`route.tsx` changes whether trailing slashes are required in links to `index.tsx`

[twiddler]

Describe the bug

With file-based routing, foo/route.tsx changes whether links to foo/index.tsx must be /foo/ or /foo:

1. If foo/route.tsx does not exist, foo/index.tsx can be linked to only with /foo/, not /foo.
2. If foo/route.tsx does exist, foo/index.tsx can be linked to only with /foo, not /foo/.

Your Example Website or App

https://stackblitz.com/edit/github-fzqvge?file=src%2Froutes%2F__root.tsx

Steps to Reproduce the Bug or Issue

1. Use file-based routing.
2. In a directory that has an index.tsx, create a route.tsx.

Expected behavior

In the given StackBlitz example, I expected either

• the trailing slash to always be required, or
• the trailing slash to never be required,

i.e. I did not expect the presence of route.tsx to change the links to index.tsx.

Screenshots or Videos

Platform

StackBlitz

Additional context

No response

[TkDodo]

fyi, I have a similar setup but we use trailingSlash: 'always' and that seems to work better for us:

https://stackblitz.com/edit/github-fzqvge-yfunzp?file=src%2Fmain.tsx,src%2Froutes%2F__root.tsx

basically, without an index.tsx route, you can't navigate there at all. That makes sense to me because route.tsx is just a layout that renders something + an outlet. Once you have an index.tsx page, even if it renders () => null, you have a concrete route to navigate to.

There seems to be an additional bug though with the types when there is just an index.tsx but no route.tsx. The types seem to be a bit off, because I get these as possible to targets:

"/nested-with-route/" | "/flat-with-route/" | "/" | "./" | "../" | "/nested-no-route//" | "/flat-no-route//" | undefined'. Did you mean '"/flat-no-route//"'

note that the -no-route routes have two slashes at the end 😅 .

@chorobin this might be something to look at

[chorobin]

I think it's a bug in the generator. We moved the full path logic to there instead of TS doing it. And before I think TS was removing trailing slashes for fullPath and then we added it back depending on the setting. Now the generator produces a trailing slash and we add another trailing slash!

[twiddler]

We did see some new type errors after upgrading to v1.32.2 which led me to this experiment, so quite possibly yes. (I did not test this with pre-v1.32.2.)

[chorobin]

Yep. I know where to fix it. Will get a pr up. Not all index routes should have a trailing slash I guess. Only those that uniquely identified by one