MeiliSearch/meilisearch-core/src/number.rs
2019-11-26 11:12:30 +01:00

111 lines
2.9 KiB
Rust

use std::cmp::Ordering;
use std::fmt;
use std::num::{ParseFloatError, ParseIntError};
use std::str::FromStr;
use ordered_float::OrderedFloat;
use serde::{Deserialize, Serialize};
#[derive(Serialize, Deserialize, Debug, Copy, Clone, 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,
})
}
}
impl PartialEq for Number {
fn eq(&self, other: &Number) -> bool {
self.cmp(other) == Ordering::Equal
}
}
impl Eq for Number {}
impl PartialOrd for Number {
fn partial_cmp(&self, other: &Number) -> Option<Ordering> {
Some(self.cmp(other))
}
}
impl Ord for Number {
fn cmp(&self, other: &Self) -> Ordering {
use Number::{Float, Signed, Unsigned};
match (*self, *other) {
(Unsigned(a), Unsigned(b)) => a.cmp(&b),
(Unsigned(a), Signed(b)) => {
if b < 0 {
Ordering::Greater
} else {
a.cmp(&(b as u64))
}
}
(Unsigned(a), Float(b)) => (OrderedFloat(a as f64)).cmp(&b),
(Signed(a), Unsigned(b)) => {
if a < 0 {
Ordering::Less
} else {
(a as u64).cmp(&b)
}
}
(Signed(a), Signed(b)) => a.cmp(&b),
(Signed(a), Float(b)) => OrderedFloat(a as f64).cmp(&b),
(Float(a), Unsigned(b)) => a.cmp(&OrderedFloat(b as f64)),
(Float(a), Signed(b)) => a.cmp(&OrderedFloat(b as f64)),
(Float(a), Float(b)) => a.cmp(&b),
}
}
}
#[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
)
}
}
}