 'core-embed/speaker-deck', {
-						content,
-					} );
-				},
-			} ],
+			transforms: {
+				from: [ {
+					type: 'block',
+					blocks: [ 'core-embed/speaker' ],
+					transform: ( content ) => {
+						return createBlock( 'core-embed/speaker-deck', {
+							content,
+						} );
+					},
+				} ],
+			},
 			description: __( 'Embed Speaker Deck content.' ),
 		},
 		patterns: [ /^https?:\/\/(www\.)?speakerdeck\.com\/.+/i ],

packages/block-library/src/embed/index.js

@@ -1,15 +1,20 @@
+/**
+ * External dependencies
+ */
+import { concat, get } from 'lodash';
+
 /**
  * Internal dependencies
  */
 import { common as commonEmbeds, others as otherEmbeds } from './core-embeds';
 import { embedContentIcon } from './icons';
 import { getEmbedBlockSettings } from './settings';
+import transforms from './transforms';
 
 /**
  * WordPress dependencies
  */
 import { __, _x } from '@wordpress/i18n';
-import { createBlock } from '@wordpress/blocks';
 
 export const name = 'core/embed';
 
@@ -19,35 +24,37 @@ export const settings = getEmbedBlockSettings( {
 	icon: embedContentIcon,
 	// Unknown embeds should not be responsive by default.
 	responsive: false,
-	transforms: {
-		from: [
-			{
-				type: 'raw',
-				isMatch: ( node ) => node.nodeName === 'P' && /^\s*(https?:\/\/\S+)\s*$/i.test( node.textContent ),
-				transform: ( node ) => {
-					return createBlock( 'core/embed', {
-						url: node.textContent.trim(),
-					} );
-				},
-			},
-		],
-	},
+	transforms,
 } );
 
 export const common = commonEmbeds.map(
 	( embedDefinition ) => {
+		const embedSettings = getEmbedBlockSettings( embedDefinition.settings );
 		return {
 			...embedDefinition,
-			settings: getEmbedBlockSettings( embedDefinition.settings ),
+			settings: {
+				...embedSettings,
+				transforms: {
+					from: concat( get( transforms, 'from', [] ), get( embedSettings, 'transforms.from', [] ) ).filter( Boolean ),
+					to: concat( get( transforms, 'to', [] ), get( embedSettings, 'transforms.to', [] ) ).filter( Boolean ),
+				},
+			},
 		};
 	}
 );
 
 export const others = otherEmbeds.map(
 	( embedDefinition ) => {
+		const embedSettings = getEmbedBlockSettings( embedDefinition.settings );
 		return {
 			...embedDefinition,
-			settings: getEmbedBlockSettings( embedDefinition.settings ),
+			settings: {
+				...embedSettings,
+				transforms: {
+					from: concat( get( transforms, 'from', [] ), get( embedSettings, 'transforms.from', [] ) ).filter( Boolean ),
+					to: concat( get( transforms, 'to', [] ), get( embedSettings, 'transforms.to', [] ) ).filter( Boolean ),
+				},
+			},
 		};
 	}
 );

packages/block-library/src/embed/transforms.js

@@ -0,0 +1,33 @@
+/**
+ * WordPress dependencies
+ */
+import { renderToString } from '@wordpress/element';
+import { createBlock } from '@wordpress/blocks';
+
+const transforms = {
+	from: [
+		{
+			type: 'raw',
+			isMatch: ( node ) => node.nodeName === 'P' && /^\s*(https?:\/\/\S+)\s*$/i.test( node.textContent ),
+			transform: ( node ) => {
+				return createBlock( 'core/embed', {
+					url: node.textContent.trim(),
+				} );
+			},
+		},
+	],
+	to: [
+		{
+			type: 'block',
+			blocks: [ 'core/paragraph' ],
+			transform: ( { url, caption } ) => {
+				const link = <a href={ url }>{ caption || url }</a>;
+				return createBlock( 'core/paragraph', {
+					content: renderToString( link ),
+				} );
+			},
+		},
+	],
+};
+
+export default transforms;