chore: refactor promiseRecord (#6161)

* chore: refactor promiseRecord

* cleanup

packages/store/addon/-private/system/store.ts

@@ -40,22 +40,14 @@ import edBackburner from './backburner';
 import { RECORD_DATA_ERRORS, RECORD_DATA_STATE } from '@ember-data/canary-features';
 import { Record } from '../ts-interfaces/record';
 
+import promiseRecord from '../utils/promise-record';
 const badIdFormatAssertion = '`id` passed to `findRecord()` has to be non-empty string or number';
 const emberRun = emberRunLoop.backburner;
 
 const { ENV } = Ember;
 
 let globalClientIdCounter = 1;
 
-//Get the materialized model from the internalModel/promise that returns
-//an internal model and return it in a promiseObject. Useful for returning
-//from find methods
-function promiseRecord(internalModelPromise, label) {
-  let toReturn = internalModelPromise.then(internalModel => internalModel.getRecord());
-
-  return promiseObject(toReturn, label);
-}
-
 // Implementors Note:
 //
 //   The variables in this file are consistently named according to the following

packages/store/addon/-private/utils/promise-record.ts

@@ -0,0 +1,24 @@
+import InternalModel from '../system/model/internal-model';
+import { promiseObject } from '../system/promise-proxies';
+import { Record } from '../ts-interfaces/record';
+
+// shim type until we can properly type
+// these proxies
+export type PromiseProxy<T> = Promise<T>;
+
+/**
+ * Get the materialized model from the internalModel/promise
+ * that returns an internal model and return it in a promiseObject.
+ *
+ * Useful for returning from find methods
+ *
+ * @internal
+ */
+export default function promiseRecord(
+  internalModelPromise: Promise<InternalModel>,
+  label: string
+): PromiseProxy<Record> {
+  let toReturn = internalModelPromise.then(internalModel => internalModel.getRecord());
+
+  return promiseObject(toReturn, label);
+}