From dfb583289a0856f7bfa0fd4a986e2d7876a7b840 Mon Sep 17 00:00:00 2001
From: Purin1410 <ngminhkhoayj2706@gmail.com>
Date: Wed, 12 Aug 2026 02:11:55 +0700
Subject: [PATCH] fix(ts-sdk): align execution price calculation

---
 sdks/typescript/pmxt/client.ts                | 13 +--
 .../execution-price-detailed-local.test.ts    | 80 +++++++++++++++++++
 2 files changed, 82 insertions(+), 11 deletions(-)

diff --git a/sdks/typescript/pmxt/client.ts b/sdks/typescript/pmxt/client.ts
index 04ddc27f..690d7262 100644
--- a/sdks/typescript/pmxt/client.ts
+++ b/sdks/typescript/pmxt/client.ts
@@ -2894,17 +2894,8 @@ export abstract class Exchange {
      * @returns The volume-weighted average price, or 0 if insufficient liquidity
      */
     getExecutionPrice(orderBook: OrderBook, side: 'buy' | 'sell', amount: number): number {
-        const levels = side === 'buy' ? orderBook.asks : orderBook.bids;
-        let remaining = amount;
-        let totalCost = 0;
-        for (const level of levels) {
-            const fill = Math.min(remaining, level.size);
-            totalCost += fill * level.price;
-            remaining -= fill;
-            if (remaining <= 0) break;
-        }
-        if (remaining > 0) return 0;
-        return totalCost / amount;
+        const result = this.getExecutionPriceDetailed(orderBook, side, amount);
+        return result.fullyFilled ? result.price : 0;
     }
 
     /**
diff --git a/sdks/typescript/tests/execution-price-detailed-local.test.ts b/sdks/typescript/tests/execution-price-detailed-local.test.ts
index 423e46f8..16c37101 100644
--- a/sdks/typescript/tests/execution-price-detailed-local.test.ts
+++ b/sdks/typescript/tests/execution-price-detailed-local.test.ts
@@ -35,3 +35,83 @@ describe('getExecutionPriceDetailed', () => {
         });
     });
 });
+
+describe('getExecutionPrice', () => {
+    it('requires full fill and sorts asks before averaging buys', () => {
+        const client = new Polymarket({ autoStartServer: false });
+        const price = client.getExecutionPrice(
+            {
+                bids: [],
+                asks: [
+                    { price: 0.52, size: 4 },
+                    { price: 0.5, size: 6 },
+                ],
+            },
+            'buy',
+            8
+        );
+
+        expect(price).toBe(0.505);
+    });
+
+    it('requires full fill and sorts bids before averaging sells', () => {
+        const client = new Polymarket({ autoStartServer: false });
+        const price = client.getExecutionPrice(
+            {
+                bids: [
+                    { price: 0.41, size: 5 },
+                    { price: 0.43, size: 10 },
+                ],
+                asks: [],
+            },
+            'sell',
+            8
+        );
+
+        expect(price).toBe(0.43);
+    });
+
+    it('returns 0 when order cannot be fully filled', () => {
+        const client = new Polymarket({ autoStartServer: false });
+        const price = client.getExecutionPrice(
+            {
+                bids: [{ price: 0.42, size: 2 }],
+                asks: [],
+            },
+            'sell',
+            5
+        );
+
+        expect(price).toBe(0);
+    });
+
+    it('matches detailed-price validation for non-positive amount', () => {
+        const client = new Polymarket({ autoStartServer: false });
+        const emptyBook = { bids: [], asks: [] };
+
+        expect(() => client.getExecutionPrice(emptyBook, 'buy', 0)).toThrow(
+            'Amount must be greater than 0'
+        );
+        expect(() => client.getExecutionPriceDetailed(emptyBook, 'buy', -1)).toThrow(
+            'Amount must be greater than 0'
+        );
+    });
+
+    it('ignores non-positive level sizes before computing execution price', () => {
+        const client = new Polymarket({ autoStartServer: false });
+        const price = client.getExecutionPrice(
+            {
+                bids: [],
+                asks: [
+                    { price: 0.52, size: -1 },
+                    { price: 0.5, size: 0 },
+                    { price: 0.48, size: 8 },
+                ],
+            },
+            'buy',
+            8
+        );
+
+        expect(price).toBe(0.48);
+    });
+});