//! Fast lexical string-to-integer conversion routines.

use util::*;
use super::generic::*;

// ATOI TRAIT
// ----------

pub(crate) trait Atoi: Integer {
    // Parse integer from string.
    fn atoi(bytes: &[u8], radix: u32) -> ParseResult<(Self, *const u8)>;

    // Parse integer from string with format.
    #[cfg(feature = "format")]
    fn atoi_format(bytes: &[u8], radix: u32, format: NumberFormat) -> ParseResult<(Self, *const u8)>;
}

// Implement atoi for type.
macro_rules! atoi_impl {
    ($($t:ty)*) => ($(
        impl Atoi for $t {
            perftools_inline_always!{
            fn atoi(bytes: &[u8], radix: u32)
                -> ParseResult<($t, *const u8)>
            {
                standalone_no_separator(bytes, radix)
            }}

            perftools_inline_always!{
            #[cfg(feature = "format")]
            fn atoi_format(bytes: &[u8], radix: u32, format: NumberFormat)
                -> ParseResult<($t, *const u8)>
            {
                standalone_separator(bytes, radix, format)
            }}
        }
    )*);
}

atoi_impl! { u8 u16 u32 u64 usize i8 i16 i32 i64 isize }

#[cfg(has_i128)]
impl Atoi for u128 {
    perftools_inline_always!{
    fn atoi(bytes: &[u8], radix: u32)
        -> ParseResult<(u128, *const u8)>
    {
        standalone_128_no_separator::<u128, u64>(bytes, radix)
    }}

    perftools_inline_always!{
    #[cfg(feature = "format")]
    fn atoi_format(bytes: &[u8], radix: u32, format: NumberFormat)
        -> ParseResult<(u128, *const u8)>
    {
        standalone_128_separator::<u128, u64>(bytes, radix, format)
    }}
}

#[cfg(has_i128)]
impl Atoi for i128 {
    perftools_inline_always!{
    fn atoi(bytes: &[u8], radix: u32)
        -> ParseResult<(i128, *const u8)>
    {
        standalone_128_no_separator::<i128, i64>(bytes, radix)
    }}

    perftools_inline_always!{
    #[cfg(feature = "format")]
    fn atoi_format(bytes: &[u8], radix: u32, format: NumberFormat)
        -> ParseResult<(i128, *const u8)>
    {
        standalone_128_separator::<i128, i64>(bytes, radix, format)
    }}
}

// ATOI
// ----

perftools_inline!{
pub(crate) fn atoi<'a, T>(bytes: &'a [u8], radix: u32)
    -> Result<(T, usize)>
    where T: Atoi
{
    let index = | ptr | distance(bytes.as_ptr(), ptr);
    match T::atoi(bytes, radix) {
        Ok((value, ptr)) => Ok((value, index(ptr))),
        Err((code, ptr)) => Err((code, index(ptr)).into()),
    }
}}

perftools_inline!{
#[cfg(feature = "format")]
pub(crate) fn atoi_format<'a, T>(bytes: &'a [u8], radix: u32, format: NumberFormat)
    -> Result<(T, usize)>
    where T: Atoi
{
    let index = | ptr | distance(bytes.as_ptr(), ptr);
    match T::atoi_format(bytes, radix, format) {
        Ok((value, ptr)) => Ok((value, index(ptr))),
        Err((code, ptr)) => Err((code, index(ptr)).into()),
    }
}}

// FROM LEXICAL
// ------------

from_lexical!(atoi, u8);
from_lexical!(atoi, u16);
from_lexical!(atoi, u32);
from_lexical!(atoi, u64);
from_lexical!(atoi, usize);
#[cfg(has_i128)] from_lexical!(atoi, u128);

from_lexical!(atoi, i8);
from_lexical!(atoi, i16);
from_lexical!(atoi, i32);
from_lexical!(atoi, i64);
from_lexical!(atoi, isize);
#[cfg(has_i128)] from_lexical!(atoi, i128);

cfg_if!{
if #[cfg(feature = "format")] {
    from_lexical_format!(atoi_format, u8);
    from_lexical_format!(atoi_format, u16);
    from_lexical_format!(atoi_format, u32);
    from_lexical_format!(atoi_format, u64);
    from_lexical_format!(atoi_format, usize);
    #[cfg(has_i128)] from_lexical_format!(atoi_format, u128);

    from_lexical_format!(atoi_format, i8);
    from_lexical_format!(atoi_format, i16);
    from_lexical_format!(atoi_format, i32);
    from_lexical_format!(atoi_format, i64);
    from_lexical_format!(atoi_format, isize);
    #[cfg(has_i128)] from_lexical_format!(atoi_format, i128);
}}

