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use std::fmt;
use std::mem::{align_of, size_of};
mod str32;
mod string32;
pub use crate::string32::String32;
pub use str32::Str32;
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct TryFromStringError<T>(T);
impl<T> TryFromStringError<T> {
pub fn into_inner(self) -> T {
self.0
}
}
impl<T> fmt::Display for TryFromStringError<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "string too large for u32-indexed buffer")
}
}
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub struct TryFromStrError(());
impl fmt::Display for TryFromStrError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "string too large for u32-indexed buffer")
}
}
macro_rules! comptime_assert_eq {
($lhs:expr, $rhs:expr $(,)?) => {
const _: [(); ($lhs == $rhs) as usize - 1] = [];
};
}
comptime_assert_eq!(size_of::<String32>(), 8 + size_of::<usize>());
comptime_assert_eq!(align_of::<String32>(), align_of::<usize>());
comptime_assert_eq!(size_of::<&str>(), size_of::<&Str32>());
comptime_assert_eq!(align_of::<&str>(), align_of::<&Str32>());
#[cfg(test)]
mod tests {
use super::*;
use std::convert::TryFrom;
const TEXT: &str = include_str!("lib.rs");
#[test]
fn test_simple() {
let s1 = String::from(TEXT);
let mut s2 = String32::new();
s2.push_str(TEXT);
assert_eq!(&s1, &s2);
assert_eq!(s1, s2);
}
#[test]
fn test_complex() {
let mut s = String32::try_from(TEXT).unwrap();
s.shrink_to_fit();
s.push('\n');
s.reserve_exact(2 * s.len());
s.reserve(1);
s.push_str(TEXT);
s.pop();
s.remove(s.len() - 1);
s.remove(0);
s.insert(s.len() - 1, '\n');
s.insert(0, '\n');
s.insert_str(0, TEXT);
s.truncate(s.len() / 2);
let mut other = s.split_off(s.len() / 2);
other.push_str(&s);
assert!(!other.is_empty());
}
#[test]
fn test_hash() {
use std::collections::hash_map::DefaultHasher;
use std::hash::{Hash, Hasher};
let mut hash1 = DefaultHasher::new();
let mut hash2 = DefaultHasher::new();
let s1 = String::from(TEXT);
let s2 = String32::try_from(TEXT).unwrap();
<String as Hash>::hash(&s1, &mut hash1);
<String32 as Hash>::hash(&s2, &mut hash2);
<str as Hash>::hash(&s1, &mut hash1);
<Str32 as Hash>::hash(&s2, &mut hash2);
assert_eq!(hash1.finish(), hash2.finish());
}
}