fix(longbridge): convert order writes to SDK Decimal

CONTRIBUTORS.md

@@ -49,6 +49,7 @@ work left a mark on it, you belong here.
 | | <a href="https://github.com/dbydd"><img src="https://github.com/dbydd.png" width="40" height="40" alt="@dbydd" /></a><br>[@dbydd](https://github.com/dbydd) | 🐛 🤔 🎨 | [Pi global + Workspace configuration layering and model reasoning capabilities (#662)](https://github.com/TraderAlice/OpenAlice/issues/662) — an unusually complete two-part reproduction that drove the native project-overlay architecture, safe migration of legacy `.pi-agent` state, and explicit reasoning-capability round trips in [#670](https://github.com/TraderAlice/OpenAlice/pull/670) |
 | | <a href="https://github.com/enderzcx"><img src="https://github.com/enderzcx.png" width="40" height="40" alt="@enderzcx" /></a><br>[@enderzcx](https://github.com/enderzcx) | 🐛 🤔 | [Bitget Classic account-state blind spots (#951)](https://github.com/TraderAlice/OpenAlice/pull/951) — traced healthy-looking unscoped CCXT reads that omitted USDT-M funds and conditional-order namespaces, leading to the in-house Classic account model and routing fix |
 | | <a href="https://github.com/roymeshulam"><img src="https://github.com/roymeshulam.png" width="40" height="40" alt="@roymeshulam" /></a><br>[@roymeshulam](https://github.com/roymeshulam) | 🐛 🤔 | [Telegram Connector startup hid the health endpoint (#639)](https://github.com/TraderAlice/OpenAlice/pull/639) — isolated adapter init blocking Guardian's probe and proposed listen-before-start plus keeping degraded `lastError`, reimplemented in-house in [#1078](https://github.com/TraderAlice/OpenAlice/pull/1078) |
+| | <a href="https://github.com/fanfpy"><img src="https://github.com/fanfpy.png" width="40" height="40" alt="@fanfpy" /></a><br>[@fanfpy](https://github.com/fanfpy) | 🐛 🤔 | [Longbridge submit/replace failed at the N-API Decimal boundary (#959)](https://github.com/TraderAlice/OpenAlice/issues/959) — traced `decimal.js` values being passed into the SDK's native Decimal fields and proposed converting at the write boundary ([#704](https://github.com/TraderAlice/OpenAlice/pull/704)), reimplemented in-house |
 
 ---
 

services/uta/src/domain/trading/brokers/longbridge/LongbridgeBroker.spec.ts

@@ -1,13 +1,26 @@
 import { describe, it, expect, vi, beforeEach } from 'vitest'
 import Decimal from 'decimal.js'
 import { Contract, Order } from '@traderalice/ibkr'
+import { Decimal as LongbridgeDecimal } from 'longbridge'
 import { LongbridgeBroker, ibkrOrderTypeToLb, ibkrTifToLb } from './LongbridgeBroker.js'
 import { makeContract, parseLbSymbol, resolveSymbol, mapLbOrderStatus } from './longbridge-contracts.js'
 import '../../contract-ext.js'
 
 // ==================== Longbridge SDK mock ====================
 
 vi.mock('longbridge', () => {
+  class MockLongbridgeDecimal {
+    private readonly value: string
+
+    constructor(value: string | number) {
+      this.value = String(value)
+    }
+
+    toString(): string {
+      return this.value
+    }
+  }
+
   // Numeric enum values mirror the const enum in node_modules/longbridge/index.d.ts.
   const OrderSide = { Unknown: 0, Buy: 1, Sell: 2 } as const
   const OrderType = {
@@ -18,6 +31,7 @@ vi.mock('longbridge', () => {
   const Market = { Unknown: 0, US: 1, HK: 2, CN: 3, SG: 4, Crypto: 5 } as const
 
   return {
+    Decimal: MockLongbridgeDecimal,
     Config: { fromApikey: vi.fn(() => ({ __config: true })) },
     TradeContext: {
       new: vi.fn(() => ({
@@ -44,6 +58,12 @@ vi.mock('longbridge', () => {
   }
 })
 
+function expectLongbridgeDecimal(value: unknown, expected: string): void {
+  expect(value).toBeInstanceOf(LongbridgeDecimal)
+  expect(value).not.toBeInstanceOf(Decimal)
+  expect(String(value)).toBe(expected)
+}
+
 // Helper: stamp mock contexts onto a freshly-constructed broker so we can
 // drive method outcomes without going through init().
 function attachMockContexts(broker: LongbridgeBroker): {
@@ -534,6 +554,48 @@ describe('LongbridgeBroker — getPositions()', () => {
 describe('LongbridgeBroker — placeOrder()', () => {
   beforeEach(() => vi.clearAllMocks())
 
