cmd/gofmt: Inconsistent space before open curly brace

[dsnet]

Using go1.5beta3.

This is obviously subjective, so feel free to close.

When struct definition is placed on a single line, it removes the space between the struct and {.

type Foo struct {
    int
}

type Bar struct{ int }

When an anonymous struct is used and instantiated, it lacks a space before the { as well.

for _, x := range []struct {
    b bool
    n int
}{ // There is NO space between '}' and '{'
    {false, 0},
    {true, 2},
    {false, 16},
} { // There IS a space between '}' and '{'
    fmt.Println(x)
}

[griesemer]

This is probably not going to change, at least for the current gofmt, since it just produces needless churn in many files.

Leaving open as a reminder for a future version of gofmt.

[ianlancetaylor]

The second example in the original message is a composite literal. Composite literals never have a space between the type and the initializer. Then the space between the braces before the body is always there as well.

So the question is whether there should be a difference when the struct definition is all on one line. @griesemer suggests that there should always be a space except when the struct has no fields, in which case it should be simply struct{}. Similarly for an interface type with no methods.

This doesn't have to be a go2 issue, moving to unplanned.