Wrong destination path calculated on navigation when "basepath" is set for Router

[vasiliy-l]

Which project does this relate to?

Router

Describe the bug

The issue reproduces when creating Router instance with basepath router option specified.

When navigating via <Link> or using the function from useNavigate hook, it does not work properly if the to property/ option is not specified.
In this case, the core router logic takes fullPath value from the latest route match which does not include the base path part:

router/packages/router-core/src/router.ts

Lines 1438 to 1441 in bab29d0

	// Resolve the next to
	const nextTo = dest.to
	? this.resolvePathWithBase(fromPath, `${dest.to}`)
	: fromPath

The navigation works as expected if the to property/option is specified, as a full or relative path.

Your Example Website or App

https://stackblitz.com/edit/github-cwqd7wap?file=src%2Fmain.tsx

Steps to Reproduce the Bug or Issue

Create a Router instance with basepath option specified.

const router = createRouter({
  routeTree,
  basepath: '/base', 
  // ...
});

Navigate using <Link> or useNavigate hook. Do not specify to property/option.

// Navigated to /base/some-page 

// Navigates to "/some-page?foo=bar" instead of "/base/some-page?foo-bar"
<Link search={{ foo: 'bar' }}>Update search params</Link>

// Also navigates to "/some-page?foo=bar" instead of "/base/some-page?foo-bar"
const navigate = useNavigate();
navigate({ search: { foo: 'bar'  } });

Expected behavior

When the to property/option is not specified, the destination path is expected be calculated properly including base path.

Screenshots or Videos

No response

Platform

• OS: any
• Browser: any
• Version: "@tanstack/react-router": "^1.121.0"

Additional context

No response

[empotts]

also running into this

[gynekolog]

Same. Using to="." doesn't change the behavior.

// Navigates to "/some-page?foo=bar" instead of "/base/some-page?foo-bar"
<Link to={"."} search={{ foo: 'bar' }}>Update search params</Link>

[jvllmr]

Did anyone find out in what version the regression happened? Using i.e. useNavigate this way worked for me before.

[schiller-manuel]

probably caused by 1.121.0