fix(vitest): inline solid-js and its consumers in jsdom tests

.changeset/vitest-5-shared-server-projects.md

@@ -0,0 +1,5 @@
+---
+'vite-plugin-solid': patch
+---
+
+When the root config declares `test.projects` and leaves `test.sharedViteServer` unset, the plugin now sets it to `false` so every inline project resolves its own Vite config, as under Vitest 4. An explicit value is respected. Vitest 5 defaults the option to `true`, and a shared inline project takes its `test` options from the raw root block captured before any `config` hook runs, so it lost everything the plugin injects (the `jsdom` default, the `@testing-library/jest-dom` setup file, `server.deps`). Ports solidjs/solid-vite-plugin#370; refs #369.

.changeset/vitest-client-inline-runtime.md

@@ -0,0 +1,5 @@
+---
+'vite-plugin-solid': patch
+---
+
+In Vitest DOM tests (the jsdom default, no `ssr` option), the plugin now inlines `solid-js` and the packages that import it without a `solid` export condition, such as `@solidjs/testing-library`. Before, they stayed external, and the host runtime resolved their own imports. Node gets the `browser` condition from Vitest's worker `--conditions`, but Deno does not apply it in worker threads and resolves `deno`/`node`. Under Deno, `@solidjs/testing-library` loaded the server build of `solid-js/web` and `render` threw "Client-only API called on the server side" (solidjs/solid-vite-plugin#369). Inlining sends these imports through Vite's `browser` condition and loads one client-build instance. A `test.server.deps.inline` list is merged with the plugin's, and a `test.server.deps.external` entry for `solid-js` still opts out. With `ssr: true`, tests keep `solid-js` external as before.

.github/workflows/vitest.yml

@@ -34,3 +34,7 @@ jobs:
       - name: Run tests
         working-directory: examples/vite-6
         run: pnpm run test
+
+      - name: Run jsdom tests
+        working-directory: examples/vite-6
+        run: pnpm run test:jsdom

examples/vite-6/package.json

@@ -7,13 +7,15 @@
     "build": "vite build",
     "preview": "vite preview",
     "test": "vitest --browser.headless --run",
-    "test-dev": "vitest"
+    "test-dev": "vitest",
+    "test:jsdom": "NODE_OPTIONS=--import=./tests/deno-conditions.mjs vitest --run --config vitest.jsdom.config.ts --pool=forks"
   },
   "devDependencies": {
     "@solidjs/testing-library": "^0.8.10",
     "@testing-library/jest-dom": "^6.6.3",
     "@testing-library/user-event": "^14.6.1",
     "@vitest/browser": "^3.0.7",
+    "jsdom": "^26.0.0",
     "playwright": "^1.50.1",
     "vite": "^6.2.0",
     "vite-plugin-solid": "workspace:*",

examples/vite-6/tests/deno-conditions.mjs

@@ -0,0 +1,29 @@
+// Preloaded into the vitest workers (NODE_OPTIONS=--import) by `test:jsdom`.
+// It makes Node resolve bare imports the way Deno does in a worker thread.
+// Deno does not apply the `browser` condition that vitest passes to the
+// workers as `--conditions`, so an externalized package's own
+// `import "solid-js/web"` resolves `deno`/`node`, which is the server build
+// (solidjs/solid-vite-plugin#369).
+import module from 'node:module';
+
+const denoConditions = (context) => ({
+  ...context,
+  conditions: [...context.conditions.filter((c) => c !== 'browser'), 'deno'],
+});
+
+if (module.registerHooks) {
+  module.registerHooks({
+    resolve: (specifier, context, next) => next(specifier, denoConditions(context)),
+  });
+} else {
+  // Node < 22.15 has only the async loader API.
+  module.register(
+    'data:text/javascript,' +
+      encodeURIComponent(`
+        export async function resolve(specifier, context, next) {
+          const conditions = context.conditions.filter((c) => c !== 'browser');
+          return next(specifier, { ...context, conditions: [...conditions, 'deno'] });
+        }
+      `),
+  );
+}

examples/vite-6/tests/jsdom/testing-library.test.tsx

@@ -0,0 +1,33 @@
+// jsdom regression test for solidjs/solid-vite-plugin#369, run by
+// `pnpm test:jsdom` with tests/deno-conditions.mjs preloaded.
+// `@solidjs/testing-library` has no `solid` export condition. Left external,
+// its own `import "solid-js/web"` is resolved by the host runtime, and under
+// Deno that is the server build, so `render` threw "Client-only API called
+// on the server side". The plugin inlines it with solid-js, so its imports
+// go through Vite's `browser` condition and share the test file's instance.
+import { render } from '@solidjs/testing-library';
+import { createSignal } from 'solid-js';
+import { isServer } from 'solid-js/web';
+import { expect, test } from 'vitest';
+
+function Counter() {
+  const [count, setCount] = createSignal(0);
+  return (
+    <button type="button" onClick={() => setCount(count() + 1)}>
+      count: {count()}
+    </button>
+  );
+}
+
+test('resolves the browser build in the test file', () => {
+  expect(isServer).toBe(false);
+});
+
+test('renders and updates through @solidjs/testing-library', () => {
+  const { getByRole, unmount } = render(() => <Counter />);
+  const button = getByRole('button');
+  expect(button.textContent).toBe('count: 0');
+  button.click();
+  expect(button.textContent).toBe('count: 1');
+  unmount();
+});

examples/vite-6/vitest.config.ts

@@ -1,4 +1,4 @@
-import { defineConfig } from 'vitest/config';
+import { configDefaults, defineConfig } from 'vitest/config';
 import solidPlugin from '../../src/index.js';
 
 export default defineConfig({
@@ -8,6 +8,8 @@ export default defineConfig({
   },
   test: {
     environment: 'node',
+    // tests/jsdom runs under vitest.jsdom.config.ts (`pnpm test:jsdom`).
+    exclude: [...configDefaults.exclude, 'tests/jsdom/**'],
     browser: {
       enabled: true,
       provider: 'playwright',

examples/vite-6/vitest.jsdom.config.ts

@@ -0,0 +1,12 @@
+import { defineConfig } from 'vitest/config';
+import solidPlugin from '../../src/index.js';
+
+// jsdom suite (`pnpm test:jsdom`). The default vitest.config.ts runs the
+// browser-mode suite and excludes tests/jsdom.
+export default defineConfig({
+  plugins: [solidPlugin()],
+  test: {
+    environment: 'jsdom',
+    include: ['tests/jsdom/**/*.test.tsx'],
+  },
+});