extension: do not classify '.tmpl' as 'gotmpl' by default

[thernstig]

Is your feature request related to a problem? Please describe.
Consider not activating the extension until a go file is open or a user explicitly requests (command/setting). In the latest version of the exention we get this (which we did not do before):

Failed to find the "go" binary in either GOROOT() or PATH(/home/tobias/.vscode-server/bin/e8653663e8840adaf45af01eab5c627a5af81807/bin/remote-cli:/home/tobias/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/usr/lib/wsl/lib:/mnt/c/WINDOWS/system32:/mnt/c/WINDOWS:/mnt/c/WINDOWS/System32/Wbem:/mnt/c/WINDOWS/System32/WindowsPowerShell/v1.0/:/mnt/c/WINDOWS/System32/OpenSSH/:/mnt/c/Program Files/WinMerge:/mnt/c/Program Files/Git/cmd:/mnt/c/Users/siniz/AppData/Local/Microsoft/WindowsApps:/mnt/c/Users/siniz/AppData/Local/Programs/Microsoft VS Code/bin:/snap/bin). Check PATH, or Install Go and reload the window. If PATH isn't what you expected, see https://github.com/golang/vscode-go/issues/971

Describe the solution you'd like
Do not invoke anything from the extension until a Go file, or any file type that the extension is registered with, is opened.

Describe alternatives you've considered
None

Additional context
This worked before. It has regressed in the latest version. See these previously, solved topics:
#2164
#3038

[hyangah]

This extension is meant to get activated only when a go-related file is open or Go debugging is asked.

https://github.com/golang/vscode-go/blob/master/extension/package.json#L97-L103

The welcome page event is suspicious, but this activation event setting didn't change for quite some time.

@thernstig Can you please check the Extension Host output log and see what triggered golang.go extension in your env?

[thernstig]

@hyangah I cannot get it to replicate now. But I do not have any repositories with Go files, and even if I did I have not opened any Golang files. I am going to close this issue, but will re-open if I see this again with the output from the Extension Host log.

[thernstig]

@hyangah I am reopening this temporarily to ask for consultation if this should change or not. I now found out why I see the error, and also understand why.

I am opening a .tmpl file.

As can be seen here, any .tmpl file is considered a gotmpl language identifier:

https://github.com/golang/vscode-go/blob/9eedcfc824ef099d7dbef7aee567d501dde917f8/extension/package.json#L161C1-L170C8

The problem here is, there are multiple languages that use .tmpl as their extension. There is no conflict resolution done when this happens, see microsoft/vscode-docs#2862. It most likely chose the extension that come first in alphabetical order.

Question

Should this extension in reality contribute the .tmpl file as it is so ambiguous and can be used by other languages?

I also wrote microsoft/vscode#233894

[hyangah]

Thanks @thernstig
I repurposed this issue to discuss on .tmpl.

vscode-go/extension/package.json

Line 164 in b770fb8

".tmpl",

Actually, .tmpl was the file extension first mentioned in the Go template support FR. #609 so I think changing this will affect existing users.

You can configure your setting

    "files.associations": {
        "*.tmpl": "plaintext"
    }

(This will prevent from activating the Go extension just because you opened .tmpl file...)

or by interactively selecting the language by clicking the language status bar on the bottom right.

[thernstig]

@hyangah it is possible for me to reconfigure the file association, but I think the core of the problem is microsoft/vscode#233894

Maybe you can help upvote that? I am closing this issue again, as I understand the rationale why you have it as you do. It is just hard for many users who work in multiple languages, where various files might have .tmpl.