refactor(remix-dev): flat routes perf improvements

.changeset/flat-routes-perf.md

@@ -0,0 +1,6 @@
+---
+"remix": patch
+"@remix-run/dev": patch
+---
+
+flat routes perf improvements

integration/flat-routes-test.ts

@@ -11,10 +11,19 @@ let fixture: Fixture;
 let appFixture: AppFixture;
 
 test.describe("flat routes", () => {
+  let IGNORED_ROUTE = "/ignore-me-pls";
   test.beforeAll(async () => {
     fixture = await createFixture({
-      future: { v2_routeConvention: true },
       files: {
+        "remix.config.js": js`
+          /** @type {import('@remix-run/dev').AppConfig} */
+          module.exports = {
+            future: {
+              v2_routeConvention: true,
+            },
+            ignoredRouteFiles: ['${IGNORED_ROUTE}'],
+          };
+        `,
         "app/root.jsx": js`
           import { Links, Meta, Outlet, Scripts } from "@remix-run/react";
 
@@ -79,6 +88,12 @@ test.describe("flat routes", () => {
             return <h3>Dashboard Index</h3>;
           }
         `,
+
+        [`app/routes/${IGNORED_ROUTE}.jsx`]: js`
+          export default function () {
+            return <h2>i should 404</h2>;
+          }
+        `,
       },
     });
 
@@ -146,6 +161,12 @@ test.describe("flat routes", () => {
 </div>`);
     });
   }
+
+  test("allows ignoredRouteFiles to be configured", async ({ page }) => {
+    let routeIds = Object.keys(fixture.build.routes);
+
+    expect(routeIds).not.toContain(IGNORED_ROUTE);
+  });
 });
 
 test.describe("warns when v1 routesConvention is used", () => {
@@ -188,7 +209,7 @@ test.describe("warns when v1 routesConvention is used", () => {
     console.error = originalConsoleError;
   });
 
-  test("warns about conflicting routes", () => {
+  test("v2_routeConvention is not enabled", () => {
     console.log(buildOutput);
     expect(buildOutput).toContain(flatRoutesWarning);
   });
@@ -249,3 +270,45 @@ test.describe("emits warnings for route conflicts", async () => {
     expect(buildOutput).toContain(`⚠️ Route Path Collision: "/"`);
   });
 });
+
+test.describe("", () => {
+  let buildStdio = new PassThrough();
+  let buildOutput: string;
+
+  let originalConsoleLog = console.log;
+  let originalConsoleWarn = console.warn;
+  let originalConsoleError = console.error;
+
+  test.beforeAll(async () => {
+    console.log = () => {};
+    console.warn = () => {};
+    console.error = () => {};
+    await createFixtureProject({
+      buildStdio,
+      future: { v2_routeConvention: true },
+      files: {
+        "app/routes/_index/route.jsx": js``,
+        "app/routes/_index/utils.js": js``,
+      },
+    });
+
+    let chunks: Buffer[] = [];
+    buildOutput = await new Promise<string>((resolve, reject) => {
+      buildStdio.on("data", (chunk) => chunks.push(Buffer.from(chunk)));
+      buildStdio.on("error", (err) => reject(err));
+      buildStdio.on("end", () =>
+        resolve(Buffer.concat(chunks).toString("utf8"))
+      );
+    });
+  });
+
+  test.afterAll(() => {
+    console.log = originalConsoleLog;
+    console.warn = originalConsoleWarn;
+    console.error = originalConsoleError;
+  });
+
+  test("doesn't emit a warning for nested index files with co-located files", () => {
+    expect(buildOutput).not.toContain(`Route Path Collision`);
+  });
+});