fix: nitroV2Plugin compress public assets by default

fixes #2096
- match `1.x` behavior for easier migration; can still be overridden to false for users who prefer uncompressed files.
- extract common build test utilities.
- fix tree shaking tests that were using unreliable regex (didn't account for minification and variable renaming); replace with a unique string identifier for better resilience, and add a complementary test for the tree shaking with side effects case.
- add vitest `~` alias configuration, as the solid plugin wasn't resolving it in the test environment.

Author: yinonburgansky

apps/tests/src/build/compressed-public-assets.server.test.ts

@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+import { getBuildOutputDirs, getFiles } from "~/utils/build-output-utils";
+
+describe("public assets compression", () => {
+  it("includes at least one .gz and one .br file in client output", async () => {
+    const { clientOutputRoot } = getBuildOutputDirs();
+    const gzFiles = await getFiles(clientOutputRoot, /\.gz$/);
+    const brFiles = await getFiles(clientOutputRoot, /\.br$/);
+
+    // Only files above 1KB are compressed, so we check that at least one .gz and one .br file exists
+    expect(
+      gzFiles.length,
+      `No .gz files found in client output: ${clientOutputRoot}`,
+    ).toBeGreaterThan(0);
+    expect(
+      brFiles.length,
+      `No .br files found in client output: ${clientOutputRoot}`,
+    ).toBeGreaterThan(0);
+  });
+});

apps/tests/src/routes/treeshaking/(no-side-effects).tsx

@@ -1,6 +1,6 @@
 import { createAsync } from "@solidjs/router";
 
-const a = 1;
+const a = "myTreeshakingTestUniqueString1";
 
 function getA() {
   return a;

apps/tests/src/routes/treeshaking/server-secret-leak.server.test.ts

@@ -1,30 +1,13 @@
-import { existsSync } from "node:fs";
-import { readdir, readFile } from "node:fs/promises";
-import path from "node:path";
-import { brotliDecompressSync, gunzipSync } from "node:zlib";
 import { describe, expect, it } from "vitest";
+import { getBuildOutputDirs, getFiles, readFileContent } from "~/utils/build-output-utils";
 
 // Avoid full pattern to exclude this file from scan
 const SECRET_MARKER = new RegExp(`${"MyServer"}${"SuperSecretUniqueString"}\\d+`, "g");
 const ALL_FILE_EXTENSIONS = /\.(ts|tsx|js|jsx|mjs|cjs|mts|cts|css|map|gz|br)$/;
 
 describe("server code does not leak to client bundle", () => {
   it("verifies secret markers are server-only and not in client output", async () => {
-    const appRoot = process.cwd();
-    const sourceRoot = path.join(appRoot, "src");
-    const serverOutputRoot = path.join(appRoot, ".output/server");
-    const clientOutputRoot = path.join(appRoot, ".output/public");
-
-    // Verify required directories exist
-    expect(existsSync(sourceRoot), `Source dir not found: ${sourceRoot}`).toBe(true);
-    expect(
-      existsSync(serverOutputRoot),
-      `Server output dir not found: ${serverOutputRoot}. Did you run the build? (pnpm --filter tests run build)`,
-    ).toBe(true);
-    expect(
-      existsSync(clientOutputRoot),
-      `Client output dir not found: ${clientOutputRoot}. Did you run the build? (pnpm --filter tests run build)`,
-    ).toBe(true);
+    const { sourceRoot, serverOutputRoot, clientOutputRoot } = getBuildOutputDirs();
 
     // Collect and validate markers from source code
     const sourceMarkerCounts = await countSourceMarkers(sourceRoot);
@@ -77,22 +60,3 @@ async function countSourceMarkers(rootDir: string) {
   }
   return markerCounts;
 }
-
-async function getFiles(dir: string, fileRegex: RegExp): Promise<string[]> {
-  const entries = await readdir(dir, { recursive: true, withFileTypes: true });
-  return entries
-    .filter(e => e.isFile() && fileRegex.test(e.name))
-    .map(e => path.join(e.parentPath, e.name));
-}
-
-async function readFileContent(filePath: string) {
-  if (filePath.endsWith(".br")) {
-    return brotliDecompressSync(await readFile(filePath)).toString("utf-8");
-  }
-
-  if (filePath.endsWith(".gz")) {
-    return gunzipSync(await readFile(filePath)).toString("utf-8");
-  }
-
-  return readFile(filePath, "utf-8");
-}

apps/tests/src/routes/treeshaking/side-effects.tsx

@@ -1,6 +1,6 @@
 import { createAsync } from "@solidjs/router";
 
