gofumpt -w foo.go
cmp foo.go foo.go.golden

gofumpt -d foo.go.golden
! stdout .

-- foo.go --
package p

var global = x

func f() {
	var local = x
	var local2, local3 = x, y

	var onlyType T

	var typeAndVar T = x

	var _ = unused

	var (
		aligned = x
		vars    = y
		here    = y
	)
}
-- foo.go.golden --
package p

var global = x

func f() {
	local := x
	local2, local3 := x, y

	var onlyType T

	var typeAndVar T = x

	_ = unused

	var (
		aligned = x
		vars    = y
		here    = y
	)
}