chore(global-header): migrate to Jest 30 (#3012)

Install Jest 30 peer dependencies as required by @backstage/cli 0.36.0 and fix test incompatibilities for Jest 30 and JSDOM 27.

Signed-off-by: Jon Koops <jonkoops@gmail.com>

Author: jonkoops

workspaces/global-header/package.json

@@ -50,7 +50,12 @@
     "@backstage/e2e-test-utils": "^0.1.2",
     "@backstage/repo-tools": "^0.17.0",
     "@changesets/cli": "^2.27.1",
+    "@jest/environment-jsdom-abstract": "^30.3.0",
     "@playwright/test": "1.58.2",
+    "@types/jest": "^30.0.0",
+    "@types/jsdom": "^27.0.0",
+    "jest": "^30.3.0",
+    "jsdom": "^27.1.0",
     "knip": "^5.27.4",
     "node-gyp": "^9.0.0",
     "prettier": "^2.3.2",

workspaces/global-header/packages/app-legacy/jest.setup.js

@@ -0,0 +1,23 @@
+/*
+ * Copyright Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Node 25+ removed SlowBuffer from the buffer module.
+// Transitive deps (buffer-equal-constant-time via jsonwebtoken) still reference it.
+const bufferModule = require('node:buffer');
+
+if (!bufferModule.SlowBuffer) {
+  bufferModule.SlowBuffer = bufferModule.Buffer;
+}

workspaces/global-header/packages/app-legacy/package.json

@@ -11,6 +11,11 @@
   "backstage": {
     "role": "frontend"
   },
+  "jest": {
+    "setupFiles": [
+      "<rootDir>/../jest.setup.js"
+    ]
+  },
   "scripts": {
     "start": "backstage-cli package start",
     "build": "backstage-cli package build",

workspaces/global-header/packages/app/jest.setup.js

@@ -0,0 +1,23 @@
+/*
+ * Copyright Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Node 25+ removed SlowBuffer from the buffer module.
+// Transitive deps (buffer-equal-constant-time via jsonwebtoken) still reference it.
+const bufferModule = require('node:buffer');
+
+if (!bufferModule.SlowBuffer) {
+  bufferModule.SlowBuffer = bufferModule.Buffer;
+}

workspaces/global-header/packages/app/package.json

@@ -11,6 +11,11 @@
   "backstage": {
     "role": "frontend"
   },
+  "jest": {
+    "setupFiles": [
+      "<rootDir>/../jest.setup.js"
+    ]
+  },
   "scripts": {
     "start": "backstage-cli package start",
     "build": "backstage-cli package build",

workspaces/global-header/plugins/global-header/src/components/HeaderDropdownComponent/HelpDropdown.test.tsx

@@ -297,7 +297,7 @@ describe('HelpDropdown', () => {
 
     const button = screen.getByRole('button');
     expect(button).toHaveStyle('margin-left: 16px');
-    expect(button).toHaveStyle('color: red');
+    expect(button).toHaveStyle('color: rgb(255, 0, 0)');
   });
 
   it('processes mount point configurations correctly', async () => {