1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136

//! Errorand Result types.
use std::error::Error as StdError;
use std::fmt::{self, Debug, Display};
use std::io;

use serde::de::Visitor;
use serde::ser::{Serialize, Serializer};
use serde::{Deserialize, Deserializer};

pub type Result<T> = std::result::Result<T, Error>;

/// A generic error that represents all the ways a method can fail inside of rexpr::core.
#[derive(Debug)]
#[non_exhaustive]
pub enum Error {
    /// Default Error
    E(String),
}

impl Display for Error {
    // IntellijRust does not understand that [non_exhaustive] applies only for downstream crates
    // noinspection RsMatchCheck
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Error::E(error) => write!(f, "{}", error),
        }
    }
}

impl StdError for Error {}

impl From<io::Error> for Error {
    #[inline]
    fn from(err: io::Error) -> Self {
        Error::from(err.to_string())
    }
}

impl From<&str> for Error {
    fn from(arg: &str) -> Self {
        return Error::E(arg.to_string());
    }
}

impl From<std::string::String> for Error {
    fn from(arg: String) -> Self {
        return Error::E(arg);
    }
}

impl From<&dyn std::error::Error> for Error {
    fn from(arg: &dyn std::error::Error) -> Self {
        return Error::E(arg.to_string());
    }
}

impl From<rexpr::error::Error> for Error {
    fn from(arg: rexpr::error::Error) -> Self {
        return Error::from(arg.to_string());
    }
}

impl Clone for Error {
    fn clone(&self) -> Self {
        Error::from(self.to_string())
    }

    fn clone_from(&mut self, source: &Self) {
        *self = Self::from(source.to_string());
    }
}

// This is what #[derive(Serialize)] would generate.
impl Serialize for Error {
    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        serializer.serialize_str(self.to_string().as_str())
    }
}

struct ErrorVisitor;

impl<'de> Visitor<'de> for ErrorVisitor {
    type Value = String;

    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
        formatter.write_str("a string")
    }

    fn visit_string<E>(self, v: String) -> std::result::Result<Self::Value, E>
    where
        E: std::error::Error,
    {
        Ok(v)
    }

    fn visit_str<E>(self, v: &str) -> std::result::Result<Self::Value, E>
    where
        E: std::error::Error,
    {
        Ok(v.to_string())
    }
}

impl<'de> Deserialize<'de> for Error {
    fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
    where
        D: Deserializer<'de>,
    {
        let r = deserializer.deserialize_string(ErrorVisitor)?;
        return Ok(Error::from(r));
    }
}

pub trait OptionToResult<T> {
    fn to_result(self, error_str: &str) -> Result<T>;
}

impl<T> OptionToResult<T> for Option<T> {
    fn to_result(self, error_str: &str) -> Result<T> {
        if self.is_some() {
            Ok(self.unwrap())
        } else {
            Err(Error::from(error_str))
        }
    }
}

#[test]
fn test_json_error() {
    let e = Error::from("fuck");
    let s = serde_json::to_string(&e).unwrap();
    println!("{}", s.as_str());
}