fix: use correct syntax for boolean attributes

[pimlie]

Another issue I noticed by running html-minifier (I am adding an itemscope).

Interestingly, it seems the typeof undefined check will never be true (at least with ssr). I wasnt able to give my attribute an undefined value to only print the attribute tag (edit: not sure where but in my Nuxt project somewhere between nuxt:getNuxtConfig and vue-meta:getMetaInfo the attributes with undefined values are completely stripped).

There are quite a bit of attributes which should never be used on a html/body, but for the sake of completeness I still included them. Maybe in a next major version we could just do a type check on data[attr] === true, but that again could result in invalid html when passing custom attributes so not sure what would be best

[codecov-io]

Codecov Report

Merging #317 into master will decrease coverage by 0.15%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master     #317      +/-   ##
==========================================
- Coverage   40.89%   40.74%   -0.16%     
==========================================
  Files          19       19              
  Lines         269      270       +1     
==========================================
  Hits          110      110              
- Misses        159      160       +1

Impacted Files	Coverage Δ
src/server/generators/attrsGenerator.js	0% <0%> (ø)	⬆️

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[TheAlexLichter]

@pimlie Could you add a test for that? ☺️

[pimlie]

@manniL with the state of the tests in general I'd prefer not to actually. There are no tests yet which validate really the generated html and I dont think its worth my time to add it if vue-meta gets deprecated in its current form because of nuxt/rfcs # 19. Or is that rfc now deprecated since vue-meta is part the nuxt project?

[TheAlexLichter]

@pimlie I don't think vue-meta nor the RFC will be deprecated. Whether we will use vue-meta to implement that RFC or not isn't clear yet but there are a lot of other projects "depending" on vue-meta ☺️

[TheAlexLichter]

@pimlie Should I merge that after the refactor? ☺️

[pimlie]

I think its best to close this one, we will find another way 🚡