feat: add cache headers to assets in Vercel adapter (#7729)

* feat: cache assets in Vercel adapter

* Update tidy-tips-doubt.md

* chore: update lockfile

* Update packages/integrations/vercel/test/static-assets.test.js

* Update packages/integrations/vercel/test/static-assets.test.js

* Update packages/integrations/vercel/test/static-assets.test.js

* chore: update split test

---------

Co-authored-by: Kid <44045911+kidonng@users.noreply.github.com>
Co-authored-by: Nate Moore <nate@astro.build>
Co-authored-by: Nate Moore <natemoo-re@users.noreply.github.com>

1 files changed, 84 insertions, 0 deletions

diff --git a/packages/integrations/vercel/test/static-assets.test.js b/packages/integrations/vercel/test/static-assets.test.js
new file mode 100644
index 000000000..b2bb4542f
--- /dev/null
+++ b/packages/integrations/vercel/test/static-assets.test.js
@@ -0,0 +1,84 @@
+import { expect } from 'chai';
+import { loadFixture } from './test-utils.js';
+
+describe('Static Assets', () => {
+	/** @type {import('../../../astro/test/test-utils.js').Fixture} */
+	let fixture;
+
+	const VALID_CACHE_CONTROL = 'public, max-age=31536000, immutable';
+
+	async function build({ adapter, assets }) {
+		fixture = await loadFixture({
+			root: './fixtures/static-assets/',
+			adapter,
+			build: {
+				assets,
+			}
+		});
+		await fixture.build();
+	}
+
+	async function getConfig() {
+		const json = await fixture.readFile('../.vercel/output/config.json');
+		const config = JSON.parse(json);
+
+		return config;
+	}
+
+	async function getAssets() {
+		return fixture.config.build.assets;
+	}
+
+	async function checkValidCacheControl(assets) {
+		const config = await getConfig();
+
+		const route = config.routes.find((r) => r.src === `^/${assets ?? getAssets()}/(.*)$`);
+		expect(route.headers['cache-control']).to.equal(VALID_CACHE_CONTROL);
+		expect(route.continue).to.equal(true);
+	}
+
+	describe('static adapter', async () => {
+		const adapter = await import('@astrojs/vercel/static');
+
+		it('has cache control', async () => {
+			await build({ adapter });
+			checkValidCacheControl();
+		});
+
+		it('has cache control other assets', async () => {
+			const assets = '_foo';
+			await build({ adapter, assets });
+			checkValidCacheControl(assets);
+		});
+	});
+
+	describe('serverless adapter', async () => {
+		const adapter = await import('@astrojs/vercel/serverless');
+
+		it('has cache control', async () => {
+			await build({ adapter });
+			checkValidCacheControl();
+		});
+
+		it('has cache control other assets', async () => {
+			const assets = '_foo';
+			await build({ adapter, assets });
+			checkValidCacheControl(assets);
+		});
+	});
+
+	describe('edge adapter', async () => {
+		const adapter = await import('@astrojs/vercel/edge');
+
+		it('has cache control', async () => {
+			await build({ adapter });
+			checkValidCacheControl();
+		});
+
+		it('has cache control other assets', async () => {
+			const assets = '_foo';
+			await build({ adapter, assets });
+			checkValidCacheControl(assets);
+		});
+	});
+});