From c78253aaf3df7b4c6a70e41b889aac231319085f Mon Sep 17 00:00:00 2001
From: Brenley Dueck <brenleydueck@gmail.com>
Date: Thu, 10 Sep 2026 17:25:12 -0500
Subject: [PATCH] fix: only strip a whole `index` segment in routePathFromFile

Route files whose names merely end in "index" (e.g. `routes/reindex.tsx`)
were mapped to `/re` instead of `/reindex` because the nested convention
used an unanchored `/index$/` replace. Anchor the strip to a segment
boundary so only a real `index` file maps to its directory's path.

Same fix as solidjs/solid-start#2315 for solidjs/solid-start#2314.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
---
 .changeset/index-suffix-segment.md |  5 +++++
 src/convention.ts                  |  3 ++-
 test/convention.spec.ts            | 23 +++++++++++++++++++++++
 3 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/index-suffix-segment.md

diff --git a/.changeset/index-suffix-segment.md b/.changeset/index-suffix-segment.md
new file mode 100644
index 0000000..28567ea
--- /dev/null
+++ b/.changeset/index-suffix-segment.md
@@ -0,0 +1,5 @@
+---
+"filesystem-routing": patch
+---
+
+Only strip a whole `index` segment when mapping route files to paths. Route files whose names merely end in "index", such as `routes/reindex.tsx`, were previously mapped to `/re` instead of `/reindex`.
diff --git a/src/convention.ts b/src/convention.ts
index 5ea36b8..3693db8 100644
--- a/src/convention.ts
+++ b/src/convention.ts
@@ -14,7 +14,8 @@ export function routePathFromFile(routeFile: string): string {
   const routePath = routeFile
     // remove the initial slash
     .slice(1)
-    .replace(/index$/, "")
+    // only strip a whole `index` segment, not a name that merely ends in "index" (e.g. `reindex`)
+    .replace(/(^|\/)index$/, "$1")
     .replace(/\[([^/]+)\]/g, (_, m) => {
       if (m.length > 3 && m.startsWith("...")) {
         return `*${m.slice(3)}`;
diff --git a/test/convention.spec.ts b/test/convention.spec.ts
index 2dcd943..8ac4a7f 100644
--- a/test/convention.spec.ts
+++ b/test/convention.spec.ts
@@ -28,6 +28,16 @@ describe("routePathFromFile", () => {
   it("retains group segments for emission adapters", () => {
     expect(routePathFromFile("/(marketing)/about")).toBe("/(marketing)/about");
   });
+
+  // https://github.com/solidjs/solid-start/issues/2314
+  it("only strips index as a whole segment, not as a filename suffix", () => {
+    expect(routePathFromFile("/reindex")).toBe("/reindex");
+    expect(routePathFromFile("/myindex")).toBe("/myindex");
+    expect(routePathFromFile("/appendix")).toBe("/appendix");
+    expect(routePathFromFile("/blog/reindex")).toBe("/blog/reindex");
+    expect(routePathFromFile("/reindex/index")).toBe("/reindex/");
+    expect(routePathFromFile("/[id]/index")).toBe("/:id/");
+  });
 });
 
 const temporaryDirectories: string[] = [];
@@ -75,6 +85,19 @@ describe("PageFileSystemRouter", () => {
     expect(post.$$route?.pick).toEqual(["route"]);
   });
 
+  it("keeps route files whose names end in index at their own path", async () => {
+    const dir = createRouteTree({
+      "reindex.tsx": "export default () => <h1>Reindex</h1>;",
+      "blog/index.tsx": "export default () => <h1>Blog</h1>;",
+      "blog/myindex.tsx": "export default () => <h1>My index</h1>;"
+    });
+    const router = new PageFileSystemRouter({ dir, extensions: ["tsx"] });
+
+    const paths = (await router.getRoutes()).map(route => route.path).sort();
+
+    expect(paths).toEqual(["/blog/", "/blog/myindex", "/reindex"]);
+  });
+
   it("resolves a relative dir against the current working directory", async () => {
     const dir = createRouteTree({
       "index.tsx": "export default () => <h1>Home</h1>;",