//! `ArrayString` definition and Api implementation
use crate::utils::{encode_char_utf8_unchecked, is_char_boundary, is_inside_boundary, never};
use crate::utils::{shift_left_unchecked, shift_right_unchecked, truncate_str, IntoLossy};
use crate::{error::Error, generic::ArraySlice, prelude::*};
use core::char::{decode_utf16, REPLACEMENT_CHARACTER};
use core::str::{from_utf8, from_utf8_unchecked};
use core::{cmp::min, ops::*, ptr::copy_nonoverlapping};
#[cfg(feature = "logs")]
use log::{debug, trace};
use crate::generic::Capacity;
/// String based on a generic array (size defined at compile time through `typenum`)
///
/// Can't outgrow capacity (defined at compile time), always occupies [`capacity`] `+ 1` bytes of memory
///
/// *Doesn't allocate memory on the heap and never panics (all panic branches are stripped at compile time)*
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
#[derive(Clone)]
pub struct ArrayString<SIZE: Capacity> {
/// Array type corresponding to specified `SIZE`
pub(crate) array: SIZE::Array,
/// Current string size
pub(crate) size: u8,
}
impl<SIZE: Capacity> ArrayString<SIZE> {
/// Creates new empty string.
///
/// ```rust
/// # use arraystring::prelude::*;
/// # let _ = env_logger::try_init();
/// let string = SmallString::new();
/// assert!(string.is_empty());
/// ```
#[inline]
pub fn new() -> Self {
trace!("New empty ArrayString");
Self::default()
}
/// Creates new `ArrayString` from string slice if length is lower or equal to [`capacity`], otherwise returns an error.
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let string = SmallString::try_from_str("My String")?;
/// assert_eq!(string.as_str(), "My String");
///
/// assert_eq!(SmallString::try_from_str("")?.as_str(), "");
///
/// let out_of_bounds = "0".repeat(SmallString::capacity() as usize + 1);
/// assert!(SmallString::try_from_str(out_of_bounds).is_err());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_from_str<S>(s: S) -> Result<Self, OutOfBounds>
where
S: AsRef<str>,
{
trace!("Try from str: {:?}", s.as_ref());
is_inside_boundary(s.as_ref().len(), Self::capacity())?;
unsafe { Ok(Self::from_str_unchecked(s.as_ref())) }
}
/// Creates new `ArrayString` from string slice truncating size if bigger than [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// # let _ = env_logger::try_init();
/// let string = SmallString::from_str_truncate("My String");
/// # assert_eq!(string.as_str(), "My String");
/// println!("{}", string);
///
/// let truncate = "0".repeat(SmallString::capacity() as usize + 1);
/// let truncated = "0".repeat(SmallString::capacity().into());
/// let string = SmallString::from_str_truncate(&truncate);
/// assert_eq!(string.as_str(), truncated);
/// ```
#[inline]
pub fn from_str_truncate<S>(string: S) -> Self
where
S: AsRef<str>,
{
trace!("FromStr truncate");
unsafe { Self::from_str_unchecked(truncate_str(string.as_ref(), Self::capacity())) }
}
/// Creates new `ArrayString` from string slice assuming length is appropriate.
///
/// # Safety
///
/// It's UB if `string.len()` > [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// let filled = "0".repeat(SmallString::capacity().into());
/// let string = unsafe {
/// SmallString::from_str_unchecked(&filled)
/// };
/// assert_eq!(string.as_str(), filled.as_str());
///
/// // Undefined behavior, don't do it
/// // let out_of_bounds = "0".repeat(SmallString::capacity().into() + 1);
/// // let ub = unsafe { SmallString::from_str_unchecked(out_of_bounds) };
/// ```
#[inline]
pub unsafe fn from_str_unchecked<S>(string: S) -> Self
where
S: AsRef<str>,
{
trace!("FromStr unchecked");
let mut out = Self::default();
out.push_str_unchecked(string);
out
}
/// Creates new `ArrayString` from string slice iterator if total length is lower or equal to [`capacity`], otherwise returns an error.
