Improve desktop coverage (#33462)

* Improve desktop coverage

* Silence vitest warning

* Improve coverage

* Whoops

apps/desktop/src/build-config.test.ts

@@ -0,0 +1,35 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+import { expect, describe, it, beforeEach, vi } from "vitest";
+import { fs as memfs, vol } from "memfs";
+
+import { getBuildConfig } from "./build-config.js";
+
+vi.mock("node:fs", () => ({ default: memfs }));
+
+beforeEach(() => {
+    // Reset the state of the in-memory fs
+    vol.reset();
+});
+
+describe("getBuildConfig", () => {
+    it("should read fields from package.json correctly", () => {
+        vol.fromJSON({
+            "package.json": JSON.stringify({
+                electron_appId: "app.id",
+                electron_protocol: "proto",
+                electron_windows_cert_sn: "subject.name",
+            }),
+        });
+
+        const config = getBuildConfig();
+        expect(config.appId).toBe("app.id");
+        expect(config.protocol).toBe("proto");
+        expect(config.windowsCertSubjectName).toBe("subject.name");
+    });
+});

apps/desktop/src/icon.test.ts

@@ -0,0 +1,44 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+import { expect, describe, it, beforeEach, vi } from "vitest";
+import { fs as memfs, vol } from "memfs";
+import path from "node:path";
+
+import { getIconPath } from "./icon.js";
+
+vi.mock("node:fs/promises", () => ({ default: memfs.promises }));
+
+beforeEach(() => {
+    // Reset the state of the in-memory fs
+    vol.reset();
+});
+
+describe("getIconPath", () => {
+    beforeEach(() => {
+        vol.fromJSON(
+            {
+                "build/icon.png": "png",
+                "build/icon.ico": "ico",
+            },
+            "../webapp",
+        );
+    });
+
+    it("should use .ico on Windows", async () => {
+        vi.spyOn(process, "platform", "get").mockReturnValue("win32");
+        await expect(getIconPath()).resolves.toEqual(path.resolve("../build/icon.ico"));
+    });
+    it("should use .png on macOS", async () => {
+        vi.spyOn(process, "platform", "get").mockReturnValue("darwin");
+        await expect(getIconPath()).resolves.toEqual(path.resolve("../build/icon.png"));
+    });
+    it("should use .png on Linux", async () => {
+        vi.spyOn(process, "platform", "get").mockReturnValue("linux");
+        await expect(getIconPath()).resolves.toEqual(path.resolve("../build/icon.png"));
+    });
+});

apps/desktop/src/utils.test.ts

@@ -0,0 +1,78 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+import { expect, describe, it, beforeEach, vi } from "vitest";
+import { fs as memfs, vol } from "memfs";
+
+import { loadJsonFile, tryPaths, randomArray } from "./utils.js";
+
+vi.mock("node:fs", () => ({ default: memfs }));
+vi.mock("node:fs/promises", () => ({ default: memfs.promises }));
+
+beforeEach(() => {
+    // Reset the state of the in-memory fs
+    vol.reset();
+});
+
+describe("randomArray", () => {
+    it("should return an array matching the requested size", async () => {
+        function toUnpaddedBase64Size(size: number): number {
+            return Math.ceil((4 * size) / 3);
+        }
+
+        await expect(randomArray(100)).resolves.toHaveLength(toUnpaddedBase64Size(100));
+        await expect(randomArray(32)).resolves.toHaveLength(toUnpaddedBase64Size(32));
+    });
+
+    it("should return a unique random array", async () => {
+        const arr1 = await randomArray(60);
+        const arr2 = await randomArray(60);
+        expect(arr1).not.toEqual(arr2);
+    });
+});
+
+describe("loadJsonFile", () => {
+    beforeEach(() => {
+        vol.fromJSON({
+            "./file.json": JSON.stringify({ file1: true }),
+            "./nested/deep/file.json": JSON.stringify({ file2: true }),
+        });
+    });
+
+    it("should load and parse a JSON file correctly", () => {
+        expect(loadJsonFile("file.json")).toStrictEqual({ file1: true });
+    });
+
+    it("should use args as path segments", () => {
+        expect(loadJsonFile("nested", "deep", "file.json")).toStrictEqual({ file2: true });
+    });
+
+    it("should return an empty object when file does not exist", () => {
+        expect(loadJsonFile("unknown-file.json")).toStrictEqual({});
+    });
+});
+
+describe("tryPaths", () => {
+    beforeEach(() => {
+        vol.fromNestedJSON({
+            "./dirA/": {},
+            "./dir/dirB/": {},
+        });
+    });
+
+    it("should find file relative to given root", async () => {
+        await expect(tryPaths("name", "dir", ["dirB"])).resolves.toEqual("dir/dirB/");
+    });
+
+    it("should handle unknown paths", async () => {
+        await expect(tryPaths("name", ".", ["dirB", "dirA"])).resolves.toEqual("dirA/");
+    });
+
+    it("should throw error if file does not exist", async () => {
+        await expect(tryPaths("name", "dir", ["a.json", "b.json"])).rejects.toThrow("Failed to find name path");
+    });
+});

apps/desktop/src/utils.ts

@@ -10,6 +10,10 @@ import fs from "node:fs";
 import path from "node:path";
 import afs from "node:fs/promises";
 
+/**
+ * Returns a random array of a specified size in unpadded base64
+ * @param size - the size of the underlying random array
+ */
 export async function randomArray(size: number): Promise<string> {
     return new Promise((resolve, reject) => {
         crypto.randomBytes(size, (err, buf) => {
@@ -62,9 +66,9 @@ export async function tryPaths(name: string, root: string, rawPaths: string[]):
             return p + "/";
         } catch {}
     }
-    console.log(`Couldn't find ${name} files in any of: `);
+    console.log(`Couldn't find '${name}' in any of: `);
     for (const p of paths) {
         console.log("\t" + path.resolve(p));
     }
-    throw new Error(`Failed to find ${name} files`);
+    throw new Error(`Failed to find ${name} path`);
 }

packages/vite-common/vite.config.ts

@@ -6,7 +6,7 @@ Please see LICENSE files in the repository root for full details.
 */
 
 import { defineConfig, type ViteUserConfig } from "vitest/config";
-import { type Reporter } from "vitest/reporters";
+import { type Reporter } from "vitest/node";
 import { env } from "node:process";
 
 const reporters: NonNullable<ViteUserConfig["test"]>["reporters"] = [["default"]];