enhancement: remove extra ticks (#3754)

Promise resolution order changes in some instances, resulting in different orders for some errors within the errors array, as well as in different values of hasNext within incremental delivery payloads.

This PR introduces an async `completePromisedValue` helper function rather than using a promise chain (see below links).

https://github.com/tc39/proposal-faster-promise-adoption
tc39/ecma262#2770
tc39/ecma262#2772
tc39/ecma262#1250
https://v8.dev/blog/fast-async

Depends on #3793

Author: yaacovCR

src/execution/__tests__/nonnull-test.ts

@@ -259,6 +259,16 @@ describe('Execute: handles non-nullable types', () => {
             path: ['syncNest', 'syncNest', 'sync'],
             locations: [{ line: 6, column: 22 }],
           },
+          {
+            message: promiseError.message,
+            path: ['syncNest', 'promise'],
+            locations: [{ line: 5, column: 11 }],
+          },
+          {
+            message: promiseError.message,
+            path: ['syncNest', 'syncNest', 'promise'],
+            locations: [{ line: 6, column: 27 }],
+          },
           {
             message: syncError.message,
             path: ['syncNest', 'promiseNest', 'sync'],
@@ -274,21 +284,6 @@ describe('Execute: handles non-nullable types', () => {
             path: ['promiseNest', 'syncNest', 'sync'],
             locations: [{ line: 12, column: 22 }],
           },
-          {
-            message: promiseError.message,
-            path: ['syncNest', 'promise'],
-            locations: [{ line: 5, column: 11 }],
-          },
-          {
-            message: promiseError.message,
-            path: ['syncNest', 'syncNest', 'promise'],
-            locations: [{ line: 6, column: 27 }],
-          },
-          {
-            message: syncError.message,
-            path: ['promiseNest', 'promiseNest', 'sync'],
-            locations: [{ line: 13, column: 25 }],
-          },
           {
             message: promiseError.message,
             path: ['syncNest', 'promiseNest', 'promise'],
@@ -304,6 +299,11 @@ describe('Execute: handles non-nullable types', () => {
             path: ['promiseNest', 'syncNest', 'promise'],
             locations: [{ line: 12, column: 27 }],
           },
+          {
+            message: syncError.message,
+            path: ['promiseNest', 'promiseNest', 'sync'],
+            locations: [{ line: 13, column: 25 }],
+          },
           {
             message: promiseError.message,
             path: ['promiseNest', 'promiseNest', 'promise'],

src/execution/execute.ts

@@ -526,15 +526,14 @@ function executeField(
     const result = resolveFn(source, args, contextValue, info);
 
     if (isPromise(result)) {
-      const completed = result.then((resolved) =>
-        completeValue(exeContext, returnType, fieldNodes, info, path, resolved),
+      return completePromisedValue(
+        exeContext,
+        returnType,
+        fieldNodes,
+        info,
+        path,
+        result,
       );
-      // Note: we don't rely on a `catch` method, but we do expect "thenable"
-      // to take a second callback for the error case.
-      return completed.then(undefined, (rawError) => {
-        const error = locatedError(rawError, fieldNodes, pathToArray(path));
-        return handleFieldError(error, returnType, errors);
-      });
     }
 
     const completed = completeValue(
@@ -712,6 +711,36 @@ function completeValue(
   );
 }
 
+async function completePromisedValue(
+  exeContext: ExecutionContext,
+  returnType: GraphQLOutputType,
+  fieldNodes: ReadonlyArray<FieldNode>,
+  info: GraphQLResolveInfo,
+  path: Path,
+  result: Promise<unknown>,
+): Promise<unknown> {
+  try {
+    const resolved = await result;
+    let completed = completeValue(
+      exeContext,
+      returnType,
+      fieldNodes,
+      info,
+      path,
+      resolved,
+    );
+    if (isPromise(completed)) {
+      // see: https://github.com/tc39/proposal-faster-promise-adoption
+      // it is faster to await a promise prior to returning it from an async function
+      completed = await completed;
+    }
+    return completed;
+  } catch (rawError) {
+    const error = locatedError(rawError, fieldNodes, pathToArray(path));
+    return handleFieldError(error, returnType, exeContext.errors);
+  }
+}
+
 /**
  * Complete a async iterator value by completing the result and calling
  * recursively until all the results are completed.
@@ -845,17 +874,15 @@ function completeListItemValue(
   itemPath: Path,
 ): boolean {
   if (isPromise(item)) {
-    const completedItem = item.then((resolved) =>
-      completeValue(exeContext, itemType, fieldNodes, info, itemPath, resolved),
-    );
-
-    // Note: we don't rely on a `catch` method, but we do expect "thenable"
-    // to take a second callback for the error case.
     completedResults.push(
-      completedItem.then(undefined, (rawError) => {
-        const error = locatedError(rawError, fieldNodes, pathToArray(itemPath));
-        return handleFieldError(error, itemType, errors);
-      }),
+      completePromisedValue(
+        exeContext,
+        itemType,
+        fieldNodes,
+        info,
+        itemPath,
+        item,
+      ),
     );
 
     return true;