// TESTS
// -----

#[cfg(test)]
mod tests {
    use util::*;

    #[cfg(feature = "radix")]
    const DATA: [(u8, &'static str); 35] = [
        (2, "100101"),
        (3, "1101"),
        (4, "211"),
        (5, "122"),
        (6, "101"),
        (7, "52"),
        (8, "45"),
        (9, "41"),
        (10, "37"),
        (11, "34"),
        (12, "31"),
        (13, "2B"),
        (14, "29"),
        (15, "27"),
        (16, "25"),
        (17, "23"),
        (18, "21"),
        (19, "1I"),
        (20, "1H"),
        (21, "1G"),
        (22, "1F"),
        (23, "1E"),
        (24, "1D"),
        (25, "1C"),
        (26, "1B"),
        (27, "1A"),
        (28, "19"),
        (29, "18"),
        (30, "17"),
        (31, "16"),
        (32, "15"),
        (33, "14"),
        (34, "13"),
        (35, "12"),
        (36, "11"),
    ];

    #[test]
    fn u8_decimal_test() {
        assert_eq!(Ok(0), u8::from_lexical(b"0"));
        assert_eq!(Ok(127), u8::from_lexical(b"127"));
        assert_eq!(Ok(128), u8::from_lexical(b"128"));
        assert_eq!(Ok(255), u8::from_lexical(b"255"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 0).into()), u8::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), u8::from_lexical(b"1a"));
    }

    #[cfg(feature = "radix")]
    #[test]
    fn u8_radix_test() {
        for (b, s) in DATA.iter() {
            assert_eq!(u8::from_lexical_radix(s.as_bytes(), *b), Ok(37));
        }
    }

    #[test]
    fn i8_decimal_test() {
        assert_eq!(Ok(0), i8::from_lexical(b"0"));
        assert_eq!(Ok(127), i8::from_lexical(b"127"));
        assert_eq!(Err((ErrorCode::Overflow, 2).into()), i8::from_lexical(b"128"));
        assert_eq!(Err((ErrorCode::Overflow, 2).into()), i8::from_lexical(b"255"));
        assert_eq!(Ok(-1), i8::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), i8::from_lexical(b"1a"));
    }

    #[cfg(feature = "radix")]
    #[test]
    fn i8_radix_test() {
        for (b, s) in DATA.iter() {
            assert_eq!(i8::from_lexical_radix(s.as_bytes(), *b), Ok(37));
        }
    }

    #[test]
    fn u16_decimal_test() {
        assert_eq!(Ok(0), u16::from_lexical(b"0"));
        assert_eq!(Ok(32767), u16::from_lexical(b"32767"));
        assert_eq!(Ok(32768), u16::from_lexical(b"32768"));
        assert_eq!(Ok(65535), u16::from_lexical(b"65535"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 0).into()), u16::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), u16::from_lexical(b"1a"));
    }

    #[test]
    fn i16_decimal_test() {
        assert_eq!(Ok(0), i16::from_lexical(b"0"));
        assert_eq!(Ok(32767), i16::from_lexical(b"32767"));
        assert_eq!(Err((ErrorCode::Overflow, 4).into()), i16::from_lexical(b"32768"));
        assert_eq!(Err((ErrorCode::Overflow, 4).into()), i16::from_lexical(b"65535"));
        assert_eq!(Ok(-1), i16::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), i16::from_lexical(b"1a"));
    }

    #[cfg(feature = "radix")]
    #[test]
    fn i16_radix_test() {
        for (b, s) in DATA.iter() {
            assert_eq!(i16::from_lexical_radix(s.as_bytes(), *b), Ok(37));
        }
        assert_eq!(i16::from_lexical_radix(b"YA", 36), Ok(1234));
    }

    #[test]
    fn u32_decimal_test() {
        assert_eq!(Ok(0), u32::from_lexical(b"0"));
        assert_eq!(Ok(2147483647), u32::from_lexical(b"2147483647"));
        assert_eq!(Ok(2147483648), u32::from_lexical(b"2147483648"));
        assert_eq!(Ok(4294967295), u32::from_lexical(b"4294967295"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 0).into()), u32::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), u32::from_lexical(b"1a"));
    }

