From ad3135529ff7d589de1c25a4e2b39486c3272924 Mon Sep 17 00:00:00 2001
From: George Mamadashvili <georgemamadashvili@gmail.com>
Date: Mon, 22 Apr 2024 21:13:39 +0400
Subject: [PATCH] Blocks: Merge variations bootstrapped from a server with the
 client definitions (#60832)

Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>
Co-authored-by: jsnajdr <jsnajdr@git.wordpress.org>
Co-authored-by: tyxla <tyxla@git.wordpress.org>
Co-authored-by: t-hamano <wildworks@git.wordpress.org>
Co-authored-by: joemcgill <joemcgill@git.wordpress.org>
---
 packages/blocks/src/api/test/registration.js  | 45 +++++++++++++++++++
 .../blocks/src/store/process-block-type.js    | 40 ++++++++++++++++-
 2 files changed, 83 insertions(+), 2 deletions(-)

diff --git a/packages/blocks/src/api/test/registration.js b/packages/blocks/src/api/test/registration.js
index a97a456e0e22fa..f9a62346a72e41 100644
--- a/packages/blocks/src/api/test/registration.js
+++ b/packages/blocks/src/api/test/registration.js
@@ -398,6 +398,51 @@ describe( 'blocks', () => {
 			} );
 		} );
 
+		it( 'should merge settings provided by server and client', () => {
+			const blockName = 'core/test-block-with-merged-settings';
+			unstable__bootstrapServerSideBlockDefinitions( {
+				[ blockName ]: {
+					variations: [
+						{ name: 'foo', label: 'Foo' },
+						{ name: 'baz', label: 'Baz', description: 'Testing' },
+					],
+				},
+			} );
+
+			const blockType = {
+				title: 'block settings merge',
+				variations: [
+					{ name: 'bar', label: 'Bar' },
+					{ name: 'baz', label: 'Baz', icon: 'layout' },
+				],
+			};
+			registerBlockType( blockName, blockType );
+			expect( getBlockType( blockName ) ).toEqual( {
+				name: blockName,
+				save: expect.any( Function ),
+				title: 'block settings merge',
+				icon: { src: BLOCK_ICON_DEFAULT },
+				attributes: {},
+				providesContext: {},
+				usesContext: [],
+				keywords: [],
+				selectors: {},
+				supports: {},
+				styles: [],
+				variations: [
+					{ name: 'foo', label: 'Foo' },
+					{
+						description: 'Testing',
+						name: 'baz',
+						label: 'Baz',
+						icon: 'layout',
+					},
+					{ name: 'bar', label: 'Bar' },
+				],
+				blockHooks: {},
+			} );
+		} );
+
 		// This test can be removed once the polyfill for blockHooks gets removed.
 		it( 'should polyfill blockHooks using metadata on the client when not set on the server', () => {
 			const blockName = 'tests/hooked-block';
diff --git a/packages/blocks/src/store/process-block-type.js b/packages/blocks/src/store/process-block-type.js
index 889f59b55e392e..154f74c6ab7296 100644
--- a/packages/blocks/src/store/process-block-type.js
+++ b/packages/blocks/src/store/process-block-type.js
@@ -33,6 +33,37 @@ const LEGACY_CATEGORY_MAPPING = {
 	layout: 'design',
 };
 
+/**
+ * Merge block variations bootstrapped from the server and client.
+ *
+ * When a variation is registered in both places, its properties are merged.
+ *
+ * @param {Array} bootstrappedVariations - A block type variations from the server.
+ * @param {Array} clientVariations       - A block type variations from the client.
+ * @return {Array} The merged array of block variations.
+ */
+function mergeBlockVariations(
+	bootstrappedVariations = [],
+	clientVariations = []
+) {
+	const result = [ ...bootstrappedVariations ];
+
+	clientVariations.forEach( ( clientVariation ) => {
+		const index = result.findIndex(
+			( bootstrappedVariation ) =>
+				bootstrappedVariation.name === clientVariation.name
+		);
+
+		if ( index !== -1 ) {
+			result[ index ] = { ...result[ index ], ...clientVariation };
+		} else {
+			result.push( clientVariation );
+		}
+	} );
+
+	return result;
+}
+
 /**
  * Takes the unprocessed block type settings, merges them with block type metadata
  * and applies all the existing filters for the registered block type.
@@ -46,6 +77,8 @@ const LEGACY_CATEGORY_MAPPING = {
 export const processBlockType =
 	( name, blockSettings ) =>
 	( { select } ) => {
+		const bootstrappedBlockType = select.getBootstrappedBlockType( name );
+
 		const blockType = {
 			name,
 			icon: BLOCK_ICON_DEFAULT,
@@ -56,11 +89,14 @@ export const processBlockType =
 			selectors: {},
 			supports: {},
 			styles: [],
-			variations: [],
 			blockHooks: {},
 			save: () => null,
-			...select.getBootstrappedBlockType( name ),
+			...bootstrappedBlockType,
 			...blockSettings,
+			variations: mergeBlockVariations(
+				bootstrappedBlockType?.variations,
+				blockSettings?.variations
+			),
 		};
 
 		const settings = applyFilters(