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    //! is-terminal is a simple utility that answers one question:
    //!
    //! > Is this a terminal?
    //!
    //! A "terminal", also known as a "tty", is an I/O device which may be
    //! interactive and may support color and other special features. This crate
    //! doesn't provide any of those features; it just answers this one question.
    //!
    //! On Unix-family platforms, this is effectively the same as the [`isatty`]
    //! function for testing whether a given stream is a terminal, though it
    //! accepts high-level stream types instead of raw file descriptors.
    //!
    //! On Windows, it uses a variety of techniques to determine whether the
    //! given stream is a terminal.
    //!
    //! # Example
    //!
    //! ```rust
    //! use is_terminal::IsTerminal;
    //!
    //! if std::io::stdout().is_terminal() {
    //!     println!("stdout is a terminal")
    //! }
    //! ```
    //!
    //! [`isatty`]: https://man7.org/linux/man-pages/man3/isatty.3.html

    #![cfg_attr(unix, no_std)]

    #[cfg(not(target_os = "unknown"))]
    use io_lifetimes::AsFilelike;
    #[cfg(windows)]
    use io_lifetimes::BorrowedHandle;
    #[cfg(windows)]
    use windows_sys::Win32::Foundation::HANDLE;
    #[cfg(windows)]
    use windows_sys::Win32::System::Console::STD_HANDLE;

    pub trait IsTerminal {
        /// Returns true if this is a terminal.
        ///
        /// # Example
        ///
        /// ```
        /// use is_terminal::IsTerminal;
        ///
        /// if std::io::stdout().is_terminal() {
        ///     println!("stdout is a terminal")
        /// }
        /// ```
        fn is_terminal(&self) -> bool;
    }

    #[cfg(not(target_os = "unknown"))]
    impl<Stream: AsFilelike> IsTerminal for Stream {
        #[inline]
        fn is_terminal(&self) -> bool {
            #[cfg(any(unix, target_os = "wasi"))]
            {
                rustix::termios::isatty(self)
            }

            #[cfg(target_os = "hermit")]
            {
                hermit_abi::isatty(self.as_filelike().as_fd())
            }

            #[cfg(windows)]
            {
                _is_terminal(self.as_filelike())
            }
        }
    }

    // The Windows implementation here is copied from atty, with #51 and #54
    // applied. The only significant modification is to take a `BorrowedHandle`
    // argument instead of using a `Stream` enum.

    #[cfg(windows)]
    fn _is_terminal(stream: BorrowedHandle<'_>) -> bool {
        use std::os::windows::io::AsRawHandle;
        use windows_sys::Win32::System::Console::GetStdHandle;
        use windows_sys::Win32::System::Console::{
            STD_ERROR_HANDLE as STD_ERROR, STD_INPUT_HANDLE as STD_INPUT,
            STD_OUTPUT_HANDLE as STD_OUTPUT,
        };

        let (fd, others) = unsafe {
            if stream.as_raw_handle() == GetStdHandle(STD_INPUT) as _ {
                (STD_INPUT, [STD_ERROR, STD_OUTPUT])
            } else if stream.as_raw_handle() == GetStdHandle(STD_OUTPUT) as _ {
                (STD_OUTPUT, [STD_INPUT, STD_ERROR])
            } else if stream.as_raw_handle() == GetStdHandle(STD_ERROR) as _ {
                (STD_ERROR, [STD_INPUT, STD_OUTPUT])
            } else {
                return false;
            }
        };
        if unsafe { console_on_any(&[fd]) } {
            // False positives aren't possible. If we got a console then
            // we definitely have a tty on stdin.
            return true;
        }

        // At this point, we *could* have a false negative. We can determine that
        // this is true negative if we can detect the presence of a console on
        // any of the other streams. If another stream has a console, then we know
        // we're in a Windows console and can therefore trust the negative.
        if unsafe { console_on_any(&others) } {
            return false;
        }

        // Otherwise, we fall back to a very strange msys hack to see if we can
        // sneakily detect the presence of a tty.
        // Safety: function has no invariants. an invalid handle id will cause
        // GetFileInformationByHandleEx to return an error.
        let handle = unsafe { GetStdHandle(fd) };
        unsafe { msys_tty_on(handle) }
    }

    /// Returns true if any of the given fds are on a console.
    #[cfg(windows)]
    unsafe fn console_on_any(fds: &[STD_HANDLE]) -> bool {
        use windows_sys::Win32::System::Console::{GetConsoleMode, GetStdHandle};

        for &fd in fds {
            let mut out = 0;
            let handle = GetStdHandle(fd);
            if GetConsoleMode(handle, &mut out) != 0 {
                return true;
            }
        }
        false
    }

    /// Returns true if there is an MSYS tty on the given handle.
    #[cfg(windows)]
    unsafe fn msys_tty_on(handle: HANDLE) -> bool {
        use std::ffi::c_void;
        use windows_sys::Win32::{
            Foundation::MAX_PATH,
            Storage::FileSystem::{FileNameInfo, GetFileInformationByHandleEx},
        };

