Add additional isCodec checks to error/event .is (#4840)

Author: jacogr

CHANGELOG.md

@@ -6,6 +6,7 @@ Changes:
 
 - Adjust extrinsic inspect for signed/unsigned
 - Add support for `mmr_generateBatchProof` RPC
+- Add additional `isCodec` checks to error/event `.is`
 
 
 ## 8.4.2 May 15, 2022

packages/types/src/metadata/decorate/errors/index.ts

@@ -7,7 +7,7 @@ import type { DispatchErrorModule, DispatchErrorModuleU8a, MetadataLatest, SiFie
 import type { PortableRegistry } from '../../../metadata';
 import type { Errors, IsError } from '../types';
 
-import { isU8a, lazyMethod, objectSpread, stringCamelCase } from '@polkadot/util';
+import { isCodec, isU8a, lazyMethod, objectSpread, stringCamelCase } from '@polkadot/util';
 
 import { lazyVariants } from '../../../create/lazy';
 import { objectNameToString } from '../util';
@@ -39,11 +39,14 @@ export function decorateErrors (registry: Registry, { lookup, pallets }: Metadat
 
       lazyMethod(result, stringCamelCase(name), () =>
         lazyVariants(lookup, errors.unwrap(), objectNameToString, (variant: SiVariant): IsError => ({
-          is: ({ error, index }: DispatchErrorModule | DispatchErrorModuleU8a) =>
-            index.eq(sectionIndex) && (
-              isU8a(error)
-                ? error[0] === variant.index.toNumber()
-                : error.eq(variant.index)
+          // We sprinkle in isCodec & isU8a to ensure we are dealing with the correct objects
+          is: (errorMod: DispatchErrorModule | DispatchErrorModuleU8a) =>
+            isCodec(errorMod) &&
+            isCodec(errorMod.index) &&
+            errorMod.index.eq(sectionIndex) && (
+              isU8a(errorMod.error)
+                ? errorMod.error[0] === variant.index.toNumber()
+                : isCodec(errorMod.error) && errorMod.error.eq(variant.index)
             ),
           meta: registry.createTypeUnsafe('ErrorMetadataLatest', [variantToMeta(lookup, variant)])
         }))

packages/types/src/metadata/decorate/events/index.spec.ts

@@ -1,9 +1,6 @@
 // Copyright 2017-2022 @polkadot/types authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
-import type { AnyTuple } from '@polkadot/types-codec/types';
-import type { IEvent } from '../../../types';
-
 import rpcMetadata from '@polkadot/types-support/metadata/static-substrate';
 
 import { TypeRegistry } from '../../../create';
@@ -42,7 +39,7 @@ describe('decorateEvents', (): void => {
 
   it('should check against a specific error', (): void => {
     expect(
-      events.system.ExtrinsicSuccess.is({ index: [0, 0] } as unknown as IEvent<AnyTuple>)
+      events.system.ExtrinsicSuccess.is(registry.createType('Event', { index: [0, 0] }))
     ).toBe(true);
   });
 });

packages/types/src/metadata/decorate/events/index.ts

@@ -6,7 +6,7 @@ import type { MetadataLatest, PalletMetadataLatest, SiVariant } from '../../../i
 import type { IEvent } from '../../../types';
 import type { Events, IsEvent } from '../types';
 
-import { lazyMethod, stringCamelCase } from '@polkadot/util';
+import { isCodec, isU8a, lazyMethod, stringCamelCase } from '@polkadot/util';
 
 import { lazyVariants } from '../../../create/lazy';
 import { variantToMeta } from '../errors';
@@ -27,7 +27,10 @@ export function decorateEvents (registry: Registry, { lookup, pallets }: Metadat
 
     lazyMethod(result, stringCamelCase(name), () =>
       lazyVariants(lookup, events.unwrap(), objectNameToString, (variant: SiVariant): IsEvent<AnyTuple> => ({
+        // We sprinkle in isCodec & isU8a to ensure we are dealing with the correct objects
         is: <T extends AnyTuple> (eventRecord: IEvent<AnyTuple>): eventRecord is IEvent<T> =>
+          isCodec(eventRecord) &&
+          isU8a(eventRecord.index) &&
           sectionIndex === eventRecord.index[0] &&
           variant.index.eq(eventRecord.index[1]),
         meta: registry.createTypeUnsafe('EventMetadataLatest', [variantToMeta(lookup, variant)])