vars and consts grouped

[domgreen]

Ideally, it would be best to group all vars/consts that are defined close to each other.

Example:

bad:

var a = "a"
var b = "b"

good:

var (
	a = "a"
	b = "b"
)

[mvdan]

Thanks! I wonder if this would be too noisy to do for two lines, as we double the amount of source lines. But I'd definitely agree that this should happen for three or more contiguous lines.

[andrewrynhard]

I think I'd still prefer it with only 2 or more. Maybe that could be configurable?

[mvdan]

I'm afraid configuration is near impossible; if we added any flags, config files, or env vars, then this tool would no longer be a drop-in replacement for gofmt.

I also want this tool to be a "gofmt with some extras", so it should work out of the box without any extra configuration needed. If anything requires the user to make a decision, it's not worth doing in a formatting tool that's opinionated.

Having said this, we could make different decisions based on the context. For example, I think globals should be grouped if there are at least 2. Local variables could have a higher threshold (like 3) if 2 is too noisy.