Fix dynamic prerender conflict (#10298)

* Reproduce issues

* Handle inconsistency between static, dynamic and rest routes

* Add extra test cases

* Add changeset

* Revert unrelated changes

* Update lockfile

.changeset/strange-forks-exist.md

@@ -0,0 +1,5 @@
+---
+"astro": patch
+---
+
+Fix an incorrect conflict resolution between pages generated from static routes and rest parameters

packages/astro/src/core/build/generate.ts

@@ -326,7 +326,7 @@ async function getPathsForRoute(
 	let paths: Array<string> = [];
 	if (route.pathname) {
 		paths.push(route.pathname);
-		builtPaths.add(route.pathname);
+		builtPaths.add(removeTrailingForwardSlash(route.pathname));
 	} else {
 		const staticPaths = await callGetStaticPaths({
 			mod,

packages/astro/src/core/routing/manifest/generator.ts

@@ -37,5 +37,13 @@ export function getRouteGenerator(
 		trailing = '/';
 	}
 	const toPath = compile(template + trailing);
-	return toPath;
+	return (params: object): string => {
+		const path = toPath(params);
+		
+		// When generating an index from a rest parameter route, `path-to-regexp` will return an
+		// empty string instead "/". This causes an inconsistency with static indexes that may result
+		// in the incorrect routes being rendered.
+		// To fix this, we return "/" when the path is empty.
+		return path || '/';
+	};
 }

packages/astro/test/dynamic-route-collision.test.js

@@ -0,0 +1,59 @@
+import assert from 'node:assert/strict';
+import { before, describe, it } from 'node:test';
+import * as cheerio from 'cheerio';
+import { loadFixture } from './test-utils.js';
+
+describe('Dynamic route collision', () => {
+	/** @type {import('./test-utils').Fixture} */
+	let fixture;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: './fixtures/dynamic-route-collision',
+		});
+
+		await fixture.build().catch(console.log);
+	});
+
+	it('Builds a static route when in conflict with a dynamic route', async () => {
+		const html = await fixture.readFile('/about/index.html');
+		const $ = cheerio.load(html);
+		assert.equal($('h1').text(), 'Static About');
+	});
+
+	it('Builds a static route when in conflict with a spread route', async () => {
+		const html = await fixture.readFile('/who/index.html');
+		const $ = cheerio.load(html);
+		assert.equal($('h1').text(), 'Static Who We Are');
+	});
+
+	it('Builds a static nested index when in conflict with a spread route', async () => {
+		const html = await fixture.readFile('/tags/index.html');
+		const $ = cheerio.load(html);
+		assert.equal($('h1').text(), 'Static Tags Index');
+	});
+
+	it('Builds a static root index when in conflict with a spread route', async () => {
+		const html = await fixture.readFile('/index.html');
+		const $ = cheerio.load(html);
+		assert.equal($('h1').text(), 'Static Index');
+	});
+
+	it('Builds a static index a nested when in conflict with a dynamic+spread route', async () => {
+		const html = await fixture.readFile('/en/index.html');
+		const $ = cheerio.load(html);
+		assert.equal($('h1').text(), 'Dynamic-only Localized Index');
+	});
+
+	it('Builds a dynamic route when in conflict with a spread route', async () => {
+		const html = await fixture.readFile('/blog/index.html');
+		const $ = cheerio.load(html);
+		assert.equal($('h1').text(), 'Dynamic Blog');
+	});
+
+	it('Builds the highest priority route out of two conflicting dynamic routes', async () => {
+		const html = await fixture.readFile('/order/index.html');
+		const $ = cheerio.load(html);
+		assert.equal($('h1').text(), 'Order from A');
+	});
+});

packages/astro/test/fixtures/dynamic-route-collision/package.json

@@ -0,0 +1,8 @@
+{
+  "name": "@test/dynamic-route-collision",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "astro": "workspace:*"
+  }
+}

packages/astro/test/fixtures/dynamic-route-collision/src/pages/[...slug].astro

@@ -0,0 +1,35 @@
+---
+export async function getStaticPaths() {
+	const pages = [
+		{
+			slug: undefined,
+			title: 'Rest Index',
+		},
+		{
+			slug: 'blog',
+			title: 'Rest Blog',
+		},
+		{
+			slug: 'who',
+			title: 'Rest Who We Are',
+		},
+	];
+	return pages.map(({ slug, title }) => {
+		return {
+			params: { slug },
+			props: { title },
+		};
+	});
+}
+
+const { title } = Astro.props;
+---
+
+<html>
+	<head>
+		<title>{title}</title>
+	</head>
+	<body>
+		<h1>{title}</h1>
+	</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/[aOrder].astro

