fix(snapshot-utils): snapshot header regexp to work with newline across OSes (#15803)

Author: hainenber

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## main
 
+### Fixes
+
+- `[jest-snapshot-utils]` Correct snapshot header regexp to work with newline across OSes ([#15803](https://github.com/jestjs/jest/pull/15803))
+
 ## 30.1.1
 
 ### Fixes

packages/jest-snapshot-utils/src/utils.ts

@@ -13,7 +13,7 @@ import type {Config} from '@jest/types';
 import type {SnapshotData} from './types';
 
 export const SNAPSHOT_VERSION = '1';
-const SNAPSHOT_HEADER_REGEXP = /^\/\/ Jest Snapshot v(.+), (.+)\r?\n/;
+const SNAPSHOT_HEADER_REGEXP = /^\/\/ Jest Snapshot v(.+), (.+)$/m;
 export const SNAPSHOT_GUIDE_LINK = 'https://jestjs.io/docs/snapshot-testing';
 export const SNAPSHOT_VERSION_WARNING = chalk.yellow(
   `${chalk.bold('Warning')}: Before you upgrade snapshots, ` +