use crate::fs::asyncify;

use std::io;

use std::path::{Path, PathBuf};

/// Returns the canonical, absolute form of a path with all intermediate

/// components normalized and symbolic links resolved.

///

/// This is an async version of [`std::fs::canonicalize`].

///

/// # Platform-specific behavior

///

/// This function currently corresponds to the `realpath` function on Unix

/// and the `CreateFile` and `GetFinalPathNameByHandle` functions on Windows.

/// Note that, this [may change in the future][changes].

///

/// On Windows, this converts the path to use [extended length path][path]

/// syntax, which allows your program to use longer path names, but means you

/// can only join backslash-delimited paths to it, and it may be incompatible

/// with other applications (if passed to the application on the command-line,

/// or written to a file another application may read).

///

/// [changes]: https://doc.rust-lang.org/std/io/index.html#platform-specific-behavior

/// [path]: https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#maxpath

///

/// # Errors

///

/// This function will return an error in the following situations, but is not

/// limited to just these cases:

///

/// * `path` does not exist.

/// * A non-final component in path is not a directory.

///

/// # Examples

///

/// ```no_run

/// use tokio::fs;

/// use std::io;

///

/// #[tokio::main]

/// async fn main() -> io::Result<()> {

///     let path = fs::canonicalize("../a/../foo.txt").await?;

///     Ok(())

/// }

/// ```

pub async fn canonicalize(path: impl AsRef<Path>) -> io::Result<PathBuf> {

    let path = path.as_ref().to_owned();

    asyncify(move || std::fs::canonicalize(path)).await

}