    #[test]
    fn i32_decimal_test() {
        assert_eq!(Ok(0), i32::from_lexical(b"0"));
        assert_eq!(Ok(2147483647), i32::from_lexical(b"2147483647"));
        assert_eq!(Err((ErrorCode::Overflow, 9).into()), i32::from_lexical(b"2147483648"));
        assert_eq!(Err((ErrorCode::Overflow, 9).into()), i32::from_lexical(b"4294967295"));
        assert_eq!(Ok(-1), i32::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), i32::from_lexical(b"1a"));
    }

    #[test]
    fn u64_decimal_test() {
        assert_eq!(Ok(0), u64::from_lexical(b"0"));
        assert_eq!(Ok(9223372036854775807), u64::from_lexical(b"9223372036854775807"));
        assert_eq!(Ok(9223372036854775808), u64::from_lexical(b"9223372036854775808"));
        assert_eq!(Ok(18446744073709551615), u64::from_lexical(b"18446744073709551615"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 0).into()), u64::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), u64::from_lexical(b"1a"));
    }

    #[test]
    fn i64_decimal_test() {
        assert_eq!(Ok(0), i64::from_lexical(b"0"));
        assert_eq!(Ok(9223372036854775807), i64::from_lexical(b"9223372036854775807"));
        assert_eq!(Err((ErrorCode::Overflow, 18).into()), i64::from_lexical(b"9223372036854775808"));
        assert_eq!(Err((ErrorCode::Overflow, 19).into()), i64::from_lexical(b"18446744073709551615"));
        assert_eq!(Ok(-1), i64::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), i64::from_lexical(b"1a"));

        // Add tests discovered via fuzzing.
        assert_eq!(Err((ErrorCode::Overflow, 19).into()), i64::from_lexical(b"406260572150672006000066000000060060007667760000000000000000000+00000006766767766666767665670000000000000000000000666"));
    }

    #[test]
    fn u128_decimal_test() {
        assert_eq!(Ok(0), u128::from_lexical(b"0"));
        assert_eq!(Ok(170141183460469231731687303715884105727), u128::from_lexical(b"170141183460469231731687303715884105727"));
        assert_eq!(Ok(170141183460469231731687303715884105728), u128::from_lexical(b"170141183460469231731687303715884105728"));
        assert_eq!(Ok(340282366920938463463374607431768211455), u128::from_lexical(b"340282366920938463463374607431768211455"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 0).into()), u128::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), u128::from_lexical(b"1a"));
    }

    #[test]
    fn i128_decimal_test() {
        assert_eq!(Ok(0), i128::from_lexical(b"0"));
        assert_eq!(Ok(170141183460469231731687303715884105727), i128::from_lexical(b"170141183460469231731687303715884105727"));
        assert_eq!(Err((ErrorCode::Overflow, 39).into()), i128::from_lexical(b"170141183460469231731687303715884105728"));
        assert_eq!(Err((ErrorCode::Overflow, 39).into()), i128::from_lexical(b"340282366920938463463374607431768211455"));
        assert_eq!(Ok(-1), i128::from_lexical(b"-1"));
        assert_eq!(Err((ErrorCode::InvalidDigit, 1).into()), i128::from_lexical(b"1a"));
    }

    #[test]
    #[cfg(feature = "format")]
    fn i32_no_leading_zeros_test() {
        let format = NumberFormat::NO_INTEGER_LEADING_ZEROS;
        assert!(i32::from_lexical_format(b"1", format).is_ok());
        assert!(i32::from_lexical_format(b"0", format).is_ok());
        assert!(i32::from_lexical_format(b"01", format).is_err());
        assert!(i32::from_lexical_format(b"10", format).is_ok());
        assert!(i32::from_lexical_format(b"010", format).is_err());
    }

    #[test]
    #[cfg(feature = "format")]
    fn i32_integer_internal_digit_separator_test() {
        let format = NumberFormat::from_separator(b'_') | NumberFormat::INTEGER_INTERNAL_DIGIT_SEPARATOR;
        assert!(i32::from_lexical_format(b"3_1", format).is_ok());
        assert!(i32::from_lexical_format(b"_31", format).is_err());
        assert!(i32::from_lexical_format(b"31_", format).is_err());
    }

    #[test]
    #[cfg(feature = "format")]
    fn i32_integer_leading_digit_separator_test() {
        let format = NumberFormat::from_separator(b'_') | NumberFormat::INTEGER_LEADING_DIGIT_SEPARATOR;
        assert!(i32::from_lexical_format(b"3_1", format).is_err());
        assert!(i32::from_lexical_format(b"_31", format).is_ok());
        assert!(i32::from_lexical_format(b"31_", format).is_err());
    }

