Add support for requirejs 'module' module. (#26)

#25

src/amd.spec.ts

@@ -31,3 +31,11 @@ test('getHostedModuleUrl', () => {
       .pathname
   ).toBe('/npm/@jupyter-widgets/[email protected]/css/index.css');
 });
+
+test('requirejs magic modules', async () => {
+  const loader = new Loader();
+  loader.define('foo', ['module'], (module) => {
+    return `module: ${module.id}`;
+  });
+  expect(await loader.load('foo')).toBe('module: foo');
+});

src/amd.ts

@@ -91,6 +91,14 @@ export class Loader {
         const requirements = await Promise.all(
           module.dependencies.map((dependency) => {
             const definition = this.definitions.get(dependency);
+            // Support requirejs magic modules:
+            // https://github.com/requirejs/requirejs/wiki/Differences-between-the-simplified-CommonJS-wrapper-and-standard-AMD-define#magic
+            if (dependency === 'module') {
+              return {
+                id: module.id,
+                url: this.resolveModule(module.id),
+              };
+            }
             if (!definition) {
               throw new Error(`Unknown dependency ${dependency}`);
             }
@@ -121,6 +129,7 @@ export class Loader {
     const module = {
       factory: factory as () => unknown,
       dependencies,
+      id: moduleId,
     };
     if (!definition) {
       this.definitions.set(moduleId, {
@@ -158,6 +167,7 @@ interface Definition {
 }
 
 interface Module {
+  id: string;
   dependencies: string[];
   factory: (...args: unknown[]) => unknown;
   exports?: Promise<unknown>;