fix(core): filter out duplicate routes and log warning

ref vitebook#28

packages/core/src/node/app/create/resolvePages.ts

@@ -56,7 +56,9 @@ export async function resolvePages(
     }
   }
 
-  app.pages = sortPages(Array.from(resolvedPages.values()));
+  app.pages = filterDuplicateRoutes(
+    sortPages(Array.from(resolvedPages.values())),
+  );
 
   // `pagesResolved` hook
   for (let i = 0; i < app.plugins.length; i += 1) {
@@ -179,6 +181,33 @@ export function loadPagesVirtualModule(app: App): string {
   )}`;
 }
 
+export function filterDuplicateRoutes(pages: ServerPage[]): ServerPage[] {
+  const seen = new Map();
+  const filteredPages: ServerPage[] = [];
+
+  for (const page of pages) {
+    if (seen.has(page.route)) {
+      const routeOwner = seen.get(page.route);
+
+      const fileA = `${kleur.bold('Belongs To:')} ${routeOwner.rootPath}\n`;
+      const fileB = `${kleur.bold('Duplicate (ignored):')} ${page.rootPath}\n`;
+
+      logger.warn(
+        logger.formatWarnMsg(
+          `Found duplicate route: ${kleur.bold(
+            page.route,
+          )}\n\n${fileA}\n${fileB}`,
+        ),
+      );
+    } else {
+      seen.set(page.route, page);
+      filteredPages.push(page);
+    }
+  }
+
+  return filteredPages;
+}
+
 // Splits route by `/` and retain splitter.
 const splitRouteRE = /(.*?\/)/g;
 const splitRoute = (route: string) => route.split(splitRouteRE).slice(3);