    #[test]
    #[cfg(feature = "format")]
    fn i32_integer_trailing_digit_separator_test() {
        let format = NumberFormat::from_separator(b'_') | NumberFormat::INTEGER_TRAILING_DIGIT_SEPARATOR;
        assert!(i32::from_lexical_format(b"3_1", format).is_err());
        assert!(i32::from_lexical_format(b"_31", format).is_err());
        assert!(i32::from_lexical_format(b"31_", format).is_ok());
    }

    #[test]
    #[cfg(feature = "format")]
    fn i32_integer_consecutive_digit_separator_test() {
        let format = NumberFormat::from_separator(b'_')
            | NumberFormat::INTEGER_INTERNAL_DIGIT_SEPARATOR
            | NumberFormat::INTEGER_CONSECUTIVE_DIGIT_SEPARATOR;
        assert!(i32::from_lexical_format(b"3_1", format).is_ok());
        assert!(i32::from_lexical_format(b"3__1", format).is_ok());
        assert!(i32::from_lexical_format(b"_31", format).is_err());
        assert!(i32::from_lexical_format(b"31_", format).is_err());
    }

    #[test]
    #[cfg(feature = "format")]
    fn i32_json_no_leading_zero() {
        let format = NumberFormat::JSON;
        assert!(i32::from_lexical_format(b"12", format).is_ok());
        assert!(i32::from_lexical_format(b"-12", format).is_ok());
        assert!(i32::from_lexical_format(b"012", format).is_err());
        assert!(i32::from_lexical_format(b"-012", format).is_err());
    }

    #[cfg(all(feature = "std", feature = "property_tests"))]
    proptest! {
        #[test]
        fn u8_invalid_proptest(i in r"[+]?[0-9]{2}\D") {
            let result = u8::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let index = result.err().unwrap().index;
            prop_assert!(index == 2 || index == 3);
        }

        #[test]
        fn u8_overflow_proptest(i in r"[+]?[1-9][0-9]{3}") {
            let result = u8::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn u8_negative_proptest(i in r"[-][1-9][0-9]{2}") {
            let result = u8::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::InvalidDigit);
        }

        #[test]
        fn u8_double_sign_proptest(i in r"[+]{2}[0-9]{2}") {
            let result = u8::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn u8_sign_only_proptest(i in r"[+]") {
            let result = u8::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Empty);
        }

        #[test]
        fn u8_trailing_digits_proptest(i in r"[+]?[0-9]{2}\D[0-9]{2}") {
            let result = u8::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 2 || error.index == 3);
        }

        #[test]
        fn i8_invalid_proptest(i in r"[+-]?[0-9]{2}\D") {
            let result = i8::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 2 || error.index == 3);
        }

        #[test]
        fn i8_overflow_proptest(i in r"[+]?[1-9][0-9]{3}\D") {
            let result = i8::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn i8_underflow_proptest(i in r"[-][1-9][0-9]{3}\D") {
            let result = i8::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Underflow);
        }

        #[test]
        fn i8_double_sign_proptest(i in r"[+-]{2}[0-9]{2}") {
            let result = i8::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn i8_sign_only_proptest(i in r"[+-]") {
            let result = i8::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::Empty);
        }

        #[test]
        fn i8_trailing_digits_proptest(i in r"[+-]?[0-9]{2}\D[0-9]{2}") {
            let result = i8::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 2 || error.index == 3);
        }

        #[test]
        fn u16_invalid_proptest(i in r"[+]?[0-9]{4}\D") {
            let result = u16::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 4 || error.index == 5);
        }

        #[test]
        fn u16_overflow_proptest(i in r"[+]?[1-9][0-9]{5}\D") {
            let result = u16::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn u16_negative_proptest(i in r"[-][1-9][0-9]{4}") {
            let result = u16::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::InvalidDigit);
        }

        #[test]
        fn u16_double_sign_proptest(i in r"[+]{2}[0-9]{4}") {
            let result = u16::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn u16_sign_only_proptest(i in r"[+]") {
            let result = u16::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Empty);
        }

        #[test]
        fn u16_trailing_digits_proptest(i in r"[+]?[0-9]{4}\D[0-9]{2}") {
            let result = u16::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 4 || error.index == 5);
        }

        #[test]
        fn i16_invalid_proptest(i in r"[+-]?[0-9]{4}\D") {
            let result = i16::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 4 || error.index == 5);
        }

