1 files changed, 88 insertions, 0 deletions
diff --git a/packages/astro/test/astro-sync.test.js b/packages/astro/test/astro-sync.test.js
new file mode 100644
index 000000000..5f1fb2d14
--- /dev/null
+++ b/packages/astro/test/astro-sync.test.js
@@ -0,0 +1,88 @@
+import * as fs from 'node:fs';
+import { expect } from 'chai';
+import { loadFixture } from './test-utils.js';
+
+describe('astro sync', () => {
+	let fixture;
+	before(async () => {
+		fixture = await loadFixture({ root: './fixtures/content-collections/' });
+	});
+
+	it('Writes types to `.astro`', async () => {
+		let writtenFiles = {};
+		const fsMock = {
+			...fs,
+			promises: {
+				...fs.promises,
+				async writeFile(path, contents) {
+					writtenFiles[path] = contents;
+				},
+			},
+		};
+		await fixture.sync({ fs: fsMock });
+
+		const expectedTypesFile = new URL('.astro/types.d.ts', fixture.config.root).href;
+		expect(writtenFiles).to.haveOwnProperty(expectedTypesFile);
+		// smoke test `astro check` asserts whether content types pass.
+		expect(writtenFiles[expectedTypesFile]).to.include(
+			`declare module 'astro:content' {`,
+			'Types file does not include `astro:content` module declaration'
+		);
+	});
+
+	it('Adds type reference to `src/env.d.ts`', async () => {
+		let writtenFiles = {};
+		const typesEnvPath = new URL('env.d.ts', fixture.config.srcDir).href;
+		const fsMock = {
+			...fs,
+			existsSync(path, ...args) {
+				if (path.toString() === typesEnvPath) {
+					return true;
+				}
+				return fs.existsSync(path, ...args);
+			},
+			promises: {
+				...fs.promises,
+				async readFile(path, ...args) {
+					if (path.toString() === typesEnvPath) {
+						return `/// <reference path="astro/client" />`;
+					} else {
+						return fs.promises.readFile(path, ...args);
+					}
+				},
+				async writeFile(path, contents) {
+					writtenFiles[path] = contents;
+				},
+			},
+		};
+		await fixture.sync({ fs: fsMock });
+
+		expect(writtenFiles, 'Did not try to update env.d.ts file.').to.haveOwnProperty(typesEnvPath);
+		expect(writtenFiles[typesEnvPath]).to.include(`/// <reference path="../.astro/types.d.ts" />`);
+	});
+
+	it('Writes `src/env.d.ts` if none exists', async () => {
+		let writtenFiles = {};
+		const typesEnvPath = new URL('env.d.ts', fixture.config.srcDir).href;
+		const fsMock = {
+			...fs,
+			existsSync(path, ...args) {
+				if (path.toString() === typesEnvPath) {
+					return false;
+				}
+				return fs.existsSync(path, ...args);
+			},
+			promises: {
+				...fs.promises,
+				async writeFile(path, contents) {
+					writtenFiles[path] = contents;
+				},
+			},
+		};
+		await fixture.sync({ fs: fsMock });
+
+		expect(writtenFiles, 'Did not try to write env.d.ts file.').to.haveOwnProperty(typesEnvPath);
+		expect(writtenFiles[typesEnvPath]).to.include(`/// <reference types="astro/client" />`);
+		expect(writtenFiles[typesEnvPath]).to.include(`/// <reference path="../.astro/types.d.ts" />`);
+	});
+});