From 4e58a0708106e751b2efb1d53ac7d9a6fcfcb289 Mon Sep 17 00:00:00 2001
From: joseph0926 <joseph0926@naver.com>
Date: Fri, 14 Nov 2025 10:33:26 +0900
Subject: [PATCH] fix: handle notFound from params.parse correctly

---
 packages/router-core/src/router.ts      | 12 +++--
 packages/router-core/tests/load.test.ts | 60 +++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 4 deletions(-)

diff --git a/packages/router-core/src/router.ts b/packages/router-core/src/router.ts
index 962c536045a..1cd71467300 100644
--- a/packages/router-core/src/router.ts
+++ b/packages/router-core/src/router.ts
@@ -1379,7 +1379,7 @@ export class RouterCore<
 
       const strictParams = existingMatch?._strictParams ?? usedParams
 
-      let paramsError: PathParamError | undefined = undefined
+      let paramsError: unknown = undefined
 
       if (!existingMatch) {
         const strictParseParams =
@@ -1392,9 +1392,13 @@ export class RouterCore<
               strictParseParams(strictParams as Record<string, string>),
             )
           } catch (err: any) {
-            paramsError = new PathParamError(err.message, {
-              cause: err,
-            })
+            if (isNotFound(err) || isRedirect(err)) {
+              paramsError = err
+            } else {
+              paramsError = new PathParamError(err.message, {
+                cause: err,
+              })
+            }
 
             if (opts?.throwOnError) {
               throw paramsError
diff --git a/packages/router-core/tests/load.test.ts b/packages/router-core/tests/load.test.ts
index be9c248ac12..d65d37cf747 100644
--- a/packages/router-core/tests/load.test.ts
+++ b/packages/router-core/tests/load.test.ts
@@ -509,6 +509,66 @@ test('cancelMatches after pending timeout', async () => {
   expect(cancelledFooMatch?._nonReactive.pendingTimeout).toBeUndefined()
 })
 
+describe('params.parse notFound', () => {
+  test('throws notFound on invalid params', async () => {
+    const rootRoute = new BaseRootRoute({})
+    const testRoute = new BaseRoute({
+      getParentRoute: () => rootRoute,
+      path: '/test/$id',
+      params: {
+        parse: ({ id }: { id: string }) => {
+          const parsed = parseInt(id, 10)
+          if (Number.isNaN(parsed)) {
+            throw notFound()
+          }
+          return { id: parsed }
+        },
+      },
+    })
+    const routeTree = rootRoute.addChildren([testRoute])
+    const router = new RouterCore({
+      routeTree,
+      history: createMemoryHistory({ initialEntries: ['/test/invalid'] }),
+    })
+
+    await router.load()
+
+    const match = router.state.pendingMatches?.find(
+      (m) => m.routeId === testRoute.id,
+    )
+
+    expect(match?.status).toBe('notFound')
+  })
+
+  test('succeeds on valid params', async () => {
+    const rootRoute = new BaseRootRoute({})
+    const testRoute = new BaseRoute({
+      getParentRoute: () => rootRoute,
+      path: '/test/$id',
+      params: {
+        parse: ({ id }: { id: string }) => {
+          const parsed = parseInt(id, 10)
+          if (Number.isNaN(parsed)) {
+            throw notFound()
+          }
+          return { id: parsed }
+        },
+      },
+    })
+    const routeTree = rootRoute.addChildren([testRoute])
+    const router = new RouterCore({
+      routeTree,
+      history: createMemoryHistory({ initialEntries: ['/test/123'] }),
+    })
+
+    await router.load()
+
+    const match = router.state.matches.find((m) => m.routeId === testRoute.id)
+    expect(match?.status).toBe('success')
+    expect(router.state.statusCode).toBe(200)
+  })
+})
+
 function sleep(ms: number) {
   return new Promise<void>((resolve) => setTimeout(resolve, ms))
 }