Fix: giscus.html fails when country code is specified.

[dogweather]

The problem is that the Giscus API fails when given data-lang of something like de-DE:

This fix uses just the language tag, not the whole language code: https://gohugo.io/methods/site/language/#methods

With this fix:

(live at https://forkful.ai/de/kotlin/good-coding-practices/ )

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[imfing]

Thanks for the PR. It makes sense.

I checked the list of available locales on giscus and noticed that zh-CN and zh-TW use mixed casing.
With this change, the giscus will now use the lowercase zh-cn in our example site, which can be seen here:

hextra/exampleSite/hugo.yaml

Line 25 in be7e0d3

zh-cn:

Could you try changing zh-cn to zh-CN in the above link to see if everything still works correctly?

[dogweather]

Huh, will do. I'm guessing we need to make a special case for those. And yep, currently on my site, using just zh, it's broken.

[dogweather]

With this change, the giscus will now use the lowercase zh-cn in our example site, which can be seen here:

hextra/exampleSite/hugo.yaml

Line 25 in be7e0d3

zh-cn:

Could you try changing zh-cn to zh-CN in the above link to see if everything still works correctly?

I'm confused, sorry. With my change, it will just use the first two letters of the code. Here's my debug output I verified this with:

".Language.Lang": "zh"
".Language.LanguageCode": "zh-CN"

And that currently breaks because giscus doesn't have i18n support for simple zh.

[dogweather]

I added special handling for Chinese. I tested it with:

languageCode: zh

languageCode: zh-cn

languageCode: zh-CN

languageCode: zh-tw

languageCode: zh-TW

[imfing]

Awesome,appreciate it 👍
I was asking because of this issue #231

Will review it later today

[imfing]

In this case, $giscus_lang could also be zh-cn, so it's better to use hasPrefix instead of eq.

[imfing]

Should we just inline this $default_chinese, or move it inside the if block?