        #[test]
        fn i16_overflow_proptest(i in r"[+]?[1-9][0-9]{5}\D") {
            let result = i16::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn i16_underflow_proptest(i in r"[-][1-9][0-9]{5}\DD") {
            let result = i16::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Underflow);
        }

        #[test]
        fn i16_double_sign_proptest(i in r"[+-]{2}[0-9]{4}") {
            let result = i16::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn i16_sign_only_proptest(i in r"[+-]") {
            let result = i16::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Empty);
        }

        #[test]
        fn i16_trailing_digits_proptest(i in r"[+-]?[0-9]{4}\D[0-9]{2}") {
            let result = i16::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 4 || error.index == 5);
        }

        #[test]
        fn u32_invalid_proptest(i in r"[+]?[0-9]{9}\D") {
            let result = u32::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 9 || error.index == 10);
        }

        #[test]
        fn u32_overflow_proptest(i in r"[+]?[1-9][0-9]{10}\D") {
            let result = u32::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn u32_negative_proptest(i in r"[-][1-9][0-9]{9}") {
            let result = u32::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::InvalidDigit);
        }

        #[test]
        fn u32_double_sign_proptest(i in r"[+]{2}[0-9]{9}") {
            let result = u32::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn u32_sign_only_proptest(i in r"[+]") {
            let result = u32::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Empty);
        }

        #[test]
        fn u32_trailing_digits_proptest(i in r"[+]?[0-9]{9}\D[0-9]{2}") {
            let result = u32::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 9 || error.index == 10);
        }

        #[test]
        fn i32_invalid_proptest(i in r"[+-]?[0-9]{9}\D") {
            let result = i32::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 9 || error.index == 10);
        }

        #[test]
        fn i32_overflow_proptest(i in r"[+]?[1-9][0-9]{10}\D") {
            let result = i32::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn i32_underflow_proptest(i in r"-[1-9][0-9]{10}\D") {
            let result = i32::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Underflow);
        }

        #[test]
        fn i32_double_sign_proptest(i in r"[+-]{2}[0-9]{9}") {
            let result = i32::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn i32_sign_only_proptest(i in r"[+-]") {
            let result = i32::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Empty);
        }

        #[test]
        fn i32_trailing_digits_proptest(i in r"[+-]?[0-9]{9}\D[0-9]{2}") {
            let result = i32::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 9 || error.index == 10);
        }

        #[test]
        fn u64_invalid_proptest(i in r"[+]?[0-9]{19}\D") {
            let result = u64::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 19 || error.index == 20);
        }

        #[test]
        fn u64_overflow_proptest(i in r"[+]?[1-9][0-9]{21}\D") {
            let result = u64::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn u64_negative_proptest(i in r"[-][1-9][0-9]{21}") {
            let result = u64::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::InvalidDigit);
        }

        #[test]
        fn u64_double_sign_proptest(i in r"[+]{2}[0-9]{19}") {
            let result = u64::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn u64_sign_only_proptest(i in r"[+]") {
            let result = u64::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Empty);
        }

        #[test]
        fn u64_trailing_digits_proptest(i in r"[+]?[0-9]{19}\D[0-9]{2}") {
            let result = u64::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 19 || error.index == 20);
        }

        #[test]
        fn i64_invalid_proptest(i in r"[+-]?[0-9]{18}\D") {
            let result = i64::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 18 || error.index == 19);
        }

        #[test]
        fn i64_overflow_proptest(i in r"[+]?[1-9][0-9]{19}\D") {
            let result = i64::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Overflow);
        }

        #[test]
        fn i64_underflow_proptest(i in r"-[1-9][0-9]{19}\D") {
            let result = i64::from_lexical(i.as_bytes());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Underflow);
        }

        #[test]
        fn i64_double_sign_proptest(i in r"[+-]{2}[0-9]{18}") {
            let result = i64::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 1);
        }

        #[test]
        fn i64_sign_only_proptest(i in r"[+-]") {
            let result = i32::from_lexical(i.as_bytes());
            prop_assert!(result.is_err());
            let code = result.err().unwrap().code;
            prop_assert_eq!(code, ErrorCode::Empty);
        }

        #[test]
        fn i64_trailing_digits_proptest(i in r"[+-]?[0-9]{18}\D[0-9]{2}") {
            let result = i64::from_lexical(i.as_bytes());
            let error = result.err().unwrap();
            prop_assert_eq!(error.code, ErrorCode::InvalidDigit);
            prop_assert!(error.index == 18 || error.index == 19);
        }
    }
}