MDL-66307 js: Add missing plugintypes structure in subplugin read
[moodle.git] / babel-plugin-add-module-to-define.js
CommitLineData
c53f86d4
RW
1// This file is part of Moodle - http://moodle.org/
2//
3// Moodle is free software: you can redistribute it and/or modify
4// it under the terms of the GNU General Public License as published by
5// the Free Software Foundation, either version 3 of the License, or
6// (at your option) any later version.
7//
8// Moodle is distributed in the hope that it will be useful,
9// but WITHOUT ANY WARRANTY; without even the implied warranty of
10// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11// GNU General Public License for more details.
12//
13// You should have received a copy of the GNU General Public License
14// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
15
16/**
17 * This is a babel plugin to add the Moodle module names to the AMD modules
18 * as part of the transpiling process.
19 *
20 * In addition it will also add a return statement for the default export if the
21 * module is using default exports. This is a highly specific Moodle thing because
22 * we're transpiling to AMD and none of the existing Babel 7 plugins work correctly.
23 *
24 * This will fix the issue where an ES6 module using "export default Foo" will be
25 * transpiled into an AMD module that returns {default: Foo}; Instead it will now
26 * just simply return Foo.
27 *
28 * Note: This means all other named exports in that module are ignored and won't be
29 * exported.
30 *
31 * @copyright 2018 Ryan Wyllie <ryan@moodle.com>
32 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
33 */
34
35"use strict";
36
37module.exports = ({ template, types }) => {
38 const fs = require('fs');
39 const glob = require('glob');
40 const cwd = process.cwd();
41
42 // Static variable to hold the modules.
43 let moodleSubsystems = null;
44 let moodlePlugins = null;
45
46 /**
47 * Parse Moodle's JSON files containing the lists of components.
48 *
49 * The values are stored in the static variables because we
50 * only need to load them once per transpiling run.
51 */
52 function loadMoodleModules() {
53 moodleSubsystems = {'lib': 'core'};
54 moodlePlugins = {};
55 let components = fs.readFileSync('lib/components.json');
56 components = JSON.parse(components);
57
58 for (const [component, path] of Object.entries(components.subsystems)) {
59 if (path) {
60 // Prefix "core_" to the front of the subsystems.
61 moodleSubsystems[path] = `core_${component}`;
62 }
63 }
64
65 for (const [component, path] of Object.entries(components.plugintypes)) {
66 if (path) {
67 moodlePlugins[path] = component;
68 }
69 }
70
71 for (const file of glob.sync('**/db/subplugins.json')) {
72 var rawContents = fs.readFileSync(file);
73 var subplugins = JSON.parse(rawContents);
74
2c28ba88 75 for (const [component, path] of Object.entries(subplugins.plugintypes)) {
c53f86d4
RW
76 if (path) {
77 moodlePlugins[path] = component;
78 }
79 }
80 }
81 }
82
83 /**
84 * Search the list of components that match the given file name
85 * and return the Moodle component for that file, if found.
86 *
87 * Throw an exception if no matching component is found.
88 *
89 * @throws {Error}
90 * @param {string} searchFileName The file name to look for.
91 * @return {string} Moodle component
92 */
93 function getModuleNameFromFileName(searchFileName) {
94 searchFileName = fs.realpathSync(searchFileName);
95 const relativeFileName = searchFileName.replace(`${cwd}/`, '');
96 const [componentPath, file] = relativeFileName.split('/amd/src/');
97 const fileName = file.replace('.js', '');
98
99 // Check subsystems first which require an exact match.
100 if (moodleSubsystems.hasOwnProperty(componentPath)) {
101 return `${moodleSubsystems[componentPath]}/${fileName}`;
102 }
103
104 // It's not a subsystem so it must be a plugin. Moodle defines root folders
105 // where plugins can be installed so our path with be <plugin_root>/<plugin_name>.
106 // Let's separate the two.
107 let pathParts = componentPath.split('/');
108 const pluginName = pathParts.pop();
109 const pluginPath = pathParts.join('/');
110
111 // The plugin path mutch match exactly because some plugins are subplugins of
112 // other plugins which means their paths would partially match.
113 if (moodlePlugins.hasOwnProperty(pluginPath)) {
114 return `${moodlePlugins[pluginPath]}_${pluginName}/${fileName}`;
115 }
116
117 // This matches the previous PHP behaviour that would throw an exception
118 // if it couldn't parse an AMD file.
119 throw new Error('Unable to find module name for ' + searchFileName);
120 }
121
122 // This is heavily inspired by the babel-plugin-add-module-exports plugin.
123 // See: https://github.com/59naga/babel-plugin-add-module-exports
124 //
125 // This is used when we detect a module using "export default Foo;" to make
126 // sure the transpiled code just returns Foo directly rather than an object
127 // with the default property (i.e. {default: Foo}).
128 //
129 // Note: This means that we can't support modules that combine named exports
130 // with a default export.
131 function addModuleExportsDefaults(path, exportObjectName) {
132 const rootPath = path.findParent(path => {
133 return path.key === 'body' || !path.parentPath;
134 });
135
136 // HACK: `path.node.body.push` instead of path.pushContainer(due doesn't work in Plugin.post).
137 // This is hardcoded to work specifically with AMD.
138 rootPath.node.body.push(template(`return ${exportObjectName}.default`)())
139 }
140
141 return {
142 pre() {
143 this.seenDefine = false;
144 this.addedReturnForDefaultExport = false;
145
146 if (moodleSubsystems === null) {
147 loadMoodleModules();
148 }
149 },
150 visitor: {
151 // Plugin ordering is only respected if we visit the "Program" node.
152 // See: https://babeljs.io/docs/en/plugins.html#plugin-preset-ordering
153 //
154 // We require this to run after the other AMD module transformation so
155 // let's visit the "Program" node.
156 Program: {
157 exit(path) {
158 path.traverse({
159 CallExpression(path) {
160 // If we find a "define" function call.
161 if (!this.seenDefine && path.get('callee').isIdentifier({name: 'define'})) {
162 // We only want to modify the first instance of define that we find.
163 this.seenDefine = true;
164 // Get the Moodle component for the file being processed.
165 var moduleName = getModuleNameFromFileName(this.file.opts.filename);
166 // Add the module name as the first argument to the define function.
167 path.node.arguments.unshift(types.stringLiteral(moduleName));
168 // Add a space after the define function in the built file so that previous versions
169 // of Moodle will not try to add the module name to the file when it's being served
170 // by PHP. This forces the regex in PHP to not match for this file.
171 path.node.callee.name = 'define ';
172 }
173
174 // Check for any Object.defineProperty('exports', 'default') calls.
175 if (!this.addedReturnForDefaultExport && path.get('callee').matchesPattern('Object.defineProperty')) {
176 const [identifier, prop] = path.get('arguments')
177 const objectName = identifier.get('name').node
178 const propertyName = prop.get('value').node
179
180 if ((objectName === 'exports' || objectName === '_exports') && propertyName === 'default') {
181 addModuleExportsDefaults(path, objectName);
182 this.addedReturnForDefaultExport = true;
183 }
184 }
185 },
186 AssignmentExpression(path) {
187 // Check for an exports.default assignments.
188 if (
189 !this.addedReturnForDefaultExport &&
190 (
191 path.get('left').matchesPattern('exports.default') ||
192 path.get('left').matchesPattern('_exports.default')
193 )
194 ) {
195 const objectName = path.get('left.object.name').node;
196 addModuleExportsDefaults(path, objectName);
197 this.addedReturnForDefaultExport = true;
198 }
199 }
200 }, this);
201 }
202 }
203 }
204 };
2c28ba88 205};