MeiliSearch/meilidb-core/src/number.rs

use std::num::{ParseIntError, ParseFloatError};
use std::str::FromStr;
use std::fmt;

use ordered_float::OrderedFloat;
use serde::{Serialize, Deserialize};

#[derive(Serialize, Deserialize)]
#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum Number {
    Unsigned(u64),
    Signed(i64),
    Float(OrderedFloat<f64>),
}

impl FromStr for Number {
    type Err = ParseNumberError;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let uint_error = match u64::from_str(s) {
            Ok(unsigned) => return Ok(Number::Unsigned(unsigned)),
            Err(error) => error,
        };

        let int_error = match i64::from_str(s) {
            Ok(signed) => return Ok(Number::Signed(signed)),
            Err(error) => error,
        };

        let float_error = match f64::from_str(s) {
            Ok(float) => return Ok(Number::Float(OrderedFloat(float))),
            Err(error) => error,
        };

        Err(ParseNumberError { uint_error, int_error, float_error })
    }
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ParseNumberError {
    uint_error: ParseIntError,
    int_error: ParseIntError,
    float_error: ParseFloatError,
}

impl fmt::Display for ParseNumberError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        if self.uint_error == self.int_error {
            write!(f, "can not parse number: {}, {}", self.uint_error, self.float_error)
        } else {
            write!(f, "can not parse number: {}, {}, {}",
                self.uint_error, self.int_error, self.float_error)
        }
    }
}