fix(router-core): ensure rewrite basepath applies consistently

packages/react-router/src/Transitioner.tsx

@@ -52,10 +52,20 @@ export function Transitioner() {
       _includeValidateSearch: true,
     })
 
-    if (
-      trimPathRight(router.latestLocation.href) !==
-      trimPathRight(nextLocation.href)
-    ) {
+    const latestPublicHref = trimPathRight(router.latestLocation.publicHref)
+    const nextPublicHref = trimPathRight(nextLocation.publicHref)
+
+    if (latestPublicHref !== nextPublicHref) {
+      const latestOrigin = new URL(router.latestLocation.url).origin
+      const nextOrigin = new URL(nextLocation.url).origin
+
+      if (latestOrigin !== nextOrigin) {
+        if (typeof window !== 'undefined') {
+          window.location.href = nextLocation.url
+        }
+        return
+      }
+
       router.commitLocation({ ...nextLocation, replace: true })
     }
 

packages/react-router/tests/router.test.tsx

@@ -2809,6 +2809,72 @@ describe('basepath', () => {
     expect(router.state.location.pathname).toBe('/test')
   })
 
+  it('should handle basepath when accessing root path and maintain basepath in browser URL', async () => {
+    const rootRoute = createRootRoute({
+      component: () => <Outlet />,
+    })
+
+    const indexRoute = createRoute({
+      getParentRoute: () => rootRoute,
+      path: '/',
+      component: () => <div data-testid="home">Home</div>,
+    })
+
+    const routeTree = rootRoute.addChildren([indexRoute])
+
+    const history = createMemoryHistory({
+      initialEntries: ['/my-app/'],
+    })
+
+    const router = createRouter({
+      routeTree,
+      history,
+      basepath: '/my-app',
+    })
+
+    render(<RouterProvider router={router} />)
+
+    await waitFor(() => {
+      expect(screen.getByTestId('home')).toBeInTheDocument()
+    })
+
+    expect(router.state.location.pathname).toBe('/')
+    expect(history.location.pathname).toBe('/my-app/')
+  })
+
+  it('should handle basepath option for backward compatibility', async () => {
+    const rootRoute = createRootRoute({
+      component: () => <Outlet />,
+    })
+
+    const indexRoute = createRoute({
+      getParentRoute: () => rootRoute,
+      path: '/',
+      component: () => <div data-testid="home">Home</div>,
+    })
+
+    const routeTree = rootRoute.addChildren([indexRoute])
+
+    const history = createMemoryHistory({
+      initialEntries: ['/my-app/'],
+    })
+
+    const router = createRouter({
+      routeTree,
+      history,
+      basepath: '/my-app',
+    })
+
+    render(<RouterProvider router={router} />)
+
+    await waitFor(() => {
+      expect(screen.getByTestId('home')).toBeInTheDocument()
+    })
+
+    expect(router.state.location.pathname).toBe('/')
+    expect(history.location.pathname).toBe('/my-app/')
+  })
+
   it('should combine basepath with additional input rewrite logic', async () => {
     const rootRoute = createRootRoute({
       component: () => <Outlet />,

packages/router-core/src/router.ts

@@ -1804,8 +1804,12 @@ export class RouterCore<
       return isEqual
     }
 
+    const latestPublicHref =
+      this.latestLocation.publicHref ?? this.latestLocation.href
+    const nextPublicHref = next.publicHref ?? next.href
+
     const isSameUrl =
-      trimPathRight(this.latestLocation.href) === trimPathRight(next.href)
+      trimPathRight(latestPublicHref) === trimPathRight(nextPublicHref)
 
     const previousCommitPromise = this.commitLocationPromise
     this.commitLocationPromise = createControlledPromise<void>(() => {

packages/solid-router/src/Transitioner.tsx

@@ -50,10 +50,10 @@ export function Transitioner() {
       _includeValidateSearch: true,
     })
 
-    if (
-      trimPathRight(router.latestLocation.href) !==
-      trimPathRight(nextLocation.href)
-    ) {
+    const latestPublicHref = trimPathRight(router.latestLocation.publicHref)
+    const nextPublicHref = trimPathRight(nextLocation.publicHref)
+
+    if (latestPublicHref !== nextPublicHref) {
       router.commitLocation({ ...nextLocation, replace: true })
     }