fix: protect bigints in axios payloads

src/starknet.ts

@@ -12,7 +12,7 @@ import type {
  GetTransactionStatusResponse,
  Transaction,
 } from './types';
-import { parse } from './utils/json';
+import { parse, stringify } from './utils/json';
 import { BigNumberish, toBN, toHex } from './utils/number';
 import { compressProgram, randomAddress } from './utils/starknet';
 
@@ -199,11 +199,15 @@ export function addTransaction(tx: Transaction): Promise<AddTransactionResponse>
 
  return new Promise((resolve, reject) => {
  axios
- .post(`${GATEWAY_URL}/add_transaction`, {
- ...tx,
- ...(Array.isArray(signature) && { signature }), // not needed on deploy tx
- ...(contract_address_salt && { contract_address_salt }), // not needed on invoke tx
- })
+ .post(
+ `${GATEWAY_URL}/add_transaction`,
+ stringify({
+ ...tx, // the tx can contain BigInts, so we use our own `stringify`
+ ...(Array.isArray(signature) && { signature }), // not needed on deploy tx
+ ...(contract_address_salt && { contract_address_salt }), // not needed on invoke tx
+ }),
+ { headers: { 'Content-Type': 'application/json' } }
+ )
  .then((resp: any) => {
  resolve(resp.data);
  })