Accept literals in attribute names

[RedPhoenixQ]

The parser now accepts TokenTree::Literal as names for attributes.

To prevent the name_to_string function from showing and escaping the surrounding " of a string literal the string representation is trimmed first. This should not affect how other literals work which means that both "name"="true" and 123="true" would be valid.

This also addresses the PR request in #194

[fraschm1998]

Tried this, I seem to get:

"x-on:click"="toggle" type="button" aria-controls="mobile-menu" aria-expanded ="false" { ■ element body must be wrapped in braces = help: see https://github.com/lambda-fairy/maud/pull/137 for details

[RedPhoenixQ]

Could you send more context like the macro where this element is created. This looks like and issue with missing {} for the element body or ; for a self closing element

[fraschm1998]

Could you send more context like the macro where this element is created. This looks like and issue with missing {} for the element body or ; for a self closing element

div."absolute inset-y-0 left-0 flex items-center sm:hidden" {                                                                                                                                                                                                                        
    1                                             // Mobile menu button                                                                                                                                                                                                                                                            
💥  2                                             button."relative inline-flex items-center justify-center rounded-md p-2 text-gray-400 hover:bg-gray-100 hover:text-gray-500 focus:outline-none focus:ring-2 focus:ring-inset focus:ring-indigo-500" "@click"="toggle" type="button" aria-controls="mobile-menu" aria-expanded="fa      lse" {     ■ element body must be wrapped in braces      = help: see https://github.com/lambda-fairy/maud/pull/137 for details                    
    3                                                 span."absolute -inset-0.5" {}                                                                                                                                                                                                                  
    4                                                 span."sr-only" { "Open main menu" }                                                                                                                                                                                                            
    5                                                 // Icon when menu is closed.                                                                                                                                                                                                                   
    6                                                 @for (item, path) in [("block", "M3.75 6.75h16.5M3.75 12h16.5m-16.5 5.25h16.5"), ("hidden", "M6 18L18 6M6 6l12 12")] {                                                                                                                         
    7                                                     svg.{ (item) " h-6 w-6" } fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor" aria-hidden="true" {                                                                                                                                                  
    8                                                         path stroke-linecap="round" stroke-linejoin="round" d=(path) {}                                                                                                                                                                                                      
    9                                                     }                                                                                                                                                                                                                                                                        
   10                                                 }                                                                                                                                                                                                                                                                            
   11                                             }                                                                                                                                                                                                                                                                                
   12                                         } 

[RedPhoenixQ]

I'm unable to reproduce the issue when copying the elements you sent. On the code that includes this PR it compiles for me and seemingly give the correct html.

This is the html string your code produces:
"<div class=\"absolute inset-y-0 left-0 flex items-center sm:hidden\"><button class=\"relative inline-flex items-center justify-center rounded-md p-2 text-gray-400 hover:bg-gray-100 hover:text-gray-500 focus:outline-none focus:ring-2 focus:ring-inset focus:ring-indigo-500\" @click=\"toggle\" type=\"button\" aria-controls=\"mobile-menu\" aria-expanded=\"false\"><span class=\"absolute -inset-0.5\"></span><span class=\"sr-only\">Open main menu</span><svg class=\"block h-6 w-6\" fill=\"none\" viewBox=\"0 0 24 24\" stroke-width=\"1.5\" stroke=\"currentColor\" aria-hidden=\"true\"><path stroke-linecap=\"round\" stroke-linejoin=\"round\" d=\"M3.75 6.75h16.5M3.75 12h16.5m-16.5 5.25h16.5\"></path></svg><svg class=\"hidden h-6 w-6\" fill=\"none\" viewBox=\"0 0 24 24\" stroke-width=\"1.5\" stroke=\"currentColor\" aria-hidden=\"true\"><path stroke-linecap=\"round\" stroke-linejoin=\"round\" d=\"M6 18L18 6M6 6l12 12\"></path></svg></button></div><h1 class=\"pinkie-123 asdf asdf asdf asdf asdf\">Pinkie Pie<button class=\"asdf\">test</button></h1>"

[fraschm1998]

Nvm. Seems to be working now. I think I may have just forgotten to clear the build cache.

Thanks!

[lambda-fairy]

Thanks @RedPhoenixQ, looks great so far!

Can you please add a changelog entry as well?

[lambda-fairy]

Thanks @RedPhoenixQ!

Let's merge what we have now. We can address my other comment in a follow-up PR.

[lambda-fairy]

I think string literals, and maybe integers, are enough.

Floating point numbers overlap with class shorthand which also uses .. There's no use case for a single character. And no other part of Maud accepts byte strings.

[RedPhoenixQ]

@lambda-fairy, addressing this issue, to keep ast::name_to_string() as an infallible api (always returning String without errors) I handled all the cases since I didn't see any issue with also handling ByteStr and others so they produce the expected internal string. Current implementation should always produce valid html.

The class shorthand shouldn't be broken since classes starting with numbers are disallowed in CSS so all classes before should still be possible. Also the only time a class starting with a number wouldn't be interpreted as a class would be 123.123 (space followed by numbers with dot and no spaces), but 123 .123, anything.123 and .classname123.123 would still parse as a class shorthand for the class 123.

[lambda-fairy]

Having the interpretation change just by adding a space is the confusing part.

[RedPhoenixQ]

#398 fixes this issue by running the existing literal() function in the parser when encountering a literal, reusing existing error behaviour. I've added Int as an accepted literal, but can revoke that change if you decide that Int shouldn't be allowed.

[RedPhoenixQ]

I found a bug. Literals are now parsed and the try_name() function doesn't see literals, leading to code like html! { div test-123="true" {} } to be generated as <div test- 123="true"></div>