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test/utils/listenersManager.ts

@@ -9,13 +9,13 @@ let firstTime = true;
  * The list of listeners that were present during the first time this manager is run.
  * These initial listeners are needed throughout the entire test suite, so we never remove them.
  */
-const initialListeners: unknown[] = [];
+const initialListeners: NodeJS.MessageListener[] = [];
 
 /**
  * The current listener that is only needed for the current test file.
  * We plan to delete it during the next test file, when it is no longer needed.
  */
-let currentListener;
+let currentListener: NodeJS.MessageListener | null;
 
 export function manageListeners() {
   if (firstTime) {

test/utils/mocks/mockContext.ts

@@ -5,11 +5,15 @@ import { mockCanvas } from "#test/utils/mocks/mockCanvas";
  */
 export const mockContext: any = {
   font: "",
-  //@ts-ignore
-  measureText: () => new TextMetrics(""),
+  measureText: () => {
+    return {};
+  },
   save: () => {},
   scale: () => {},
   clearRect: () => {},
+  fillRect: () => {},
+  fillText: () => {},
+  getImageData: () => {},
   canvas: mockCanvas,
   restore: () => {},
 };