I'd like to check enums with fields in tests while ignoring the actual value of the fields for now.

Consider the following example:

```
enum MyEnum {
    WithoutFields,
    WithFields { field: String },
}

fn return_with_fields() -> MyEnum {
    MyEnum::WithFields {
        field: "some string".into(),
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn example() {
        assert_eq!(return_with_fields(), MyEnum::WithFields {..});
    }
}

```

[playground](https://play.rust-lang.org/?gist=e9e9726c146ecb20ea837f15e77e9410&version=stable&mode=debug&edition=2015)

I'd like to use `assert_eq!` here, but the compiler tells me:

```none
error: expected expression, found `}`
  --> src/lib.rs:18:64
   |
18 |         assert_eq!(return_with_fields(), MyEnum::WithFields {..});
   |                                                                ^ expected expression

```

This is similar to [Why do I get an error when pattern matching a struct-like enum variant with fields?](https://stackoverflow.com/questions/50775023/why-do-i-get-an-error-when-pattern-matching-a-struct-like-enum-variant-with-fiel), but the solution does not apply in my case.

Of course, I can use `match` and do it myself, but being able to use `assert_eq!` would be less work.