-export const a = 1;
+export const a = "myTreeshakingTestUniqueString2";
 
 function getA() {
   return a;

apps/tests/src/routes/treeshaking/treeshake.server.test.ts

@@ -1,23 +1,30 @@
-// I'm not sure if it's fair calling this a unit test, but let's go with that
-import { readdir, readFile } from "node:fs/promises";
-import path from "node:path";
 import { describe, expect, it } from "vitest";
+import { getBuildOutputDirs, getFiles, readFileContent } from "~/utils/build-output-utils";
 
 describe("Make sure treeshaking works", () => {
   it("should not have any unused code in the client-bundle", async () => {
-    const buildDir = path.resolve(process.cwd(), ".output/public/_build/assets");
-    const files = await readdir(buildDir);
-    const targetFile = files.find(
-      file => file.startsWith("(no-side-effects)-") && file.endsWith(".js"),
-    );
-    if (!targetFile) {
-      throw new Error("Treeshaking test: No target file not found");
+    const { clientOutputRoot } = getBuildOutputDirs();
+    const files = await getFiles(clientOutputRoot, /^\(no-side-effects\)-.*\.js(\.gz|\.br)?$/);
+
+    expect(files.length, "No files matching the treeshaking pattern found").toBeGreaterThan(0);
+
+    for (const targetFile of files) {
+      const file = await readFileContent(targetFile);
+      const result = file.includes("myTreeshakingTestUniqueString1");
+      expect(result, `Unused code found in file: ${targetFile}`).toBeFalsy();
     }
-    const file = await readFile(path.join(buildDir, targetFile), "utf-8");
+  });
 
-    const regex = /const a = 1;/g;
-    const result = regex.test(file);
+  it("should include side-effects code in the client-bundle", async () => {
+    const { clientOutputRoot } = getBuildOutputDirs();
+    const files = await getFiles(clientOutputRoot, /^side-effects.*\.js(\.gz|\.br)?$/);
 
-    expect(result).toBeFalsy();
+    expect(files.length, "No side-effects files matching the pattern found").toBeGreaterThan(0);
+
+    for (const targetFile of files) {
+      const file = await readFileContent(targetFile);
+      const result = file.includes("myTreeshakingTestUniqueString2");
+      expect(result, `Side-effects code not found in file: ${targetFile}`).toBeTruthy();
+    }
   });
 });

apps/tests/src/utils/build-output-utils.ts

@@ -0,0 +1,53 @@
+import { existsSync } from "node:fs";
+import { readFile, readdir } from "node:fs/promises";
+import path from "node:path";
+import { brotliDecompressSync, gunzipSync } from "node:zlib";
+
+export function getBuildOutputDirs() {
+  const appRoot = process.cwd();
+  const sourceRoot = path.join(appRoot, "src");
+  const serverOutputRoot = path.join(appRoot, ".output/server");
+  const clientOutputRoot = path.join(appRoot, ".output/public");
+
+  if (!existsSync(sourceRoot)) {
+    throw new Error(`Source dir not found: ${sourceRoot}`);
+  }
+
+  if (!existsSync(serverOutputRoot)) {
+    throw new Error(
+      `Server output dir not found: ${serverOutputRoot}. Did you run the build? (pnpm --filter tests run build)`,
+    );
+  }
+
+  if (!existsSync(clientOutputRoot)) {
+    throw new Error(
+      `Client output dir not found: ${clientOutputRoot}. Did you run the build? (pnpm --filter tests run build)`,
+    );
+  }
+
+  return {
+    sourceRoot,
+    serverOutputRoot,
+    clientOutputRoot,
+  };
+}
+
+export async function getFiles(dir: string, fileRegex: RegExp): Promise<string[]> {
+  const entries = await readdir(dir, { recursive: true, withFileTypes: true });
+
+  return entries
+    .filter(e => e.isFile() && fileRegex.test(e.name))
+    .map(e => path.join(e.parentPath, e.name));
+}
+
+export async function readFileContent(filePath: string) {
+  if (filePath.endsWith(".br")) {
+    return brotliDecompressSync(await readFile(filePath)).toString("utf-8");
+  }
+
+  if (filePath.endsWith(".gz")) {
+    return gunzipSync(await readFile(filePath)).toString("utf-8");
+  }
+
+  return readFile(filePath, "utf-8");
+}

apps/tests/vitest.config.ts

@@ -1,8 +1,14 @@
 import solid from "vite-plugin-solid";
 import { defineConfig } from "vitest/config";
 import { playwright } from "@vitest/browser-playwright";
+import path from "path";
 
 export default defineConfig({
+  resolve: {
+    alias: {
+      "~": path.resolve(__dirname, "./src"),
+    },
+  },
   plugins: [solid()],
   test: {
     mockReset: true,

packages/start-nitro-v2-vite-plugin/src/index.ts

@@ -82,6 +82,7 @@ export function nitroV2Plugin(nitroConfig?: UserNitroConfig): PluginOption {
                   generateTsConfig: false,
                   generateRuntimeConfigTypes: false,
                 },
+                compressPublicAssets: true,
                 ...nitroConfig,
                 dev: false,
                 routeRules: {