fix: Converted global state for fromError to handle it internally.

*Related: #10
Reviewed-by: @tegefaulkes
[ci skip]

Author: addievo

src/utils/utils.ts

@@ -223,38 +223,41 @@ function parseJSONRPCMessage<T extends JSONValue>(
  * Polykey errors are handled by their inbuilt `toJSON` method , so this only
  * serialises other errors
  */
+const createReplacer = () => {
+  let withinErrorKey = false;
 
-let withinErrorKey = false;
-
-const replacer = (key: string, value: any) => {
-  if (key === 'error') {
-    withinErrorKey = true;
-  }
-  if (withinErrorKey && key !== 'code' && key !== 'message') {
-    if (value instanceof ErrorRPC) {
-      withinErrorKey = false;
-      return {
-        code: value.code,
-        message: value.description,
-        'data?': value.data,
-        type: value.constructor.name,
-      };
+  return (key: string, value: any) => {
+    if (key === 'error') {
+      withinErrorKey = true;
     }
-    if (value instanceof AggregateError) {
-      withinErrorKey = false;
-      return {
-        type: value.constructor.name,
-        data: {
-          errors: value.errors,
-          message: value.message,
-          stack: value.stack,
-        },
-      };
+    if (withinErrorKey && key !== 'code' && key !== 'message') {
+      if (value instanceof ErrorRPC) {
+        withinErrorKey = false;
+        return {
+          code: value.code,
+          message: value.description,
+          'data?': value.data,
+          type: value.constructor.name,
+        };
+      }
+      if (value instanceof AggregateError) {
+        withinErrorKey = false;
+        return {
+          type: value.constructor.name,
+          data: {
+            errors: value.errors,
+            message: value.message,
+            stack: value.stack,
+          },
+        };
+      }
     }
-  }
-  return value;
+    return value;
+  };
 };
 
+const replacer = createReplacer();
+
 /**
  * Serializes Error instances into RPC errors
  * Use this on the sending side to send exceptions