TW: add types for Scratch.external

Author: GarboMuffin

tests/test-scratch-vm-extension-tw.js

@@ -174,3 +174,10 @@ Scratch.extensions.register({
     };
   }
 });
+
+Scratch.external.importModule(
+  "https://cdn.jsdelivr.net/npm/@mediapipe/[email protected]/face_detection.js"
+);
+Scratch.external.blob(
+  "https://cdn.jsdelivr.net/npm/@mediapipe/[email protected]/face_detection_short.binarypb"
+);

types/scratch-vm-extension.d.ts

@@ -106,6 +106,39 @@ declare namespace Scratch {
     const ROUND: 2;
     const SQUARE: 3;
   }
+  namespace external {
+    /**
+     * Import an ES module, like import().
+     * May be inlined at build-time.
+     * @param url Must be absolute and constant.
+     */
+    function importModule<T = unknown>(url: string): Promise<T>;
+    /**
+     * Returns the contents of a resource, like fetch(). Response headers may be missing.
+     * May be inlined at build-time.
+     * @param url Must be absolute and constant.
+     */
+    function fetch(url: string): Promise<Response>;
+    /**
+     * Returns the contents of a resource as a data: URL.
+     * May be inlined at build-time.
+     * @param url Must be absolute and constant.
+     */
+    function dataURL(url: string): Promise<string>;
+    /**
+     * Returns the contents of a resource as a Blob.
+     * May be inlined at build-time.
+     * @param url Must be absolute and constant.
+     */
+    function blob(url: string): Promise<Blob>;
+    /**
+     * Fetch a script and then evaluate it in an IIFE, returning an expression of your choice.
+     * May be inlined at build-time.
+     * @param url Must be absolute and constant.
+     * @param returnExpression JS expression to return, usually a variable name but could be an object instead. Must be constant.
+     */
+    function evalAndReturn<T = unknown>(url: string, returnExpression: string): Promise<T> | T;
+  }
 
   // Note that the 'B' in the BOOLEAN enums are capitalized in Scratch. It is not a typo in this file.