rust/tests/target/configs/format_macro_matchers/true.rs

// rustfmt-format_macro_matchers: true

macro_rules! foo {
    ($a:ident : $b:ty) => {
        $a(42): $b;
    };
    ($a:ident $b:ident $c:ident) => {
        $a = $b + $c;
    };
}