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Author: yaacovCR

src/__testUtils__/expectEqualPromisesOrValues.ts

@@ -8,9 +8,7 @@ import { expectMatchingValues } from './expectMatchingValues';
 export function expectEqualPromisesOrValues<T>(
   items: ReadonlyArray<PromiseOrValue<T>>,
 ): PromiseOrValue<T> {
-  const remainingItems = items.slice();
-  const firstItem = remainingItems.shift();
-
+  const [firstItem, ...remainingItems] = items;
   if (isPromise(firstItem)) {
     if (remainingItems.every(isPromise)) {
       return Promise.all(items).then(expectMatchingValues);

src/__testUtils__/expectMatchingValues.ts

@@ -1,9 +1,9 @@
 import { expectJSON } from './expectJSON';
 
 export function expectMatchingValues<T>(values: ReadonlyArray<T>): T {
-  const remainingValues = values.slice(1);
+  const [firstValue, ...remainingValues] = values;
   for (const value of remainingValues) {
-    expectJSON(value).toDeepEqual(values[0]);
+    expectJSON(value).toDeepEqual(firstValue);
   }
-  return values[0];
+  return firstValue;
 }