imag/lib/core/libimagerror/src/exit.rs

//
// imag - the personal information management suite for the commandline
// Copyright (C) 2015-2019 the imag contributors
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; version
// 2.1 of the License.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
//

use std::error::Error;
use std::fmt::{Formatter, Display};

#[derive(Debug)]
pub struct ExitCode(i32);

impl From<i32> for ExitCode {
    fn from(i: i32) -> ExitCode {
        ExitCode(i)
    }
}

impl ExitCode {
    pub fn code(self) -> i32 {
        self.0
    }
}

impl Display for ExitCode {
     fn fmt(&self, f: &mut Formatter) -> Result<(), std::fmt::Error> {
         write!(f, "ExitCode {}", self.0)
     }
}

impl Error for ExitCode {
    fn description(&self) -> &str {
        "ExitCode"
    }

    fn cause(&self) -> Option<&dyn Error> {
        None
    }

    fn source(&self) -> Option<&(dyn Error + 'static)> {
        None
    }
}

pub trait ExitUnwrap<T> {
    fn unwrap_or_exit(self) -> T;
}

impl<T, E: Into<ExitCode>> ExitUnwrap<T> for Result<T, E> {
    fn unwrap_or_exit(self) -> T {
        self.map_err(Into::into).unwrap_or_else(|e| ::std::process::exit(e.0))
    }
}