execute: inline collectAndExecuteSubfields function (#3083)

src/execution/execute.js

@@ -1017,6 +1017,9 @@ function completeObjectValue(
   path: Path,
   result: mixed,
 ): PromiseOrValue<ObjMap<mixed>> {
+  // Collect sub-fields to execute to complete this value.
+  const subFieldNodes = collectSubfields(exeContext, returnType, fieldNodes);
+
   // If there is an isTypeOf predicate function, call it with the
   // current result. If isTypeOf returns false, then raise an error rather
   // than continuing execution.
@@ -1028,12 +1031,12 @@ function completeObjectValue(
         if (!resolvedIsTypeOf) {
           throw invalidReturnTypeError(returnType, result, fieldNodes);
         }
-        return collectAndExecuteSubfields(
+        return executeFields(
           exeContext,
           returnType,
-          fieldNodes,
-          path,
           result,
+          path,
+          subFieldNodes,
         );
       });
     }
@@ -1043,13 +1046,7 @@ function completeObjectValue(
     }
   }
 
-  return collectAndExecuteSubfields(
-    exeContext,
-    returnType,
-    fieldNodes,
-    path,
-    result,
-  );
+  return executeFields(exeContext, returnType, result, path, subFieldNodes);
 }
 
 function invalidReturnTypeError(
@@ -1063,18 +1060,6 @@ function invalidReturnTypeError(
   );
 }
 
-function collectAndExecuteSubfields(
-  exeContext: ExecutionContext,
-  returnType: GraphQLObjectType,
-  fieldNodes: $ReadOnlyArray<FieldNode>,
-  path: Path,
-  result: mixed,
-): PromiseOrValue<ObjMap<mixed>> {
-  // Collect sub-fields to execute to complete this value.
-  const subFieldNodes = collectSubfields(exeContext, returnType, fieldNodes);
-  return executeFields(exeContext, returnType, result, path, subFieldNodes);
-}
-
 /**
  * A memoized collection of relevant subfields with regard to the return
  * type. Memoizing ensures the subfields are not repeatedly calculated, which