Code becomes very unclear on mix of for loop and iterator combinators

[masklinn]

The code is basically a longer version of Clippy's manual flatten example, with the iterable inline. If the for line is long enough:

    let an_item = None;
    let an_other_item = None;

    for mut a_nice_declarative_name in [
        Some("a value"),
        an_item,
        Some("an other value"),
        an_other_item,
        Some("more"),
        Some("stuff"),
        Some("again"),
    ].into_iter().flatten() {
        println!("{}", a_nice_declarative_name);
    }

gets reformatted to

    for mut a_nice_declarative_name in [
        Some("a value"),
        an_item,
        Some("an other value"),
        an_other_item,
        Some("more"),
        Some("stuff"),
        Some("again"),
    ]
    .into_iter()
    .flatten()
    {
        println!("{}", a_nice_declarative_name);
    }

the lone block brackets, and methods floating in the middle, feel and read very odd. I actually spent a few seconds wondering why I had put the actual code (whose body is quite a bit more complicated) inside its own block after rustfmt ran on it, interpreting it as a sub-scope rather than what it is (a loop body).

[calebcartwright]

Thanks for sharing your perspective but I'm going to close because this is correct, expected formatting per the governing Style Guide.

You may be interested in reviewing issues like #4306 (comment) which outlines some (non-default) options we're exploring that would give you the flexibility to maintain the type of formatting you'd authored