From 0b1ca1ae29722101676d98c01d757ed6947f4201 Mon Sep 17 00:00:00 2001
From: Joe Clark <jclark@openfn.org>
Date: Tue, 16 Dec 2025 11:01:45 +0000
Subject: [PATCH] experiment with custom promise

---
 packages/runtime/src/execute/context.ts | 19 +++++++++++++++++++
 packages/runtime/test/errors.test.ts    | 22 ++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/packages/runtime/src/execute/context.ts b/packages/runtime/src/execute/context.ts
index 5a644ed34..8e80d65de 100644
--- a/packages/runtime/src/execute/context.ts
+++ b/packages/runtime/src/execute/context.ts
@@ -34,6 +34,24 @@ export default (
     }
   }
 
+  // TODO naming
+  class FancyPromise extends Promise {
+    constructor(resolve, reject) {
+      super(resolve, reject);
+    }
+    reject(e: any) {
+      console.log(' >>> custom reject!!');
+      if (!e || !(e instanceof Error)) {
+        // Force all promise objects to be errors
+        // This allows us to track positions
+        const error = new Error();
+        Object.assign(error, e);
+        return super.reject(error);
+      }
+      return super.reject(e);
+    }
+  }
+
   const context = vm.createContext(
     freezeAll(
       {
@@ -48,6 +66,7 @@ export default (
         setTimeout,
         state, // TODO will be dropped as a global one day, see https://github.com/OpenFn/kit/issues/17
         Buffer: SafeBuffer,
+        Promise: FancyPromise,
       },
       { state: true }
     ),
diff --git a/packages/runtime/test/errors.test.ts b/packages/runtime/test/errors.test.ts
index 2153e2607..21b01b8e9 100644
--- a/packages/runtime/test/errors.test.ts
+++ b/packages/runtime/test/errors.test.ts
@@ -313,6 +313,28 @@ test('fail on runtime TypeError', async (t) => {
   });
 });
 
+test.only('fail with position on rejected promise', async (t) => {
+  const expression = `export default [(s) => {
+  return Promise.reject({});
+}]`;
+
+  const result: any = await run(expression);
+  const error = result.errors['job-1'];
+  t.log(error);
+
+  // t.deepEqual(error, {
+  //   message: "TypeError: Cannot read properties of undefined (reading 'y')",
+  //   name: 'RuntimeError',
+  //   subtype: 'TypeError',
+  //   severity: 'fail',
+  //   source: 'runtime',
+  //   pos: {
+  //     column: 28,
+  //     line: 1,
+  //   },
+  // });
+});
+
 test('fail on runtime error with RangeError', async (t) => {
   const expression =
     'export default [(s) => Number.parseFloat("1").toFixed(-1)]';