Scan block.json to generate a list of files to be copied via CopyWebpackPlugin

packages/scripts/CHANGELOG.md

@@ -1,7 +1,7 @@
 <!-- Learn how to maintain this file at https://github.com/WordPress/gutenberg/tree/HEAD/packages#maintaining-changelogs. -->
 
 ## Unreleased
-
+-   Parse block.json files to look for a `files` property and generate a list of files to be copied from `src` to the output directory (`build` by default)([39653](https://github.com/WordPress/gutenberg/pull/39653)
 ## 22.2.0 (2022-03-11)
 
 ### Enhancement

packages/scripts/config/webpack.config.js

@@ -26,6 +26,7 @@ const {
 	hasCssnanoConfig,
 	hasPostCSSConfig,
 	getWebpackEntryPoints,
+	getFilesToCopy,
 } = require( '../utils' );
 
 const isProduction = process.env.NODE_ENV === 'production';
@@ -36,9 +37,7 @@ if ( ! browserslist.findConfig( '.' ) ) {
 }
 const hasReactFastRefresh = hasArgInCLI( '--hot' ) && ! isProduction;
 
-const copyWebPackPattens = process.env.WP_COPY_PHP_FILES_TO_DIST
-	? '**/{block.json,*.php}'
-	: '**/block.json';
+const copyWebPackPattens = getFilesToCopy();
 
 const cssLoaders = [
 	{

packages/scripts/utils/config.js

@@ -284,7 +284,46 @@ function getWebpackEntryPoints() {
 	};
 }
 
+/**
+ * Generates a list of files to be copied from the src directory to the build directory based on a "files"
+ * property in block.json
+ *
+ * @return {string} The copy pattern passed to the CopyWebpackPlugin
+ */
+function getFilesToCopy() {
+	// Continue only if the `src` directory exists.
+	if ( ! hasProjectFile( 'src' ) ) {
+		return {};
+	}
+
+	// 2. Checks whether any block metadata files can be detected in the `src` directory.
+	//    It scans all discovered files looking for JavaScript assets and converts them to entry points.
+	const blockMetadataFiles = glob( 'src/**/block.json', {
+		absolute: true,
+	} );
+
+	const filesArray = process.env.WP_COPY_PHP_FILES_TO_DIST
+		? [ 'block.json', '*.php' ]
+		: [ 'block.json' ];
+
+	if ( blockMetadataFiles.length > 0 ) {
+		const fileList = blockMetadataFiles.reduce(
+			( array, blockMetadataFile ) => {
+				const { files } = require( blockMetadataFile );
+				return files ? [ ...array, ...files.split( ',' ) ] : array;
+			},
+			filesArray
+		);
+
+		// Create the pattern to be used.
+		return `**/{${ fileList.join( ',' ) }}`;
+	}
+	// Return the default pattern
+	return `**/{${ filesArray.join( ',' ) }}`;
+}
+
 module.exports = {
+	getFilesToCopy,
 	getJestOverrideConfigFile,
 	getWebpackArgs,
 	getWebpackEntryPoints,

packages/scripts/utils/index.js

@@ -11,6 +11,7 @@ const {
 	spawnScript,
 } = require( './cli' );
 const {
+	getFilesToCopy,
 	getJestOverrideConfigFile,
 	getWebpackArgs,
 	getWebpackEntryPoints,
@@ -29,6 +30,7 @@ module.exports = {
 	getArgFromCLI,
 	getArgsFromCLI,
 	getFileArgsFromCLI,
+	getFilesToCopy,
 	getJestOverrideConfigFile,
 	getNodeArgsFromCLI,
 	getPackageProp,