Fixed generation of url with optional parameter and without default value

[adamjez]

Fixed bug in generating url and added UI tests.

Currently there is a bug with generating url with optional parameter and without specifying default values
(client side rendering)

e.g. Url ControlSamples/Repeater/RouteLink/{Id?} generates /ControlSamples/Repeater/RouteLink/%7BId?}

There is still different behavior when rendering at client/server side:

• client: ControlSamples/Repeater/RouteLink/
• server: ControlSamples/Repeater/RouteLink

[adamjez]

Fixed the url generation at client side when a route contains optional parameter.

Current implementation of dotvvm routes and url generation a little bit messy. Specification of routes format doesn't exists (except source code). There exists two implementations (client and server side) which generates urls.

To correct it I would suggest these steps:

1. Create a route format specification - valid route formats with lot of examples
2. Create mechanism to share implementations of url generation. It may consists of translating UrlBuilders to javascript dynamically or sharing same regex which generates url.

I would like to hear your opinions: @exyi @djanosik

[exyi]

OK, this is probably going to work. Thanks.

[exyi]

I think that you are right with the specification, it should contain precise grammar of the route strings + the examples explaining the grammar. Actually, I'm afraid that we will need to write specification of almost everything - technically, there are no bugs in dotvvm, because the source code is the specification :)

About the translation fo UrlBuilders - I think that it is a good idea, but the JS compiler simply isn't mature enough - naively translating them now would generate ugly expression like (function (p) { return (function(_) { return "/rr" })(p) + ...)({Id: SomeExpression...}) and it would require adding support for basic Dictionary operations.

[djanosik]

It sounds good to me. But we should file another issue to solve this.

[exyi]

Merging this PR as a bug fix. I have created separate issues for the translation of UrlBuilders #526 and specification riganti/dotvvm-docs#49