@@ -0,0 +1,27 @@
+---
+export async function getStaticPaths() {
+	const pages = [
+		{
+			page: 'order',
+			title: 'Order from A',
+		},
+	];
+	return pages.map(({ page, title }) => {
+		return {
+			params: { 'aOrder': page },
+			props: { title },
+		};
+	});
+}
+
+const { title } = Astro.props;
+---
+
+<html>
+<head>
+	<title>{title}</title>
+</head>
+<body>
+<h1>{title}</h1>
+</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/[bOrder].astro

@@ -0,0 +1,27 @@
+---
+export async function getStaticPaths() {
+	const pages = [
+		{
+			page: 'order',
+			title: 'Order from B',
+		},
+	];
+	return pages.map(({ page, title }) => {
+		return {
+			params: { 'bOrder': page },
+			props: { title },
+		};
+	});
+}
+
+const { title } = Astro.props;
+---
+
+<html>
+<head>
+	<title>{title}</title>
+</head>
+<body>
+<h1>{title}</h1>
+</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/[locale]/[...page].astro

@@ -0,0 +1,28 @@
+---
+export async function getStaticPaths() {
+	const pages = [
+		{
+			locale: 'en',
+			page: undefined,
+			title: 'Dynamic+Rest Localized Index',
+		},
+	];
+	return pages.map(({ page, locale, title }) => {
+		return {
+			params: { page, locale },
+			props: { title },
+		};
+	});
+}
+
+const { title } = Astro.props;
+---
+
+<html>
+	<head>
+		<title>{title}</title>
+	</head>
+	<body>
+		<h1>{title}</h1>
+	</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/[locale]/index.astro

@@ -0,0 +1,27 @@
+---
+export async function getStaticPaths() {
+	const pages = [
+		{
+			locale: 'en',
+			title: 'Dynamic-only Localized Index',
+		},
+	];
+	return pages.map(({ page, locale, title }) => {
+		return {
+			params: { page, locale },
+			props: { title },
+		};
+	});
+}
+
+const { title } = Astro.props;
+---
+
+<html>
+<head>
+	<title>{title}</title>
+</head>
+<body>
+<h1>{title}</h1>
+</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/[page].astro

@@ -0,0 +1,31 @@
+---
+export async function getStaticPaths() {
+	const pages = [
+		{
+			page: 'about',
+			title: 'Dynamic About',
+		},
+		{
+			page: 'blog',
+			title: 'Dynamic Blog',
+		},
+	];
+	return pages.map(({ page, title }) => {
+		return {
+			params: { page },
+			props: { title },
+		};
+	});
+}
+
+const { title } = Astro.props;
+---
+
+<html>
+<head>
+	<title>{title}</title>
+</head>
+<body>
+<h1>{title}</h1>
+</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/about.astro

@@ -0,0 +1,8 @@
+<html>
+	<head>
+		<title>Static About Page</title>
+	</head>
+	<body>
+		<h1>Static About</h1>
+	</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/index.astro

@@ -0,0 +1,8 @@
+<html>
+	<head>
+		<title>Static Index Page</title>
+	</head>
+	<body>
+		<h1>Static Index</h1>
+	</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/tags/[...page].astro

@@ -0,0 +1,27 @@
+---
+export async function getStaticPaths() {
+	const pages = [
+		{
+			page: undefined,
+			title: 'Rest Tag Index',
+		},
+	];
+	return pages.map(({ page, title }) => {
+		return {
+			params: { tag: page },
+			props: { title },
+		};
+	});
+}
+
+const { title } = Astro.props;
+---
+
+<html>
+	<head>
+		<title>{title}</title>
+	</head>
+	<body>
+		<h1>{title}</h1>
+	</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/tags/index.astro

@@ -0,0 +1,8 @@
+<html>
+	<head>
+		<title>Static Tags Index</title>
+	</head>
+	<body>
+		<h1>Static Tags Index</h1>
+	</body>
+</html>

packages/astro/test/fixtures/dynamic-route-collision/src/pages/who.astro

@@ -0,0 +1,8 @@
+<html>
+	<head>
+		<title>Static Who We Are</title>
+	</head>
+	<body>
+		<h1>Static Who We Are</h1>
+	</body>
+</html>

pnpm-lock.yaml

@@ -2732,6 +2732,12 @@ importers:
         specifier: workspace:*
         version: link:../../..
 
+  packages/astro/test/fixtures/dynamic-route-collision:
+    dependencies:
+      astro:
+        specifier: workspace:*
+        version: link:../../..
+
   packages/astro/test/fixtures/entry-file-names:
     dependencies:
       '@astrojs/preact':