Well, do we need to follow up on backward-compatibility between 1.4.x and 2.x? The current behavior looks reasonable to me.

Good question, I don't know. I'm trying to think of a scenario where it would be necessary or easier to use query params instead of an optional named route parameter. Maybe the old behavior was accidental.

@synecy would you like to weigh in on this?

@namusyaka I'm thinking it might be a nice feature if I had to dynamically build links or form data to use query params, but also to have the option of creating direct links using the (optional) named route params.

I suppose you could just create two separate routes if that was they case tho. One without the param and one with the named parameter being required.

Should it be released as a new feature?

I'm sorry, but I'm still thinking that the feature is not useful to me..
Could you write down your design with code examples?

@namusyaka I honestly don't feel that strongly about this feature. I'm happy to close this PR and #1666 as a non-issue. I think if this was an issue, the workaround would be to just define an additional route without the optional named route parameters.

If I recall, our use case was something like this:

/test/123-123-123
/test?user_id[]=123-123-123&user_id[]=456-456-456

which no longer works in 2.x, however we've since added workarounds by either adding multiple routes or manually copying from rack.request.query_hash to restore original behavior. I think the problem with adding new routes is that if you have multiple optionals like:

/?:one?/something/?:two?/test

the number of routes you have to add in order to support every possible case gets out of hand pretty quick.

@synecy Thanks for your explanation. I got your pain point on v2.x.x.

@jkowens Your patch looks reasonable to me. Merging.

Hey thanks @namusyaka. As @dentarg mentioned, I have already created a 2.2.0 tag on master.

I marked this as v3.0.0. Will cut a new release based on the v2.2.0 tag.
@jkowens Could you add this change in CHANGELOG?

Released:

• https://rubygems.org/gems/sinatra/versions/2.2.0
• https://rubygems.org/gems/sinatra-contrib/versions/2.2.0
• https://rubygems.org/gems/rack-protection/versions/2.2.0