        /// Mirrors windows_sys::Win32::Storage::FileSystem::FILE_NAME_INFO, giving
        /// it a fixed length that we can stack allocate
        #[repr(C)]
        #[allow(non_snake_case)]
        struct FILE_NAME_INFO {
            FileNameLength: u32,
            FileName: [u16; MAX_PATH as usize],
        }
        let mut name_info = FILE_NAME_INFO {
            FileNameLength: 0,
            FileName: [0; MAX_PATH as usize],
        };
        // Safety: buffer length is fixed.
        let res = GetFileInformationByHandleEx(
            handle,
            FileNameInfo,
            &mut name_info as *mut _ as *mut c_void,
            std::mem::size_of::<FILE_NAME_INFO>() as u32,
        );
        if res == 0 {
            return false;
        }

        let s = &name_info.FileName[..name_info.FileNameLength as usize / 2];
        let name = String::from_utf16_lossy(s);
        // This checks whether 'pty' exists in the file name, which indicates that
        // a pseudo-terminal is attached. To mitigate against false positives
        // (e.g., an actual file name that contains 'pty'), we also require that
        // either the strings 'msys-' or 'cygwin-' are in the file name as well.)
        let is_msys = name.contains("msys-") || name.contains("cygwin-");
        let is_pty = name.contains("-pty");
        is_msys && is_pty
    }

    #[cfg(target_os = "unknown")]
    impl IsTerminal for std::io::Stdin {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl IsTerminal for std::io::Stdout {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl IsTerminal for std::io::Stderr {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl<'a> IsTerminal for std::io::StdinLock<'a> {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl<'a> IsTerminal for std::io::StdoutLock<'a> {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl<'a> IsTerminal for std::io::StderrLock<'a> {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl<'a> IsTerminal for std::fs::File {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl IsTerminal for std::process::ChildStdin {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl IsTerminal for std::process::ChildStdout {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(target_os = "unknown")]
    impl IsTerminal for std::process::ChildStderr {
        #[inline]
        fn is_terminal(&self) -> bool {
            false
        }
    }

    #[cfg(test)]
    mod tests {
        #[cfg(not(target_os = "unknown"))]
        use super::IsTerminal;

        #[test]
        #[cfg(windows)]
        fn stdin() {
            assert_eq!(
                atty::is(atty::Stream::Stdin),
                std::io::stdin().is_terminal()
            )
        }

        #[test]
        #[cfg(windows)]
        fn stdout() {
            assert_eq!(
                atty::is(atty::Stream::Stdout),
                std::io::stdout().is_terminal()
            )
        }

        #[test]
        #[cfg(windows)]
        fn stderr() {
            assert_eq!(
                atty::is(atty::Stream::Stderr),
                std::io::stderr().is_terminal()
            )
        }

        #[test]
        #[cfg(any(unix, target_os = "wasi"))]
        fn stdin() {
            unsafe {
                assert_eq!(
                    atty::is(atty::Stream::Stdin),
                    rustix::io::stdin().is_terminal()
                )
            }
        }

        #[test]
        #[cfg(any(unix, target_os = "wasi"))]
        fn stdout() {
            unsafe {
                assert_eq!(
                    atty::is(atty::Stream::Stdout),
                    rustix::io::stdout().is_terminal()
                )
            }
        }

        #[test]
        #[cfg(any(unix, target_os = "wasi"))]
        fn stderr() {
            unsafe {
                assert_eq!(
                    atty::is(atty::Stream::Stderr),
                    rustix::io::stderr().is_terminal()
                )
            }
        }

        #[test]
        #[cfg(any(unix, target_os = "wasi"))]
        fn stdin_vs_libc() {
            unsafe {
                assert_eq!(
                    libc::isatty(libc::STDIN_FILENO) != 0,
                    rustix::io::stdin().is_terminal()
                )
            }
        }

        #[test]
        #[cfg(any(unix, target_os = "wasi"))]
        fn stdout_vs_libc() {
            unsafe {
                assert_eq!(
                    libc::isatty(libc::STDOUT_FILENO) != 0,
                    rustix::io::stdout().is_terminal()
                )
            }
        }

        #[test]
        #[cfg(any(unix, target_os = "wasi"))]
        fn stderr_vs_libc() {
            unsafe {
                assert_eq!(
                    libc::isatty(libc::STDERR_FILENO) != 0,
                    rustix::io::stderr().is_terminal()
                )
            }
        }

        // Verify that the msys_tty_on function works with long path.
        #[test]
        #[cfg(windows)]
        fn msys_tty_on_path_length() {
            use std::{fs::File, os::windows::io::AsRawHandle};
            use windows_sys::Win32::Foundation::MAX_PATH;

            let dir = tempfile::tempdir().expect("Unable to create temporary directory");
            let file_path = dir.path().join("ten_chars_".repeat(25));
            // Ensure that the path is longer than MAX_PATH.
            assert!(file_path.to_string_lossy().len() > MAX_PATH as usize);
            let file = File::create(file_path).expect("Unable to create file");

            assert!(!unsafe { crate::msys_tty_on(file.as_raw_handle() as isize) });
        }
    }