use bigdecimal::BigDecimal;
use combine::parser::char::{char as char_, digit};
use combine::{many1, optional, ParseError, Parser};
use std::str::FromStr;
use crate::expr::Expr;
use crate::parser::errors::RibParseError;
use crate::rib_source_span::GetSourcePosition;
pub fn integer<Input>() -> impl Parser<Input, Output = Expr>
where
Input: combine::Stream<Token = char>,
Input::Error: ParseError<Input::Token, Input::Range, Input::Position>,
RibParseError: Into<
<Input::Error as ParseError<Input::Token, Input::Range, Input::Position>>::StreamError,
>,
Input::Position: GetSourcePosition,
{
let digits = many1(digit());
(optional(char_('-')), digits).map(|(sign, num_str): (Option<char>, String)| {
let num = BigDecimal::from_str(&num_str).unwrap();
let big_decimal = if sign.is_some() { -num } else { num };
Expr::number(big_decimal)
})
}
#[cfg(test)]
mod tests {
use super::*;
use crate::TypeName;
use test_r::test;
#[test]
fn test_number() {
let input = "123";
let result = Expr::from_text(input);
assert_eq!(result, Ok(Expr::number(BigDecimal::from(123))));
}
#[test]
fn test_negative_number() {
let input = "-123";
let result = Expr::from_text(input);
assert_eq!(result, Ok(Expr::number(BigDecimal::from(-123))));
}
#[test]
fn test_number_with_binding_positive() {
let input = "123u32";
let result = Expr::from_text(input);
let expected = Expr::number(BigDecimal::from(123)).with_type_annotation(TypeName::U32);
assert_eq!(result, Ok(expected));
}
#[test]
fn test_number_with_binding_negative() {
let input = "-123s64";
let result = Expr::from_text(input);
let expected = Expr::number(BigDecimal::from(-123)).with_type_annotation(TypeName::S64);
assert_eq!(result, Ok(expected));
}
}