add test simx

localtypings/pxtarget.d.ts

@@ -291,6 +291,9 @@ declare namespace pxt {
             // don't recycle the iframe between runs
             permanent?: boolean;
         }>;
+        // This is for testing new simulator extensions before adding them to targetconfig.json.
+        // DO NOT SHIP SIMULATOR EXTENSIONS HERE. Add them to targetconfig.json/approvedRepoLib instead.
+        testSimulatorExtensions?: pxt.Map<SimulatorExtensionConfig>;
     }
 
     interface TargetCompileService {

pxtsim/simdriver.ts

@@ -159,8 +159,10 @@ namespace pxsim {
                     simx.url = new URL(simx.index, simx.devUrl).toString();
                 } else {
                     const simUrl = this.getSimUrl();
+                    // Ensure we preserve upload target path (/app/<sha>---simulator)
+                    const simPath = simUrl.pathname.replace(/---?.*/, "");
                     // Construct the path. The "-" element delineates the extension key from the resource name.
-                    const simxPath = ["simx", key, "-", simx.index].join("/");
+                    const simxPath = [simPath, "simx", key, "-", simx.index].join("/");
                     simx.url = new URL(simxPath, simUrl.origin).toString();
                 }
 

webapp/src/simulator.ts

@@ -80,6 +80,16 @@ export async function initAsync(root: HTMLElement, cfg: SimulatorConfig) {
             permanent: true, // default to true
             ...e.v
         });
+    // Add in test simulator extensions
+    Object.entries(pxt.appTarget?.simulator?.testSimulatorExtensions || {})
+        .map(([k, v]) => ({ k: k, v: v as pxt.SimulatorExtensionConfig }))
+        .filter(e => !!e.v)
+        .forEach(e => simulatorExtensions[e.k] = {
+            index: "index.html", // default to index.html
+            aspectRatio: pxt.appTarget.simulator.aspectRatio || 1.22, // fallback to 1.22
+            permanent: true, // default to true
+            ...e.v
+        });
 
     let options: pxsim.SimulatorDriverOptions = {
         restart: () => cfg.restartSimulator(),