fix: Allow null in the endowment:assets handlers return value (#3056)

Author: GuillaumeRx

packages/examples/packages/browserify-plugin/snap.manifest.json

@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "GI7+exBM57/V+zc9afQYloOJkf31QC4QQ4J/FCjTkp0=",
+    "shasum": "h2/tYCy6l8S2zP9EdqxHKc0WSftxxnkP60i8d58vbno=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",

packages/examples/packages/browserify/snap.manifest.json

@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "kVPM+Ft1gxNWF59oCgW0MRN1DuA7kVyXwIdMbGec3aI=",
+    "shasum": "5mzSECxLy9lFHEwzmvRpjs0xL2TG0kTR2QXIjjavRTo=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",

packages/snaps-controllers/src/snaps/SnapController.ts

@@ -3689,7 +3689,7 @@ export class SnapController extends BaseController<
     const { assets: requestedAssets } = requestedParams;
 
     const filteredAssets = Object.keys(assets).reduce<
-      Record<CaipAssetType, FungibleAssetMetadata>
+      Record<CaipAssetType, FungibleAssetMetadata | null>
     >((accumulator, assetType) => {
       const castAssetType = assetType as CaipAssetType;
       const isValid =

packages/snaps-sdk/src/types/handlers/assets-conversion.ts

@@ -5,6 +5,7 @@ import {
   string,
   optional,
   record,
+  nullable,
 } from '@metamask/superstruct';
 import { CaipAssetTypeStruct, type CaipAssetType } from '@metamask/utils';
 
@@ -17,7 +18,7 @@ export const AssetConversionStruct = object({
 export const OnAssetsConversionResponseStruct = object({
   conversionRates: record(
     CaipAssetTypeStruct,
-    record(CaipAssetTypeStruct, AssetConversionStruct),
+    record(CaipAssetTypeStruct, nullable(AssetConversionStruct)),
   ),
 });
 
@@ -40,11 +41,11 @@ export type OnAssetsConversionHandler = (
 /**
  * The response from the conversion query, containing rates about each requested asset pair.
  *
- * @property conversionRates - A nested object with two CAIP-19 keys that contains a conversion rate between the two keys.
+ * @property conversionRates - A nested object with two CAIP-19 keys that contains a conversion rate or null between the two keys.
  */
 export type OnAssetsConversionResponse = {
   conversionRates: Record<
     CaipAssetType,
-    Record<CaipAssetType, AssetConversion>
+    Record<CaipAssetType, AssetConversion | null>
   >;
 };

packages/snaps-sdk/src/types/handlers/assets-lookup.ts

@@ -8,6 +8,7 @@ import {
   refine,
   string,
   record,
+  nullable,
 } from '@metamask/superstruct';
 import {
   assert,
@@ -46,7 +47,7 @@ export const FungibleAssetMetadataStruct = object({
 });
 
 export const OnAssetsLookupResponseStruct = object({
-  assets: record(CaipAssetTypeStruct, FungibleAssetMetadataStruct),
+  assets: record(CaipAssetTypeStruct, nullable(FungibleAssetMetadataStruct)),
 });
 
 export type FungibleAssetMetadata = Infer<typeof FungibleAssetMetadataStruct>;
@@ -68,8 +69,8 @@ export type OnAssetsLookupHandler = (
 /**
  * The response from the query, containing metadata about each requested asset.
  *
- * @property assets - An object containing a mapping between the CAIP-19 key and a metadata object.
+ * @property assets - An object containing a mapping between the CAIP-19 key and a metadata object or null.
  */
 export type OnAssetsLookupResponse = {
-  assets: Record<CaipAssetType, FungibleAssetMetadata>;
+  assets: Record<CaipAssetType, FungibleAssetMetadata | null>;
 };