easy_err/

err.rs

use std::{error, fmt, fs::OpenOptions, io::{self, Write}, path::Path};

use colored::Colorize;
pub use chrono::{DateTime, Local};


/// 用于统一错误的枚举
/// 
/// # Examples
/// ``` 
/// let err = easy_err::Error::custom("Here is a error.");
/// err.report();
/// ```
#[derive(Debug)]
pub enum Error {
	/// 用于包装已经实现Error Trait的结构体或枚举
	Basic(DateTime<Local>, Box<dyn error::Error>),
	/// 用于报告用户自定义的错误信息
	Custom(DateTime<Local>, String)
}

impl Error {
	/// 获取错误发生的时间
	/// 
	/// # Example
	/// ```
	/// let time = easy_err::Error::custom("Here is a custom error.").time();
	/// println!("{}", time);
	/// ```
	pub fn time(&self) -> DateTime<Local> {
		match self {
			Self::Basic(time, _) => *time,
			Self::Custom(time, _) => *time
		}
	}

	/// 产生一个basic变体
	/// 
	/// # Examples
	/// ```
	/// let file = std::fs::File::open("An obvious mistake.").or_else(|err|{Err(easy_err::Error::basic(err))});
	/// match file {
	/// 	Ok(_) => println!("Ok!"),
	/// 	Err(err) => {err.report();}
	/// }
	/// ```
	pub fn basic(err: impl error::Error + 'static) -> Error {
		Error::Basic(Local::now(), Box::new(err))
	}

	/// 产生一个custom变体
	/// 
	/// # Examples
	/// ```
	/// let custom_err = easy_err::Error::custom("Here is a error.");
	/// custom_err.report();
	/// ```
	pub fn custom<S>(msg: S) -> Error where S:ToString{
		Error::Custom(Local::now(), msg.to_string())
	}

	/// 在标准错误流中输出一条报告信息
	/// 
	/// # Examples
	/// ```
	/// let custom_err = easy_err::Error::custom("Here is a error.");
	/// custom_err.report();
	/// // output:
	/// // error:
	/// //     time: <ErrorTime>
	/// //      msg: 'Here is a error.'
	/// ```
	pub fn report(&self) -> &Self {
		eprintln!("{}: {}", "error".red().bold(), self);
		self
	}

	/// 引发 panic!() 宏
	/// 
	/// # Examples
	/// ```
	/// let custom_err = easy_err::Error::custom("Here is a error.");
	/// custom_err.panic(); 
	/// // output:
	/// // error:
	/// //     time: <ErrorTime>
	/// //      msg: 'Here is a error.'
	/// ```
	pub fn panic(&self){
		panic!("{}", self);
	}

	/// 将报告信息输出至文件
	/// 
	/// # Params
	/// - path: 任何可以转换为 Path 的值
	/// 
	/// # Examples
	/// ```
	/// let custom_err = easy_err::Error::custom("Here is a error.");
	/// custom_err.log_to("./log.txt");
	/// ```
	pub fn log_to<P>(&self, path: P) -> &Self where P: AsRef<Path> {
		match OpenOptions::new().create(true).append(true).open(path) {
			Ok(mut file) => {
				if let Err(err) = writeln!(file, "error:{}", self) {
					Error::basic(err).report();
				}
			}
			Err(err) => {Error::basic(err).report();}
		}
		self
	}
}

impl fmt::Display for Error {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
		match self {
			Self::Basic(time, err) => write!(f, "\n\ttime: {}\n\t msg: {}\n", time, err),
			Self::Custom(time, msg) => write!(f, "\n\ttime: {}\n\t msg: {}\n", time, msg)
		}
	}
}

impl error::Error for Error {
	fn source(&self) -> Option<&(dyn error::Error + 'static)> {
		match self {
			Self::Basic(.., err) => Some(err.as_ref()),
			Self::Custom(..) => None
		}
	}
}

impl From<io::Error> for Error {
	fn from(value: io::Error) -> Self {
		Self::basic(value)
	}
}

impl From<fmt::Error> for Error {
	fn from(value: fmt::Error) -> Self {
		Self::basic(value)
	}
}

/// 用于方便地将Result<T, Error>当作Error处理
/// 
/// # Tips
/// - 不建议为别的结构体或枚举实现此Trait，因为我自己还没完全搞清楚这个地方该怎么弄，这暂且还是一个实验性功能
/// 
/// # Example
/// ```
/// use std::fs;
/// use easy_err::{Error, ErrResult};
/// 
/// fn test() -> Result<(), Error> {
/// 	fs::File::open("An obvious mistake.")?;
/// 	Ok(())
/// }
/// 
/// test().panic();
/// ```
pub trait ErrResult<T> {
	fn panic(self: Self) -> T;
}

impl<T> ErrResult<T> for Result<T, Error> {
	fn panic(self) -> T {
		match self {
			Ok(t) => t,
			Err(err) => panic!("{}", err.to_string())
		}
	}
}