Merge pull request #6976 from Agoric/ta/fix-deeplyAwaited

improve types of fulfillment helpers
Agoric · Feb 12, 2023 · adc0836 · adc0836
2 parents 93e8bb9 + 2683f47
commit adc0836
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Showing 3 changed files with 34 additions and 7 deletions.
diff --git a/packages/inter-protocol/src/collect.js b/packages/inter-protocol/src/collect.js
@@ -3,7 +3,7 @@ const { fromEntries, keys, values } = Object;
 /** @type { <X, Y>(xs: X[], ys: Y[]) => [X, Y][]} */
 export const zip = (xs, ys) => harden(xs.map((x, i) => [x, ys[+i]]));
 
-/** @type { <K extends string, V>(obj: Record<K, ERef<V>>) => Promise<Record<K, V>> } */
+/** @type { <T extends Record<string, ERef<any>>>(obj: T) => Promise<{ [K in keyof T]: Awaited<T[K]>}> } */
 export const allValues = async obj => {
   const resolved = await Promise.all(values(obj));
   // @ts-expect-error cast

diff --git a/packages/internal/src/utils.js b/packages/internal/src/utils.js
@@ -248,18 +248,25 @@ export const bindAllMethods = obj =>
   );
 harden(bindAllMethods);
 
+/**
+ * @template T
+ * @typedef {{[KeyType in keyof T]: T[KeyType]} & {}} Simplify
+ * flatten the type output to improve type hints shown in editors
+ * https://github.com/sindresorhus/type-fest/blob/main/source/simplify.d.ts
+ */
+
+/**
+ * @typedef {(...args: any[]) => any} Callable
+ */
+
 /**
  * @template {{}} T
- * @typedef {{ [K in keyof T]: DeeplyAwaited<T[K]> }} DeeplyAwaitedObject
+ * @typedef {{ [K in keyof T]: T[K] extends Callable ? T[K] : DeeplyAwaited<T[K]> }} DeeplyAwaitedObject
  */
 
 /**
- * Caveats:
- * - doesn't recur within Promise results
- * - resulting type has wrapper in its name
- *
  * @template T
- * @typedef {T extends PromiseLike<any> ? Awaited<T> : T extends {} ? DeeplyAwaitedObject<T> : Awaited<T>} DeeplyAwaited
+ * @typedef {T extends PromiseLike<any> ? Awaited<T> : T extends {} ? Simplify<DeeplyAwaitedObject<T>> : Awaited<T>} DeeplyAwaited
  */
 
 /**

diff --git a/packages/internal/test/test-utils.js b/packages/internal/test/test-utils.js
@@ -2,6 +2,7 @@
 import test from 'ava';
 import '@endo/init';
 
+import { Far } from '@endo/marshal';
 import {
   fromUniqueEntries,
   objectMap,
@@ -10,6 +11,7 @@ import {
   whileTrue,
   untilTrue,
   forever,
+  deeplyFulfilledObject,
 } from '../src/utils.js';
 
 test('fromUniqueEntries', t => {
@@ -57,6 +59,24 @@ test('objectMap', t => {
   );
 });
 
+test('deeplyFulfilledObject', async t => {
+  const someFar = Far('somefar', { getAsync: () => Promise.resolve('async') });
+  const unfulfilled = harden({
+    obj1: {
+      obj2a: {
+        stringP: Promise.resolve('foo'),
+      },
+      obj2b: someFar,
+    },
+  });
+  const fulfilled = await deeplyFulfilledObject(unfulfilled);
+  // JS check that it's a now string
+  fulfilled.obj1.obj2a.stringP.length;
+  t.deepEqual(fulfilled, {
+    obj1: { obj2a: { stringP: 'foo' }, obj2b: someFar },
+  });
+});
+
 test('makeMeasureSeconds', async t => {
   const times = [1000.25, 2000.75, NaN];
   /** @type {() => number} */