feat(test): add tests for src/browser/login

test/browser/pages/login.test.ts

+import { JSDOM } from "jsdom"
+import { LocationLike } from "../../unit/util.test"
+
+describe("login", () => {
+  describe("there is an element with id 'base'", () => {
+    beforeEach(() => {
+      const dom = new JSDOM()
+      global.document = dom.window.document
+
+      const location: LocationLike = {
+        pathname: "/healthz",
+        origin: "http://localhost:8080",
+      }
+
+      global.location = location as Location
+    })
+    afterEach(() => {
+      // Reset the global.document
+      global.document = undefined as any as Document
+      global.location = undefined as any as Location
+    })
+    it("should set the value to options.base", () => {
+      // Mock getElementById
+      const spy = jest.spyOn(document, "getElementById")
+      // Create a fake element and set the attribute
+      const mockElement = document.createElement("input")
+      mockElement.setAttribute("id", "base")
+      mockElement.setAttribute(
+        "data-settings",
+        '{"base":"./hello-world","csStaticBase":"./static/development/Users/jp/Dev/code-server","logLevel":2,"disableTelemetry":false,"disableUpdateCheck":false}',
+      )
+      document.body.appendChild(mockElement)
+      spy.mockImplementation(() => mockElement)
+      // Load file
+      require("../../../src/browser/pages/login")
+
+      const el: HTMLInputElement | null = document.querySelector("input#base")
+      expect(el?.value).toBe("/hello-world")
+    })
+  })
+
+  describe("there is no element with id 'base'", () => {
+    let initialDom: Document
+    beforeEach(() => {
+      const dom = new JSDOM()
+      initialDom = dom.window.document
+      global.document = dom.window.document
+
+      const location: LocationLike = {
+        pathname: "/healthz",
+        origin: "http://localhost:8080",
+      }
+
+      global.location = location as Location
+    })
+    afterEach(() => {
+      // Reset the global.document
+      global.document = undefined as any as Document
+      global.location = undefined as any as Location
+    })
+
+    it("should not change the DOM", () => {
+      // Load file
+      require("../../../src/browser/pages/login")
+      const currentDom = global.document
+      expect(initialDom).toBe(currentDom)
+    })
+  })
+})