require 'execjs' require 'mini_racer' module Tilt class ES6ModuleTranspilerTemplate < Tilt::Template self.default_mime_type = 'application/javascript' @mutex = Mutex.new @ctx_init = Mutex.new def self.call(input) filename = input[:filename] source = input[:data] context = input[:environment].context_class.new(input) result = new(filename) { source }.render(context) context.metadata.merge(data: result) end def prepare # intentionally left empty # Tilt requires this method to be defined end def self.create_new_context # timeout any eval that takes longer than 15 seconds ctx = MiniRacer::Context.new(timeout: 15000) ctx.eval("var self = this; #{File.read("#{Rails.root}/vendor/assets/javascripts/babel.js")}") ctx.eval(File.read(Ember::Source.bundled_path_for('ember-template-compiler.js'))) ctx.eval("module = {}; exports = {};") ctx.attach("rails.logger.info", proc { |err| Rails.logger.info(err.to_s) }) ctx.attach("rails.logger.error", proc { |err| Rails.logger.error(err.to_s) }) ctx.eval <<JS console = { prefix: "", log: function(msg){ rails.logger.info(console.prefix + msg); }, error: function(msg){ rails.logger.error(console.prefix + msg); } } JS source = File.read("#{Rails.root}/lib/javascripts/widget-hbs-compiler.js.es6") js_source = ::JSON.generate(source, quirks_mode: true) js = ctx.eval("Babel.transform(#{js_source}, { ast: false, plugins: ['check-es2015-constants', 'transform-es2015-arrow-functions', 'transform-es2015-block-scoped-functions', 'transform-es2015-block-scoping', 'transform-es2015-classes', 'transform-es2015-computed-properties', 'transform-es2015-destructuring', 'transform-es2015-duplicate-keys', 'transform-es2015-for-of', 'transform-es2015-function-name', 'transform-es2015-literals', 'transform-es2015-object-super', 'transform-es2015-parameters', 'transform-es2015-shorthand-properties', 'transform-es2015-spread', 'transform-es2015-sticky-regex', 'transform-es2015-template-literals', 'transform-es2015-typeof-symbol', 'transform-es2015-unicode-regex'] }).code") ctx.eval(js) ctx end def self.reset_context @ctx&.dispose @ctx = nil end def self.v8 return @ctx if @ctx # ensure we only init one of these @ctx_init.synchronize do return @ctx if @ctx @ctx = create_new_context end @ctx end class JavaScriptError < StandardError attr_accessor :message, :backtrace def initialize(message, backtrace) @message = message @backtrace = backtrace end end def self.protect @mutex.synchronize do yield end end def whitelisted?(path) @@whitelisted ||= Set.new( ["discourse/models/nav-item", "discourse/models/user-action", "discourse/routes/discourse", "discourse/models/category", "discourse/models/trust-level", "discourse/models/site", "discourse/models/user", "discourse/models/session", "discourse/models/model", "discourse/models/topic", "discourse/models/post", "discourse/views/grouped"] ) @@whitelisted.include?(path) || path =~ /discourse\/mixins/ end def babel_transpile(source) klass = self.class klass.protect do klass.v8.eval("console.prefix = 'BABEL: babel-eval: ';") @output = klass.v8.eval(babel_source(source)) end end def module_transpile(source, root_path, logical_path) klass = self.class klass.protect do klass.v8.eval("console.prefix = 'BABEL: babel-eval: ';") transpiled = babel_source( source, module_name: module_name(root_path, logical_path), filename: logical_path ) @output = klass.v8.eval(transpiled) end end def evaluate(scope, locals, &block) return @output if @output klass = self.class klass.protect do klass.v8.eval("console.prefix = 'BABEL: #{scope.logical_path}: ';") source = babel_source( data, module_name: module_name(scope.root_path, scope.logical_path), filename: scope.logical_path ) @output = klass.v8.eval(source) end # For backwards compatibility with plugins, for now export the Global format too. # We should eventually have an upgrade system for plugins to use ES6 or some other # resolve based API. if whitelisted?(scope.logical_path) && scope.logical_path =~ /(discourse|admin)\/(controllers|components|views|routes|mixins|models)\/(.*)/ type = Regexp.last_match[2] file_name = Regexp.last_match[3].gsub(/[\-\/]/, '_') class_name = file_name.classify # Rails removes pluralization when calling classify if file_name.end_with?('s') && (!class_name.end_with?('s')) class_name << "s" end require_name = module_name(scope.root_path, scope.logical_path) if require_name !~ /\-test$/ && require_name !~ /^discourse\/plugins\// result = "#{class_name}#{type.classify}" # HAX result = "Controller" if result == "ControllerController" result = "Route" if result == "DiscourseRoute" result = "View" if result == "ViewView" result.gsub!(/Mixin$/, '') result.gsub!(/Model$/, '') if result != "PostMenuView" @output << "\n\nDiscourse.#{result} = require('#{require_name}').default;\n" end end end @output end def babel_source(source, opts = nil) opts ||= {} js_source = ::JSON.generate(source, quirks_mode: true) if opts[:module_name] && transpile_into_module? filename = opts[:filename] || 'unknown' "Babel.transform(#{js_source}, { moduleId: '#{opts[:module_name]}', filename: '#{filename}', ast: false, presets: ['es2015'], plugins: [['transform-es2015-modules-amd', {noInterop: true}], 'transform-decorators-legacy', exports.WidgetHbsCompiler] }).code" else "Babel.transform(#{js_source}, { ast: false, plugins: ['check-es2015-constants', 'transform-es2015-arrow-functions', 'transform-es2015-block-scoped-functions', 'transform-es2015-block-scoping', 'transform-es2015-classes', 'transform-es2015-computed-properties', 'transform-es2015-destructuring', 'transform-es2015-duplicate-keys', 'transform-es2015-for-of', 'transform-es2015-function-name', 'transform-es2015-literals', 'transform-es2015-object-super', 'transform-es2015-parameters', 'transform-es2015-shorthand-properties', 'transform-es2015-spread', 'transform-es2015-sticky-regex', 'transform-es2015-template-literals', 'transform-es2015-typeof-symbol', 'transform-es2015-unicode-regex', 'transform-regenerator', 'transform-decorators-legacy', exports.WidgetHbsCompiler] }).code" end end private def transpile_into_module? file.nil? || file.exclude?('.no-module') end def module_name(root_path, logical_path) path = nil root_base = File.basename(Rails.root) # If the resource is a plugin, use the plugin name as a prefix if root_path =~ /(.*\/#{root_base}\/plugins\/[^\/]+)\// plugin_path = "#{Regexp.last_match[1]}/plugin.rb" plugin = Discourse.plugins.find { |p| p.path == plugin_path } path = "discourse/plugins/#{plugin.name}/#{logical_path.sub(/javascripts\//, '')}" if plugin end path ||= logical_path if ES6ModuleTranspiler.transform path = ES6ModuleTranspiler.transform.call(path) end path end def compiler_method type = { amd: 'AMD', cjs: 'CJS', globals: 'Globals' }[ES6ModuleTranspiler.compile_to.to_sym] "to#{type}" end def compiler_options ::JSON.generate(ES6ModuleTranspiler.compiler_options, quirks_mode: true) end end end