Ensure metadata.toJSON applies type aliasses (#3243)

CHANGELOG.md

@@ -19,6 +19,7 @@ Changes:
 - Add types for the new gilt module
 - Upgrade to the latest Substrate metadata
 - Adjust package detection to check for local monorepo dependencies
+- Ensure that metadata `.toJSON()` does apply type aliasses
 
 
 ## 3.10.2 Feb 23, 2021

packages/metadata/src/MetadataVersioned.ts

@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 
 import type { MetadataAll, MetadataLatest, MetadataV9, MetadataV10, MetadataV11, MetadataV12 } from '@polkadot/types/interfaces/metadata';
-import type { Registry } from '@polkadot/types/types';
+import type { AnyJson, Registry } from '@polkadot/types/types';
 
 import { Struct } from '@polkadot/types/codec';
 import { assert } from '@polkadot/util';
@@ -126,4 +126,16 @@ export class MetadataVersioned extends Struct {
   public getUniqTypes (throwError: boolean): string[] {
     return getUniqTypes(this.registry, this.asLatest, throwError);
   }
+
+  /**
+   * @description Converts the Object to JSON, typically used for RPC transfers
+   */
+  public toJSON (): Record<string, AnyJson> {
+    // HACK(y): ensure that we apply the aliasses if we have not done so already, this is
+    // needed to ensure we have the overrides as intended (only applied in toLatest)
+    // eslint-disable-next-line no-unused-expressions
+    this.asLatest;
+
+    return super.toJSON();
+  }
 }