ErrorInfo.cause: must be an errorinfo if present, not a string

ErrorInfo.cause should never have been permitted to be an Error or a
string in the typings; if present it must be an ErrorInfo (spec TI1).

AFAICS it's never a string, there were some places where it could be an
Error which I've fixed.

Author: SimonWoolf

ably.d.ts

@@ -3693,7 +3693,7 @@ export declare class ErrorInfo extends Error {
   /**
    * The underlying cause of the error, where applicable.
    */
-  cause?: string | Error | ErrorInfo;
+  cause?: ErrorInfo;
 
   /**
    * Construct an ErrorInfo object.
@@ -3703,5 +3703,5 @@ export declare class ErrorInfo extends Error {
    * @param statusCode - HTTP Status Code corresponding to this error.
    * @param cause - The underlying cause of the error.
    */
-  constructor(message: string, code: number, statusCode: number, cause?: string | Error | ErrorInfo);
+  constructor(message: string, code: number, statusCode: number, cause?: ErrorInfo);
 }

src/common/lib/client/realtimechannel.ts

@@ -77,7 +77,7 @@ class RealtimeChannel extends EventEmitter {
     attachSerial: string | null | undefined;
     channelSerial: string | null | undefined;
   };
-  errorReason: ErrorInfo | string | null;
+  errorReason: ErrorInfo | null;
   _mode = 0;
   _attachResume: boolean;
   _decodingContext: EncodingDecodingContext;

src/common/lib/types/errorinfo.ts

@@ -5,7 +5,7 @@ import * as API from '../../../../ably';
 export interface IPartialErrorInfo extends Error {
   code: number | null;
   statusCode?: number;
-  cause?: string | Error | ErrorInfo;
+  cause?: ErrorInfo | PartialErrorInfo;
   href?: string;
 }
 
@@ -35,10 +35,10 @@ export interface IConvertibleToPartialErrorInfo {
 export default class ErrorInfo extends Error implements IPartialErrorInfo, API.ErrorInfo {
   code: number;
   statusCode: number;
-  cause?: string | Error | ErrorInfo;
+  cause?: ErrorInfo;
   href?: string;
 
-  constructor(message: string, code: number, statusCode: number, cause?: string | Error | ErrorInfo) {
+  constructor(message: string, code: number, statusCode: number, cause?: ErrorInfo) {
     super(message);
     if (typeof Object.setPrototypeOf !== 'undefined') {
       Object.setPrototypeOf(this, ErrorInfo.prototype);
@@ -68,10 +68,10 @@ export default class ErrorInfo extends Error implements IPartialErrorInfo, API.E
 export class PartialErrorInfo extends Error implements IPartialErrorInfo {
   code: number | null;
   statusCode?: number;
-  cause?: string | Error | ErrorInfo;
+  cause?: ErrorInfo | PartialErrorInfo;
   href?: string;
 
-  constructor(message: string, code: number | null, statusCode?: number, cause?: string | Error | ErrorInfo) {
+  constructor(message: string, code: number | null, statusCode?: number, cause?: ErrorInfo | PartialErrorInfo) {
     super(message);
     if (typeof Object.setPrototypeOf !== 'undefined') {
       Object.setPrototypeOf(this, PartialErrorInfo.prototype);

src/platform/nodejs/lib/util/crypto.ts

@@ -180,7 +180,7 @@ var createCryptoClass = function (bufferUtils: typeof BufferUtils) {
       try {
         return generateRandom((keyLength || DEFAULT_KEYLENGTH) / 8);
       } catch (err) {
-        throw new ErrorInfo('Failed to generate random key: ' + (err as Error).message, 500, 50000, err as Error);
+        throw new ErrorInfo('Failed to generate random key: ' + (err as Error).message, 500, 50000);
       }
     }
 

src/platform/web/lib/util/crypto.ts

@@ -143,7 +143,7 @@ var createCryptoClass = function (config: IPlatformConfig, bufferUtils: typeof B
       try {
         return config.getRandomArrayBuffer((keyLength || DEFAULT_KEYLENGTH) / 8);
       } catch (err) {
-        throw new ErrorInfo('Failed to generate random key: ' + (err as Error).message, 400, 50000, err as Error);
+        throw new ErrorInfo('Failed to generate random key: ' + (err as Error).message, 400, 50000);
       }
     }
 

src/plugins/push/getW3CDeviceDetails.ts

@@ -84,7 +84,9 @@ export async function getW3CPushDeviceDetails(machine: ActivationStateMachine) {
     machine.handleEvent(new GotPushDeviceDetails());
   } catch (err) {
     machine.handleEvent(
-      new GettingPushDeviceDetailsFailed(new ErrorInfo('Failed to register service worker', 50000, 500, err as Error)),
+      new GettingPushDeviceDetailsFailed(
+        new ErrorInfo('Failed to register service worker: ' + (err as Error).message, 50000, 500),
+      ),
     );
   }
 }