feat: new minify-js arg for templ generate

[garrettladley]

completed version of @cornejongs draft pr here

handled templ Component() { <script ...>...</script> } and script Component() { ... } cases.

i've tested this locally by comparing outputs when -minify-js=true vs -minify-js=false with go run ./cmd/templ generate -include-version=false -f [file] -minify-js=[bool]

do you have any ideas / starting points on how to write tests for an argument to templ generate? i didn't see any other examples in the project

[garrettladley]

also, does anyone know how to fix the CI/build step? running into the following error:
generator/generator.go:20:2: cannot find module providing package github.com/tdewolff/minify/v2: import lookup disabled by -mod=vendor

[cornejong]

Honestly, i kinda forgot that i started working on that 😅
Took a look at it yesterday and today, and finished my implementation #772 .
It differs from yours in a few ways:

• Add CSS minification as well (why not?) --minify-css
• Script tag src attribute check. No need to run the minifier on tags that load in scripts remotely.
• Script tag type attribute check. Not all script tags neccesarily contain javascript / minifiable contents.

The attribute checks are build on the assumption that those attribute are defined using a constant/static attribute declaration (not using a spread or conditional declaration). Mostly because of the way those are implemented right now. there is no easy check if those attributes are present/set at generation. I'll leave it up to @a-h to decide if that's acceptable or not. Might look into making that a bit more bomb proof in the future. For now it seems to work quite well.

Any script tag content type that is supported by the minifier (tdewolff/minify/v2 ) will be minified. including Json content.

Css minification is only applied to <style> tags. The css SomeClass() { ... } syntax already seemd minified.