macro_rules! create_mock_struct {
(@create_expect_methods) => { ... };
(@create_expect_methods $name:ident($key:expr) $inputs:ty => $output:ty; $($tail:tt)*) => { ... };
(@create_expect_methods $name:ident($key:expr) $inputs:ty; $($tail:tt)*) => { ... };
(@create_expect_methods $name:ident($key:expr); $($tail:tt)*) => { ... };
(struct $name:ident: {
$($methods:tt)*
}) => { ... };
}