feat: propagate data.cause as cause in JsonRpcError constructor

jest.config.js

@@ -45,10 +45,10 @@ module.exports = {
   // An object that configures minimum threshold enforcement for coverage results
   coverageThreshold: {
     global: {
-      branches: 92.64,
+      branches: 93.05,
       functions: 94.44,
-      lines: 92.85,
-      statements: 92.85,
+      lines: 92.96,
+      statements: 92.96,
     },
   },
 

src/classes.ts

@@ -2,7 +2,7 @@ import type {
   Json,
   JsonRpcError as SerializedJsonRpcError,
 } from '@metamask/utils';
-import { isPlainObject } from '@metamask/utils';
+import { hasProperty, isObject, isPlainObject } from '@metamask/utils';
 import safeStringify from 'fast-safe-stringify';
 
 import type { OptionalDataWithOptionalCause } from './utils';
@@ -19,6 +19,9 @@ export type { SerializedJsonRpcError };
 export class JsonRpcError<
   Data extends OptionalDataWithOptionalCause,
 > extends Error {
+  // This can be removed when tsconfig lib and/or target have changed to >=es2022
+  public cause: OptionalDataWithOptionalCause;
+
   public code: number;
 
   public data?: Data;
@@ -36,6 +39,13 @@ export class JsonRpcError<
     this.code = code;
     if (data !== undefined) {
       this.data = data;
+      if (
+        isObject(data) &&
+        hasProperty(data, 'cause') &&
+        isObject(data.cause)
+      ) {
+        this.cause = data.cause;
+      }
     }
   }
 

tsconfig.json

@@ -3,6 +3,7 @@
     "esModuleInterop": true,
     "exactOptionalPropertyTypes": true,
     "forceConsistentCasingInFileNames": true,
+    // Remove custom `cause` field from JsonRpcError when updating
     "lib": ["ES2020"],
     "module": "CommonJS",
     "moduleResolution": "node",