[remix] Add unit tests (#9469)

Moves parts of the `@vercel/remix` builder into util functions that have isolated unit tests. No functionality changes.

packages/remix/src/build.ts

@@ -1,7 +1,6 @@
 import { Project } from 'ts-morph';
 import { promises as fs } from 'fs';
 import { basename, dirname, extname, join, relative, sep } from 'path';
-import { pathToRegexp, Key } from 'path-to-regexp';
 import {
   debug,
   download,
@@ -30,7 +29,12 @@ import type {
   BuildResultV2Typical,
 } from '@vercel/build-utils';
 import type { ConfigRoute } from '@remix-run/dev/dist/config/routes';
-import { findConfig } from './utils';
+import {
+  findConfig,
+  getPathFromRoute,
+  getRegExpFromPath,
+  isLayoutRoute,
+} from './utils';
 
 const _require: typeof require = eval('require');
 
@@ -173,12 +177,13 @@ module.exports = config;`;
     }
   }
 
-  const { serverBuildPath, routes: remixRoutes } = remixConfig;
+  const { serverBuildPath } = remixConfig;
+  const remixRoutes = Object.values(remixConfig.routes);
 
   // Figure out which pages should be edge functions
   const edgePages = new Set<ConfigRoute>();
   const project = new Project();
-  for (const route of Object.values(remixRoutes)) {
+  for (const route of remixRoutes) {
     const routePath = join(remixConfig.appDirectory, route.file);
     const staticConfig = getConfig(project, routePath);
     const isEdge =
@@ -228,27 +233,11 @@ module.exports = config;`;
     },
   ];
 
-  for (const route of Object.values(remixRoutes)) {
+  for (const route of remixRoutes) {
     // Layout routes don't get a function / route added
-    const isLayoutRoute = Object.values(remixRoutes).some(
-      r => r.parentId === route.id
-    );
-    if (isLayoutRoute) continue;
-
-    // Build up the full request path
-    let currentRoute: ConfigRoute | undefined = route;
-    const pathParts: string[] = [];
-    do {
-      if (currentRoute.index) pathParts.push('index');
-      if (currentRoute.path) pathParts.push(currentRoute.path);
-      if (currentRoute.parentId) {
-        currentRoute = remixRoutes[currentRoute.parentId];
-      } else {
-        currentRoute = undefined;
-      }
-    } while (currentRoute);
-    const path = join(...pathParts.reverse());
+    if (isLayoutRoute(route.id, remixRoutes)) continue;
 
+    const path = getPathFromRoute(route, remixConfig.routes);
     const isEdge = edgePages.has(route);
     const fn =
       isEdge && edgeFunction
@@ -264,13 +253,8 @@ module.exports = config;`;
     output[path] = fn;
 
     // If this is a dynamic route then add a Vercel route
-    const keys: Key[] = [];
-    // Replace "/*" at the end to handle "splat routes"
-    const splatPath = '/:params+';
-    const rePath =
-      path === '*' ? splatPath : `/${path.replace(/\/\*$/, splatPath)}`;
-    const re = pathToRegexp(rePath, keys);
-    if (keys.length > 0) {
+    const re = getRegExpFromPath(path);
+    if (re) {
       routes.push({
         src: re.source,
         dest: path,

packages/remix/src/utils.ts

@@ -1,5 +1,10 @@
-import { existsSync } from 'fs';
 import { join } from 'path';
+import { existsSync } from 'fs';
+import { pathToRegexp, Key } from 'path-to-regexp';
+import type {
+  ConfigRoute,
+  RouteManifest,
+} from '@remix-run/dev/dist/config/routes';
 
 const configExts = ['.js', '.cjs', '.mjs'];
 
@@ -12,3 +17,39 @@ export function findConfig(dir: string, basename: string): string | undefined {
 
   return undefined;
 }
+
+export function isLayoutRoute(
+  routeId: string,
+  routes: Pick<ConfigRoute, 'id' | 'parentId'>[]
+): boolean {
+  return routes.some(r => r.parentId === routeId);
+}
+
+export function getPathFromRoute(
+  route: ConfigRoute,
+  routes: RouteManifest
+): string {
+  let currentRoute: ConfigRoute | undefined = route;
+  const pathParts: string[] = [];
+  do {
+    if (currentRoute.index) pathParts.push('index');
+    if (currentRoute.path) pathParts.push(currentRoute.path);
+    if (currentRoute.parentId) {
+      currentRoute = routes[currentRoute.parentId];
+    } else {
+      currentRoute = undefined;
+    }
+  } while (currentRoute);
+  const path = pathParts.reverse().join('/');
+  return path;
+}
+
+export function getRegExpFromPath(path: string): RegExp | false {
+  const keys: Key[] = [];
+  // Replace "/*" at the end to handle "splat routes"
+  const splatPath = '/:params+';
+  const rePath =
+    path === '*' ? splatPath : `/${path.replace(/\/\*$/, splatPath)}`;
+  const re = pathToRegexp(rePath, keys);
+  return keys.length > 0 ? re : false;
+}