Large file upload task - Add UploadResult object

docs/tasks/LargeFileUploadTask.md

@@ -129,3 +129,19 @@ async function largeFileUpload(client, file) {
 	}
 }
 ```
+
+## Cancelling a largeFileUpload task
+
+_Cancelling an upload session sends a DELETE request to the upload session URL_
+
+```typescript
+const cancelResponse = await uploadTask.cancel();
+```
+
+## Get the largeFileUpload session
+
+_Returns the largeFileUpload session information containing the URL, expiry date and cancellation status of the task_
+
+```typescript
+const uploadsession: LargeFileUploadSession = uploadTask.getUploadSession();
+```

src/middleware/AuthenticationHandler.ts

@@ -69,11 +69,11 @@ export class AuthenticationHandler implements Middleware {
 			}
 			let authenticationProvider: AuthenticationProvider;
 			let authenticationProviderOptions: AuthenticationProviderOptions;
-			if (typeof options !== "undefined") {
+			if (options) {
 				authenticationProvider = options.authenticationProvider;
 				authenticationProviderOptions = options.authenticationProviderOptions;
 			}
-			if (typeof authenticationProvider === "undefined") {
+			if (!authenticationProvider) {
 				authenticationProvider = this.authenticationProvider;
 			}
 			const token: string = await authenticationProvider.getAccessToken(authenticationProviderOptions);