From cdd32e9323069452a4d0345174b049be1c8e1069 Mon Sep 17 00:00:00 2001
From: edu-stx <116000646+edu-stx@users.noreply.github.com>
Date: Wed, 23 Nov 2022 14:49:25 +0000
Subject: [PATCH] feat: add payload type assertions (#1395)
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Adds assertion methods (i.e. type predicates) for the Payload type: `isTokenTransferPayload`, `isContractCallPayload`, `isSmartContractPayload`, `isPoisonPayload`, `isCoinbasePayload` — Thanks to @edu-stx
---
 packages/transactions/src/index.ts   |  5 +++++
 packages/transactions/src/payload.ts | 16 ++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/packages/transactions/src/index.ts b/packages/transactions/src/index.ts
index 34e6dc83e..57eb7e07f 100644
--- a/packages/transactions/src/index.ts
+++ b/packages/transactions/src/index.ts
@@ -18,6 +18,11 @@ export {
   PoisonPayload,
   CoinbasePayload,
   serializePayload,
+  isTokenTransferPayload,
+  isContractCallPayload,
+  isSmartContractPayload,
+  isPoisonPayload,
+  isCoinbasePayload,
 } from './payload';
 
 export {
diff --git a/packages/transactions/src/payload.ts b/packages/transactions/src/payload.ts
index 79eb216f0..1add10f44 100644
--- a/packages/transactions/src/payload.ts
+++ b/packages/transactions/src/payload.ts
@@ -24,6 +24,22 @@ export type Payload =
   | PoisonPayload
   | CoinbasePayload;
 
+export function isTokenTransferPayload(p: Payload): p is TokenTransferPayload {
+  return p.payloadType === PayloadType.TokenTransfer;
+}
+export function isContractCallPayload(p: Payload): p is ContractCallPayload {
+  return p.payloadType === PayloadType.ContractCall;
+}
+export function isSmartContractPayload(p: Payload): p is SmartContractPayload {
+  return p.payloadType === PayloadType.SmartContract;
+}
+export function isPoisonPayload(p: Payload): p is PoisonPayload {
+  return p.payloadType === PayloadType.PoisonMicroblock;
+}
+export function isCoinbasePayload(p: Payload): p is CoinbasePayload {
+  return p.payloadType === PayloadType.Coinbase;
+}
+
 export interface TokenTransferPayload {
   readonly type: StacksMessageType.Payload;
   readonly payloadType: PayloadType.TokenTransfer;