Step 8.2: Fix wiring of jest test setup to avoid import cycle issues

test/setup/setupManualMocks.ts

@@ -0,0 +1,55 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { TextDecoder, TextEncoder } from "util";
+
+// jest 27 removes setImmediate from jsdom
+// polyfill until setImmediate use in client can be removed
+// @ts-ignore - we know the contract is wrong. That's why we're stubbing it.
+global.setImmediate = callback => setTimeout(callback, 0);
+
+// Stub ResizeObserver
+// @ts-ignore - we know it's a duplicate (that's why we're stubbing it)
+class ResizeObserver {
+    observe() {} // do nothing
+    unobserve() {} // do nothing
+    disconnect() {} // do nothing
+}
+window.ResizeObserver = ResizeObserver;
+
+// matchMedia is not included in jsdom
+const mockMatchMedia = jest.fn().mockImplementation(query => ({
+    matches: false,
+    media: query,
+    onchange: null,
+    addListener: jest.fn(), // Deprecated
+    removeListener: jest.fn(), // Deprecated
+    addEventListener: jest.fn(),
+    removeEventListener: jest.fn(),
+    dispatchEvent: jest.fn(),
+}));
+global.matchMedia = mockMatchMedia;
+
+// maplibre requires a createObjectURL mock
+global.URL.createObjectURL = jest.fn();
+
+// polyfilling TextEncoder as it is not available on JSDOM
+// view https://github.com/facebook/jest/issues/9983
+global.TextEncoder = TextEncoder;
+global.TextDecoder = TextDecoder;
+
+// prevent errors whenever a component tries to manually scroll.
+window.HTMLElement.prototype.scrollIntoView = jest.fn();