go: Add runnables

[mrnugget]

This adds support for runnables to Go.

It adds the following tasks:

• go test $ZED_GO_PACKAGE -run $ZED_SYMBOL
• go test $ZED_GO_PACKAGE
• go test ./...
• go run $ZED_GO_PACKAGE if it has a main function

Release Notes:

• Added built-in Go runnables and tasks that allow users to run Go test functions, test packages, or run main functions.

Demo:

screenshot-2024-05-22-07.06.28.mp4

screenshot-2024-05-22-07.17.04.mp4

[mrnugget]

@osiewicz I assume it's not possible yet, but: is it possible for this task to only show up if there is something tagged with go-main? I only add the tag in the runnables.scm if there is a func main(), but this shows up everywhere. I don't think it's a blocker, because you can run packages without being on the main function, but still curious.

[joefitzgerald]

This looks very useful! However, my shell is fish, and running a test doesn't work:

fish: Variables cannot be bracketed. In fish, please use {$ZED_CUSTOM_GO_P…}.
go test ${ZED_CUSTOM_GO_PACKAGE} -run $ZED_SYMBOL
         ^

⏵ Task `go test ./http/middleware -run TestCacheBuster` finished with non-zero error code: 127
⏵ Command: '/opt/homebrew/bin/fish -i -c `go test ./http/middleware -run TestCacheBuster`'

[osiewicz]

Hey Joe,
Yeah, that's related to #10964 - we need a way to pin execution of a task to a particular shell in order for fish and others to play nicely with language tasks

[sunliang711]

Thanks for your hard working, could you tell me how to add custom flags to 'go test', eg: 'go test -v -count=1 ...'