No empty lines before a simple error check not working

[ftamhar]

If my code like this

package main

import "fmt"

func main() {
    var i int
    var err error
    i, err = fmt.Println("hello world")

    if err != nil {
        panic(err)
    }

    fmt.Println(i, err)
}

and I run gofumpt -l -w ., my expected result is like this

package main

import "fmt"

func main() {
    var i int
    var err error
    i, err = fmt.Println("hello world"
    if err != nil {
        panic(err)
    }

    fmt.Println(i, err)
}

but the result is like the first code snippet.

How do I achieve the results I expect?

[flan6]

I noticed that sometimes it does not work too.

[mvdan]

This check only triggers if the previous line follows the , err := pattern - note how it requires the token :=, it doesn't accept =. I agree that that's an unnecessary restriction, and we should make the formatter slightly more aggressive.