Babel macro: Add new Babel macro which handles block.json file transf…

…ormation

docs/manifest-devhub.json

@@ -1061,6 +1061,12 @@
 		"markdown_source": "../packages/autop/README.md",
 		"parent": "packages"
 	},
+	{
+		"title": "@wordpress/babel-block.macro",
+		"slug": "packages-babel-block.macro",
+		"markdown_source": "../packages/babel-block.macro/README.md",
+		"parent": "packages"
+	},
 	{
 		"title": "@wordpress/babel-plugin-import-jsx-pragma",
 		"slug": "packages-babel-plugin-import-jsx-pragma",

package.json

@@ -71,6 +71,7 @@
 		"@babel/runtime-corejs3": "7.4.4",
 		"@babel/traverse": "7.4.4",
 		"@octokit/rest": "16.26.0",
+		"@wordpress/babel-block.macro": "file:packages/babel-block.macro",
 		"@wordpress/babel-plugin-import-jsx-pragma": "file:packages/babel-plugin-import-jsx-pragma",
 		"@wordpress/babel-plugin-makepot": "file:packages/babel-plugin-makepot",
 		"@wordpress/babel-preset-default": "file:packages/babel-preset-default",
@@ -91,6 +92,7 @@
 		"babel-plugin-inline-json-import": "0.3.2",
 		"babel-plugin-react-native-classname-to-style": "1.2.2",
 		"babel-plugin-react-native-platform-specific-extensions": "1.1.1",
+		"babel-plugin-tester": "7.0.1",
 		"benchmark": "2.1.4",
 		"browserslist": "4.6.2",
 		"chalk": "2.4.1",

packages/babel-block.macro/.npmrc

@@ -0,0 +1 @@
+package-lock=false

packages/babel-block.macro/README.md

@@ -0,0 +1,13 @@
+# Babel Block Macro
+
+Babel block macro.
+
+## Installation
+
+Install the module to your project using [npm](https://www.npmjs.com/).
+
+```bash
+npm install @wordpress/babel-block.macro
+```
+
+<br/><br/><p align="center"><img src="https://s.w.org/style/images/codeispoetry.png?1" alt="Code is Poetry." /></p>

packages/babel-block.macro/macro.js

@@ -0,0 +1,79 @@
+/**
+ * External dependencies
+ */
+const { createMacro } = require( 'babel-plugin-macros' );
+const { existsSync, readFileSync } = require( 'fs' );
+const { mapKeys, pick } = require( 'lodash' );
+const { dirname, join, relative } = require( 'path' );
+
+function getFilename( [ filenamePath ], state ) {
+	const filename = filenamePath.evaluate().value;
+
+	return join(
+		relative( process.cwd(), dirname( state.file.opts.filename ) ),
+		filename
+	);
+}
+
+function readMetadata( filename ) {
+	if ( ! existsSync( filename ) ) {
+		throw new Error( `Invalid file name provided: ${ filename }.` );
+	}
+
+	const metadataRaw = readFileSync( filename, 'utf8' );
+
+	return JSON.parse( metadataRaw );
+}
+
+function formatMetadata( metadata, types ) {
+	const aliases = {
+		styleVariations: 'styles',
+	};
+	const replaceWithAlias = ( _, key ) => {
+		return aliases[ key ] || key;
+	};
+	const whitelistedProperties = [
+		'name',
+		'title',
+		'category',
+		'parent',
+		'icon',
+		'description',
+		'keywords',
+		'attributes',
+		'styles',
+	];
+
+	const metadataFiltered = pick(
+		mapKeys( metadata, replaceWithAlias ),
+		whitelistedProperties
+	);
+
+	const metadataNode = types.valueToNode( metadataFiltered );
+	/*const translatedProperties = [
+		'title',
+		'description',
+		'keywords',
+	];*/
+
+	return metadataNode;
+}
+
+function babelBlockMacro( { references, state, babel } ) {
+	const { types } = babel;
+	references.default.forEach( ( referencePath ) => {
+		if ( referencePath.parentPath.type === 'CallExpression' ) {
+			const metadata = readMetadata(
+				getFilename( referencePath.parentPath.get( 'arguments' ), state )
+			);
+
+			referencePath.parentPath.replaceWith( formatMetadata( metadata, types ) );
+		} else {
+			throw new Error(
+				`@wordpress/babel-block.macro can only be used as function call. You tried ${ referencePath.parentPath.type }.`,
+			);
+		}
+	} );
+}
+
+module.exports = createMacro( babelBlockMacro );

packages/babel-block.macro/package.json

@@ -0,0 +1,35 @@
+{
+	"name": "@wordpress/babel-block.macro",
+	"version": "1.0.0-alpha.1",
+	"description": "Babel block macro.",
+	"author": "The WordPress Contributors",
+	"license": "GPL-2.0-or-later",
+	"keywords": [
+		"wordpress",
+		"block",
+		"babel",
+		"macro"
+	],
+	"homepage": "https://github.com/WordPress/gutenberg/tree/master/packages/babel-block.macro/README.md",
+	"repository": {
+		"type": "git",
+		"url": "https://github.com/WordPress/gutenberg.git",
+		"directory": "packages/babel-block.macro"
+	},
+	"bugs": {
+		"url": "https://github.com/WordPress/gutenberg/issues"
+	},
+	"engines": {
+		"node": ">=10"
+	},
+	"files": [
+		"index.js"
+	],
+	"main": "index.js",
+	"dependencies": {
+		"babel-plugin-macros": "^2.6.1"
+	},
+	"publishConfig": {
+		"access": "public"
+	}
+}