#[macro_export]
macro_rules! assert_variant {
    ($e:path: $($v:ident),+ $(,)?) => {
        #[allow(unused_imports)]
        const _: fn() = || {
            use $e as AnEnum;
            $(
                use AnEnum::$v as _;
            )+
        };
    };
}

pub mod tests {

    #[allow(dead_code)]
    pub enum Thing {
        A,
        B { x: () },
        C(()),
        AnEnum,
    }

    #[test]
    fn should_compile() {
        assert_variant!(Thing: A);
        assert_variant!(Thing: B);
        assert_variant!(Thing: C);

        assert_variant!(self::Thing: AnEnum, A, B, C);
    }

    /// # Single missing variant
    ///
    /// ```fail_compile
    /// use playground::assert_variant;
    /// use playground::tests::Thing;
    ///
    /// assert_variant!(Thing: D);
    /// ```
    ///
    /// # Multiple missing variants
    ///
    /// ```fail_compile
    /// use playground::assert_variant;
    /// use playground::tests::Thing;
    ///
    /// assert_variant!(Thing: D, E, F);
    /// ```
    ///
    /// # Multiple missing variants with a single existing variant.
    ///
    /// ```fail_compile
    /// use playground::assert_variant;
    /// use playground::tests::Thing;
    ///
    /// assert_variant!(Thing: A, D, E, F);
    /// ```
    ///
    /// # Missing variant with path to Enum
    ///
    /// ```fail_compile
    /// use playground::assert_variant;
    /// use playground::tests::Thing;
    ///
    /// assert_variant!(playground::tests::Thing: D, AnEnum);
    /// ```
    #[allow(dead_code)]
    fn fail_compile() {}
}