Support .templ files with Go auto complete etc

[Req23]

When trying to work on a .tmpl file in a Go project I lose auto completion on structs/packages etc. Also the imports are not found resulting in a warning/error in VSCode.

example:
/views/login/index.templ

package login

import (
	"app/models"
)

templ LoginForm(errors models.LoginError) {
	<form>
            ***
	<input type="password" name="password" required placeholder="Password" class="input input-bordered w-full"/>
	if len(errors.Password) > 0 {
	    <span class="text-sm text-error">
	       { errors.Password }
            </span>
	}
	 ***

errors.Password (the errors struct has multiple items, this does not do code auto completion or suggestions)
The package error shows: No packages found for open file /views/login/index.templ even though this is incorrect as the package is valid.

I would like the IDE in VSCode to be able to handle all the auto completions etc as if it was a .go file.

[Hyang-Ah Hana Kim]

I guess you are using a-h/templ. Isn't the templ extension able to handle auto-complete?

https://templ.guide/commands-and-tools/ide-support/#visual-studio-code

cc @a-h

[Req23]

Yeah I am using a-h/templ along with the vscode-go extension. I followed the guide for VSC with vscode-go + a-h/templ. I thought maybe the go side of it was responsible for the imports, auto completes, etc.

[Req23]

Auto completion is working with:
gopls v. 0.15.3
and
a-h/templ from @main

The newest version of gopls and templ didn't seem to work together. Just letting you know what I found.

[Hyang-Ah Hana Kim]

Thanks @Req23. That's helpful!

I don't know the details on how templ LSP server proxies gopls.
gopls v0.16.0+ started to use InsertReplaceEdits if the client sets the capability. (https://github.com/golang/tools/blob/master/gopls/internal/protocol/tsprotocol.go#L1024).
If the templ LSP relies on github.com/a-h/protocol, I see that it does not handle InsertReplaceEdits type yet
(https://github.com/a-h/protocol/blob/b4eec67c1c223e5a747d39f3d07f62d25236aa4a/language.go#L260).

I think the templ LSP server needs to either

1. update the protocol to support InsertReplaceEdits, or
2. adjust the client capability so InsertReplaceSupport is unset before forwarding the capability.

Can you please open an issue to the a-h/templ repo? Thanks!