+  it('converts decimal.js submit fields to SDK Decimal instances', async () => {
+    const broker = makeBroker()
+    const { trade } = attachMockContexts(broker)
+    trade.submitOrder.mockResolvedValue({ orderId: 'decimal-submit' })
+    const contract = makeContract('AAPL.US')
+    const order = new Order()
+    order.action = 'BUY'
+    order.orderType = 'TRAIL LIMIT'
+    order.totalQuantity = new Decimal('1.25')
+    order.lmtPrice = new Decimal('201.125')
+    order.auxPrice = new Decimal('199.875')
+    order.trailingPercent = new Decimal('1.5')
+    order.tif = 'DAY'
+
+    await broker.placeOrder(contract, order)
+
+    const sent = trade.submitOrder.mock.calls[0][0]
+    expectLongbridgeDecimal(sent.submittedQuantity, '1.25')
+    expectLongbridgeDecimal(sent.submittedPrice, '201.125')
+    expectLongbridgeDecimal(sent.triggerPrice, '199.875')
+    expectLongbridgeDecimal(sent.trailingPercent, '1.5')
+  })
+
+  it('preserves high-precision quantity without a JS number hop', async () => {
+    const broker = makeBroker()
+    const { trade } = attachMockContexts(broker)
+    trade.submitOrder.mockResolvedValue({ orderId: 'decimal-precise' })
+    const contract = makeContract('AAPL.US')
+    const order = new Order()
+    order.action = 'BUY'
+    order.orderType = 'LMT'
+    order.totalQuantity = new Decimal('123.4567890123456789')
+    order.lmtPrice = new Decimal('201.1250000000000001')
+    order.tif = 'DAY'
+
+    await broker.placeOrder(contract, order)
+
+    const sent = trade.submitOrder.mock.calls[0][0]
+    expectLongbridgeDecimal(sent.submittedQuantity, '123.4567890123456789')
+    expectLongbridgeDecimal(sent.submittedPrice, '201.1250000000000001')
+  })
+
   it('translates HK MKT → ELO (HK quirk)', async () => {
     const b = makeBroker()
     const { trade } = attachMockContexts(b)
@@ -702,6 +764,24 @@ describe('LongbridgeBroker — modifyOrder()', () => {
     const sent = trade.replaceOrder.mock.calls[0][0]
     expect(sent.orderId).toBe('ord-1')
     expect(sent.quantity.toString()).toBe('150')
+    expectLongbridgeDecimal(sent.quantity, '150')
+  })
+
+  it('converts decimal.js replacement fields to SDK Decimal instances', async () => {
+    const broker = makeBroker()
+    const { trade } = attachMockContexts(broker)
+    trade.replaceOrder.mockResolvedValue(undefined)
+
+    await broker.modifyOrder('ord-1', {
+      totalQuantity: new Decimal('2.5'),
+      lmtPrice: new Decimal('202.25'),
+      auxPrice: new Decimal('198.75'),
+    })
+
+    const sent = trade.replaceOrder.mock.calls[0][0]
+    expectLongbridgeDecimal(sent.quantity, '2.5')
+    expectLongbridgeDecimal(sent.price, '202.25')
+    expectLongbridgeDecimal(sent.triggerPrice, '198.75')
   })
 })
 

services/uta/src/domain/trading/brokers/longbridge/LongbridgeBroker.ts

@@ -19,6 +19,7 @@ import { z } from 'zod'
 import Decimal from 'decimal.js'
 import { Contract, ContractDescription, ContractDetails, Order, UNSET_DECIMAL } from '@traderalice/ibkr'
 import {
+  Decimal as LongbridgeDecimal,
   Config,
   TradeContext,
   QuoteContext,
@@ -68,6 +69,11 @@ import type {
 const DERIVATIVE_OPTION = 0
 const DERIVATIVE_WARRANT = 1
 
+/** Longbridge N-API writes require the SDK Decimal class, not decimal.js. */
+function toLongbridgeDecimal(value: Decimal): LongbridgeDecimal {
+  return new LongbridgeDecimal(value.toString())
+}
+
 // ==================== Order-type translation ====================
 
 /**
@@ -294,11 +300,11 @@ export class LongbridgeBroker implements IBroker {
       orderType: lbType,
       side,
       timeInForce: lbTif,
-      submittedQuantity: order.totalQuantity as unknown as never,  // SDK accepts decimal.js or its own Decimal
+      submittedQuantity: toLongbridgeDecimal(order.totalQuantity),
     }
-    if (!order.lmtPrice.equals(UNSET_DECIMAL)) opts.submittedPrice = order.lmtPrice as unknown as never
-    if (!order.auxPrice.equals(UNSET_DECIMAL)) opts.triggerPrice = order.auxPrice as unknown as never
-    if (!order.trailingPercent.equals(UNSET_DECIMAL)) opts.trailingPercent = order.trailingPercent as unknown as never
+    if (!order.lmtPrice.equals(UNSET_DECIMAL)) opts.submittedPrice = toLongbridgeDecimal(order.lmtPrice)
+    if (!order.auxPrice.equals(UNSET_DECIMAL)) opts.triggerPrice = toLongbridgeDecimal(order.auxPrice)
+    if (!order.trailingPercent.equals(UNSET_DECIMAL)) opts.trailingPercent = toLongbridgeDecimal(order.trailingPercent)
 
     try {
       const resp = await this.tradeCtx.submitOrder(opts)
@@ -318,13 +324,13 @@ export class LongbridgeBroker implements IBroker {
     }
     const opts: ReplaceOrderOptions = {
       orderId,
-      quantity: changes.totalQuantity as unknown as never,
+      quantity: toLongbridgeDecimal(changes.totalQuantity),
     }
     if (changes.lmtPrice != null && !changes.lmtPrice.equals(UNSET_DECIMAL)) {
-      opts.price = changes.lmtPrice as unknown as never
+      opts.price = toLongbridgeDecimal(changes.lmtPrice)
     }
     if (changes.auxPrice != null && !changes.auxPrice.equals(UNSET_DECIMAL)) {
-      opts.triggerPrice = changes.auxPrice as unknown as never
+      opts.triggerPrice = toLongbridgeDecimal(changes.auxPrice)
     }
     try {
       await this.tradeCtx.replaceOrder(opts)