Strict null check files/test/electron-browser/utils.ts

Part of #60565

src/tsconfig.strictNullChecks.json

@@ -508,6 +508,7 @@
 		"./vs/workbench/services/files/node/watcher/common.ts",
 		"./vs/workbench/services/files/node/watcher/nsfw/watcher.ts",
 		"./vs/workbench/services/files/node/watcher/unix/watcher.ts",
+		"./vs/workbench/services/files/test/electron-browser/utils.ts",
 		"./vs/workbench/services/hash/common/hashService.ts",
 		"./vs/workbench/services/hash/node/hashService.ts",
 		"./vs/workbench/services/issue/common/issue.ts",

src/vs/workbench/services/files/test/electron-browser/utils.ts

@@ -5,7 +5,11 @@
 
 import { IFileStat } from 'vs/platform/files/common/files';
 
-export function getByName(root: IFileStat, name: string): IFileStat {
+export function getByName(root: IFileStat, name: string): IFileStat | null {
+	if (root.children === undefined) {
+		return null;
+	}
+
 	for (let i = 0; i < root.children.length; i++) {
 		if (root.children[i].name === name) {
 			return root.children[i];