vercel__workflow/packages/sveltekit/src/plugin.test.ts

import { mkdir, mkdtemp, rm, writeFile } from 'node:fs/promises';
import { tmpdir } from 'node:os';
import { join } from 'node:path';
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';

const mocks = vi.hoisted(() => ({
  build: vi.fn<() => Promise<void>>(),
  builderConfigs: [] as Array<Record<string, unknown>>,
  loadConfig: vi.fn(),
}));

vi.mock('@sveltejs/load-config', () => ({
  loadConfig: mocks.loadConfig,
}));

vi.mock('@workflow/builders', () => ({
  createBuildQueue: () => (fn: () => Promise<void>) => fn(),
}));

vi.mock('@workflow/rollup', () => ({
  workflowTransformPlugin: () => ({ name: 'workflow:transform' }),
}));

vi.mock('@workflow/vite', () => ({
  workflowHotUpdatePlugin: () => ({ name: 'workflow:hot-update' }),
}));

vi.mock('./builder.js', () => ({
  SvelteKitBuilder: class {
    constructor(config: Record<string, unknown>) {
      mocks.builderConfigs.push(config);
    }

    build = mocks.build;
  },
}));

import { workflowPlugin } from './plugin.js';

const originalWorkingDir = process.cwd();
let workingDir: string;

beforeEach(async () => {
  workingDir = await mkdtemp(join(tmpdir(), 'workflow-sveltekit-'));
  process.chdir(workingDir);
  workingDir = process.cwd(); // MacOS: resolves symlink of generated /var/folders/... through to /private/var/folders/...
  mocks.build.mockResolvedValue(undefined);
});

afterEach(async () => {
  process.chdir(originalWorkingDir);
  await rm(workingDir, { force: true, recursive: true });
  vi.clearAllMocks();
  mocks.builderConfigs.length = 0;
});

describe('workflowPlugin', () => {
  it('loads svelte.config.js directly and uses the default routes directory', async () => {
    const configPath = join(workingDir, 'svelte.config.js');
    await writeFile(configPath, 'export default {};');
    mocks.loadConfig.mockResolvedValue({
      config: {},
      configFilePath: configPath,
      configSource: 'svelte',
    });

    const [plugins] = workflowPlugin();
    await plugins;

    expect(mocks.loadConfig).toHaveBeenCalledWith(configPath, {
      traverse: false,
    });
    expect(mocks.builderConfigs).toEqual([
      { routesDir: join(workingDir, 'src/routes'), workingDir },
    ]);
    expect(mocks.build).toHaveBeenCalledOnce();
  });

  it('loads routes from the SvelteKit Vite plugin without recursing', async () => {
    const routesDir = join(workingDir, 'app/routes');
    let nestedPlugins: ReturnType<typeof workflowPlugin> | undefined;
    mocks.loadConfig.mockImplementation(async () => {
      nestedPlugins = workflowPlugin();
      return {
        config: { kit: { files: { routes: routesDir } } },
        configFilePath: join(workingDir, 'vite.config.ts'),
        configSource: 'vite',
      };
    });

    const [plugins] = workflowPlugin();
    await plugins;

    expect(nestedPlugins).toEqual([]);
    expect(mocks.loadConfig).toHaveBeenCalledWith(workingDir, {
      traverse: false,
    });
    expect(mocks.builderConfigs).toEqual([{ routesDir, workingDir }]);
    expect(mocks.build).toHaveBeenCalledOnce();
  });

  it('reuses routes generated by another Vite config context', async () => {
    const routesDir = join(workingDir, 'app/routes');
    await mkdir(join(workingDir, 'node_modules/.cache/workflow'), {
      recursive: true,
    });
    await mkdir(join(routesDir, '.well-known/workflow/v1/flow'), {
      recursive: true,
    });
    await writeFile(
      join(workingDir, 'node_modules/.cache/workflow/sveltekit-build.json'),
      JSON.stringify({ pid: process.pid, routesDir })
    );
    await writeFile(
      join(routesDir, '.well-known/workflow/v1/flow/+server.js'),
      ''
    );

    const [plugins] = workflowPlugin();
    await plugins;

    expect(mocks.loadConfig).not.toHaveBeenCalled();
    expect(mocks.builderConfigs).toEqual([{ routesDir, workingDir }]);
    expect(mocks.build).not.toHaveBeenCalled();
  });

  it('passes source map options to the builder', async () => {
    const configPath = join(workingDir, 'svelte.config.js');
    await writeFile(configPath, 'export default {};');
    mocks.loadConfig.mockResolvedValue({
      config: {},
      configFilePath: configPath,
      configSource: 'svelte',
    });

    const [plugins] = workflowPlugin({ sourcemap: 'external' });
    await plugins;

    expect(mocks.builderConfigs).toEqual([
      {
        routesDir: join(workingDir, 'src/routes'),
        workingDir,
        sourcemap: 'external',
      },
    ]);
  });
});