feat: add ducktyping functions

src/Block.ts

@@ -33,7 +33,6 @@ export enum BlockType {
 }
 
 export class Block {
-  __type: 'Block';
   id: StorageId;
   chainId: StorageId;
   txId: string;
@@ -58,10 +57,6 @@ export class Block {
 
   state?: string;
 
-  constructor() {
-    this.__type = 'Block';
-  }
-
   getDataForSignature(): SignatureData {
     const {
       type,
@@ -179,3 +174,13 @@ export type BlockCommitments = {
   balanceCommitmentBlindFactor: any;
   amountCommitmentBlindFactor: any;
 };
+
+export function isBlock(val: any): boolean {
+  if (!val) return false;
+
+  // Ducktyping: maybe extend check with more fields
+  if (!val.type) return false;
+  if (!val.senderAmount) return false;
+
+  return true;
+}

src/Blockchain.ts

@@ -8,7 +8,6 @@ export enum AssetSymbol {
 }
 
 export class Blockchain {
-  __type: 'Blockchain';
   id: StorageId;
   leafId: StorageId | undefined;
   publicSig: SigPublicKey;
@@ -17,7 +16,6 @@ export class Blockchain {
   blocks: Block[] = [];
 
   constructor(publicSig: SigPublicKey, publicNtru?: NTRUPublicKey, symbol?: AssetSymbol) {
-    this.__type = 'Blockchain';
     this.publicSig = publicSig;
     this.publicNtru = publicNtru;
     this.assetSymbol = symbol || AssetSymbol.TXL;
@@ -51,3 +49,25 @@ export function fromBlockchainObject(obj: any) {
 export function deserializeBlock(block: object): Block {
   return fromBlockObject(block);
 }
+
+export function isBlockchain(val: any): boolean {
+  if (!val) return false;
+
+  // Ducktyping: maybe extend check with more fields
+  return Array.isArray(val.blocks);
+}
+
+export function isBlockchainRecord(val: any): boolean {
+  if (!val) return false;
+
+  const fields = Object.getOwnPropertyNames(val);
+
+  // an empty record is a valid record..
+  if (fields.length === 0) return true;
+
+  // test the first object if it is a blockchain
+  // if so the val behaves like a Record<string, Blockchain>
+  const testFirstChain = fields[0];
+
+  return isBlockchain(val[testFirstChain]);
+}

src/Transaction.ts

@@ -4,12 +4,10 @@ import { StorageId } from './Storage';
 import { AssetSymbol } from './Blockchain';
 
 export class Transaction {
-  __type: 'Transaction';
   id: StorageId;
   blocks: Block[] = [];
 
   constructor(symbol?: AssetSymbol) {
-    this.__type = 'Transaction';
     this.assetSymbol = symbol || AssetSymbol.TXL;
   }