You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: identity.rs
    path of file: ./repos/windows-rs/crates/tests/implement/tests
    
    the code of the file until where you have to start completion: #![allow(non_snake_case)]

use windows::{core::*, Foundation::*};

static mut COUNTER: isize = 0;

#[implement(IStringable, IClosable)]
struct Test(String);

impl Test {
    fn new(value: &str) -> Self {
        unsafe {
            COUNTER += 1;
        }
        Self(value.to_string())
    }
}

impl Drop for Test {
    fn drop(&mut self) {
        unsafe {
            COUNTER -= 1;
        }
    }
}

impl IStringable_Impl for Test {
    fn ToString(&self) -> Result<HSTRING> {
        Ok(self.0.as_str().into())
    }
}

impl IClosable_Impl for Test {
    fn Close(&self) -> Result<()> {
        Ok(())
    }
}

#[test]
fn identity() -> Result<()> {
    unsafe {
        assert_eq!(COUNTER, 0);
        {
            let a: IStringable = Test::new("test").into();
           
    
fn identity() -> Result<()> {
    unsafe {
        assert_eq!(COUNTER, 0);
        {
            let a: IStringable = Test::new("test").into();
            assert!(a.ToString()? == "test");

            let b: IClosable = a.cast()?;
            b.Close()?;

            let c: IUnknown = b.cast()?;

            let d: IInspectable = c.cast()?;

            assert!(a == d.cast()?);
        }
        {
            let a: IUnknown = Test::new("test").into();
            let b: IClosable = a.cast()?;
            let c: IStringable = b.cast()?;
            assert!(c.ToString()? == "test");
        }
        {
            let a: IInspectable = Test::new("test").into();
            let b: IStringable = a.cast()?;
            assert!(b.ToString()? == "test");
        }
        {
            let a: IInspectable = Test::new("test").into();
            assert_eq!(a.GetRuntimeClassName()?, "Windows.Foundation.IStringable");

            let b: IStringable = a.cast()?;
            let c: &IInspectable = &b.cast()?;
            assert_eq!(c.GetRuntimeClassName()?, "Windows.Foundation.IStringable");

            let d: IClosable = a.cast()?;
            let e: &IInspectable = (&d).into();
            assert_eq!(e.GetRuntimeClassName()?, "Windows.Foundation.IClosable");

            let f: IInspectable = e.cast()?;
            assert_eq!(f.GetRuntimeClassName()?, "Windows.Foundation.IStringable");
        }
        assert_eq!(COUNTER, 0);
        Ok(())
    }
}