fix(remix-dev/vite): bundle CSS from client entry

.changeset/brown-hotels-rush.md

@@ -0,0 +1,5 @@
+---
+"@remix-run/dev": patch
+---
+
+Bundle CSS imported in client entry file in Vite plugin

integration/vite-css-build-test.ts

@@ -50,6 +50,22 @@ test.describe("Vite CSS build", () => {
             ],
           });
         `,
+        "app/entry.client.tsx": js`
+          import "./entry.client.css";
+
+          import { RemixBrowser } from "@remix-run/react";
+          import { startTransition, StrictMode } from "react";
+          import { hydrateRoot } from "react-dom/client";
+
+          startTransition(() => {
+            hydrateRoot(
+              document,
+              <StrictMode>
+                <RemixBrowser />
+              </StrictMode>
+            );
+          });
+        `,
         "app/root.tsx": js`
           import { Links, Meta, Outlet, Scripts } from "@remix-run/react";
 
@@ -70,6 +86,12 @@ test.describe("Vite CSS build", () => {
             );
           }
         `,
+        "app/entry.client.css": css`
+          .client-entry {
+            background: pink;
+            padding: ${TEST_PADDING_VALUE};
+          }
+        `,
         "app/routes/_index/styles-bundled.css": css`
           .index_bundled {
             background: papayawhip;
@@ -118,12 +140,14 @@ test.describe("Vite CSS build", () => {
           export default function IndexRoute() {
             return (
               <div id="index">
-                <div data-css-modules className={cssModulesStyles.index}>
-                  <div data-css-linked className="index_linked">
-                    <div data-css-bundled className="index_bundled">
-                      <div data-css-vanilla-global className="index_vanilla_global">
-                        <div data-css-vanilla-local className={stylesVanillaLocal.index}>
-                          <h2>CSS test</h2>
+                <div data-client-entry className="client-entry">
+                  <div data-css-modules className={cssModulesStyles.index}>
+                    <div data-css-linked className="index_linked">
+                      <div data-css-bundled className="index_bundled">
+                        <div data-css-vanilla-global className="index_vanilla_global">
+                          <div data-css-vanilla-local className={stylesVanillaLocal.index}>
+                            <h2>CSS test</h2>
+                          </div>
                         </div>
                       </div>
                     </div>
@@ -146,6 +170,10 @@ test.describe("Vite CSS build", () => {
   test("renders styles", async ({ page }) => {
     let app = new PlaywrightFixture(appFixture, page);
     await app.goto("/");
+    await expect(page.locator("#index [data-client-entry]")).toHaveCSS(
+      "padding",
+      TEST_PADDING_VALUE
+    );
     await expect(page.locator("#index [data-css-modules]")).toHaveCSS(
       "padding",
       TEST_PADDING_VALUE

integration/vite-css-dev-test.ts

@@ -43,6 +43,22 @@ test.describe("Vite CSS dev", () => {
             ],
           });
         `,
+        "app/entry.client.tsx": js`
+          import "./entry.client.css";
+
+          import { RemixBrowser } from "@remix-run/react";
+          import { startTransition, StrictMode } from "react";
+          import { hydrateRoot } from "react-dom/client";
+
+          startTransition(() => {
+            hydrateRoot(
+              document,
+              <StrictMode>
+                <RemixBrowser />
+              </StrictMode>
+            );
+          });
+        `,
         "app/root.tsx": js`
           import { Links, Meta, Outlet, Scripts, LiveReload } from "@remix-run/react";
 
@@ -64,6 +80,12 @@ test.describe("Vite CSS dev", () => {
             );
           }
         `,
+        "app/entry.client.css": css`
+          .client-entry {
+            background: pink;
+            padding: ${TEST_PADDING_VALUE};
+          }
+        `,
         "app/styles-bundled.css": css`
           .index_bundled {
             background: papayawhip;
@@ -113,12 +135,14 @@ test.describe("Vite CSS dev", () => {
             return (
               <div id="index">
                 <input />
-                <div data-css-modules className={cssModulesStyles.index}>
-                  <div data-css-linked className="index_linked">
-                    <div data-css-bundled className="index_bundled">
-                      <div data-css-vanilla-global className="index_vanilla_global">
-                        <div data-css-vanilla-local className={stylesVanillaLocal.index}>
-                          <h2>CSS test</h2>
+                <div data-client-entry className="client-entry">
+                  <div data-css-modules className={cssModulesStyles.index}>
+                    <div data-css-linked className="index_linked">
+                      <div data-css-bundled className="index_bundled">
+                        <div data-css-vanilla-global className="index_vanilla_global">
+                          <div data-css-vanilla-local className={stylesVanillaLocal.index}>
+                            <h2>CSS test</h2>
+                          </div>
                         </div>
                       </div>
                     </div>
@@ -169,6 +193,10 @@ test.describe("Vite CSS dev", () => {
       await page.goto(`http://localhost:${devPort}/`, {
         waitUntil: "networkidle",
       });
+      await expect(page.locator("#index [data-client-entry]")).toHaveCSS(
+        "padding",
+        TEST_PADDING_VALUE
+      );
       await expect(page.locator("#index [data-css-modules]")).toHaveCSS(
         "padding",
         TEST_PADDING_VALUE
@@ -205,6 +233,10 @@ test.describe("Vite CSS dev", () => {
       // Ensure no errors on page load
       expect(pageErrors).toEqual([]);
 
+      await expect(page.locator("#index [data-client-entry]")).toHaveCSS(
+        "padding",
+        TEST_PADDING_VALUE
+      );
       await expect(page.locator("#index [data-css-modules]")).toHaveCSS(
         "padding",
         TEST_PADDING_VALUE
@@ -300,8 +332,28 @@ test.describe("Vite CSS dev", () => {
         UPDATED_TEST_PADDING_VALUE
       );
 
+      // Ensure CSS updates were handled by HMR
       await expect(input).toHaveValue("stateful");
 
+      // The following change triggers a full page reload, so we check it after all the checks for HMR state preservation
+      let clientEntryCssContents = await fs.readFile(
+        path.join(projectDir, "app/entry.client.css"),
+        "utf8"
+      );
+      await fs.writeFile(
+        path.join(projectDir, "app/entry.client.css"),
+        clientEntryCssContents.replace(
+          TEST_PADDING_VALUE,
+          UPDATED_TEST_PADDING_VALUE
+        ),
+        "utf8"
+      );
+
+      await expect(page.locator("#index [data-client-entry]")).toHaveCSS(
+        "padding",
+        UPDATED_TEST_PADDING_VALUE
+      );
+
       expect(pageErrors).toEqual([]);
     });
   });

packages/remix-dev/vite/import-vite-esm-sync.ts

@@ -0,0 +1,21 @@
+// This file is used to avoid CJS deprecation warnings in Vite 5 since
+// @remix-run/dev currently compiles to CJS. By using this interface, we only
+// ever access the Vite package via a dynamic import which forces the ESM build.
+// "importViteAsync" is expected be called up-front in the first async plugin
+// hook, which then unlocks "importViteEsmSync" for use anywhere in the plugin
+// and its utils. This file won't be needed when this package is ESM only.
+
+import invariant from "../invariant";
+
+// eslint-disable-next-line @typescript-eslint/consistent-type-imports
+type Vite = typeof import("vite");
+let vite: Vite | undefined;
+
+export async function preloadViteEsm(): Promise<void> {
+  vite = await import("vite");
+}
+
+export function importViteEsmSync(): Vite {
+  invariant(vite, "importViteEsmSync() called before preloadViteEsm()");
+  return vite;
+}