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// # fn main() -> Result<(), OutOfBounds> {
/// let string = MaxString::try_from_iterator(&["My String", " My Other String"][..])?;
/// assert_eq!(string.as_str(), "My String My Other String");
///
/// let out_of_bounds = (0..100).map(|_| "000");
/// assert!(SmallString::try_from_iterator(out_of_bounds).is_err());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_from_iterator<U, I>(iter: I) -> Result<Self, OutOfBounds>
where
U: AsRef<str>,
I: IntoIterator<Item = U>,
{
trace!("FromIterator");
let mut out = Self::default();
for s in iter {
out.try_push_str(s)?;
}
Ok(out)
}
/// Creates new `ArrayString` from string slice iterator truncating size if bigger than [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// # fn main() -> Result<(), OutOfBounds> {
/// # let _ = env_logger::try_init();
/// let string = MaxString::from_iterator(&["My String", " Other String"][..]);
/// assert_eq!(string.as_str(), "My String Other String");
///
/// let out_of_bounds = (0..400).map(|_| "000");
/// let truncated = "0".repeat(SmallString::capacity().into());
///
/// let truncate = SmallString::from_iterator(out_of_bounds);
/// assert_eq!(truncate.as_str(), truncated.as_str());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn from_iterator<U, I>(iter: I) -> Self
where
U: AsRef<str>,
I: IntoIterator<Item = U>,
{
trace!("FromIterator truncate");
let mut out = Self::default();
for s in iter {
if out.try_push_str(s.as_ref()).is_err() {
out.push_str(s);
break;
}
}
out
}
/// Creates new `ArrayString` from string slice iterator assuming length is appropriate.
///
/// # Safety
///
/// It's UB if `iter.map(|c| c.len()).sum()` > [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// let string = unsafe {
/// MaxString::from_iterator_unchecked(&["My String", " My Other String"][..])
/// };
/// assert_eq!(string.as_str(), "My String My Other String");
///
/// // Undefined behavior, don't do it
/// // let out_of_bounds = (0..400).map(|_| "000");
/// // let undefined_behavior = unsafe {
/// // SmallString::from_iterator_unchecked(out_of_bounds)
/// // };
/// ```
#[inline]
pub unsafe fn from_iterator_unchecked<U, I>(iter: I) -> Self
where
U: AsRef<str>,
I: IntoIterator<Item = U>,
{
trace!("FromIterator unchecked");
let mut out = Self::default();
for s in iter {
out.push_str_unchecked(s);
}
out
}
/// Creates new `ArrayString` from char iterator if total length is lower or equal to [`capacity`], otherwise returns an error.
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let string = SmallString::try_from_chars("My String".chars())?;
/// assert_eq!(string.as_str(), "My String");
///
/// let out_of_bounds = "0".repeat(SmallString::capacity() as usize + 1);
/// assert!(SmallString::try_from_chars(out_of_bounds.chars()).is_err());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_from_chars<I>(iter: I) -> Result<Self, OutOfBounds>
where
I: IntoIterator<Item = char>,
{
trace!("TryFrom chars");
let mut out = Self::default();
for c in iter {
out.try_push(c)?;
}
Ok(out)
}
/// Creates new `ArrayString` from char iterator truncating size if bigger than [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// # let _ = env_logger::try_init();
/// let string = SmallString::from_chars("My String".chars());
/// assert_eq!(string.as_str(), "My String");
///
/// let out_of_bounds = "0".repeat(SmallString::capacity() as usize + 1);
/// let truncated = "0".repeat(SmallString::capacity().into());
///
/// let truncate = SmallString::from_chars(out_of_bounds.chars());
/// assert_eq!(truncate.as_str(), truncated.as_str());
/// ```
#[inline]
pub fn from_chars<I>(iter: I) -> Self
where
I: IntoIterator<Item = char>,
{
trace!("From chars truncate");
let mut out = Self::default();
for c in iter {
if out.try_push(c).is_err() {
break;
}
}
out
}
/// Creates new `ArrayString` from char iterator assuming length is appropriate.
///
/// # Safety
///
/// It's UB if `iter.map(|c| c.len_utf8()).sum()` > [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// let string = unsafe { SmallString::from_chars_unchecked("My String".chars()) };
/// assert_eq!(string.as_str(), "My String");
///
/// // Undefined behavior, don't do it
/// // let out_of_bounds = "000".repeat(400);
/// // let undefined_behavior = unsafe { SmallString::from_chars_unchecked(out_of_bounds.chars()) };
/// ```
#[inline]
pub unsafe fn from_chars_unchecked<I>(iter: I) -> Self
where
I: IntoIterator<Item = char>,
{
trace!("From chars unchecked");
let mut out = Self::default();
for c in iter {
out.push_unchecked(c)
}
out
}
/// Creates new `ArrayString` from byte slice, returning [`Utf8`] on invalid utf-8 data or [`OutOfBounds`] if bigger than [`capacity`]
///
/// [`Utf8`]: ./error/enum.Error.html#variant.Utf8
/// [`OutOfBounds`]: ./error/enum.Error.html#variant.OutOfBounds
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let string = SmallString::try_from_utf8("My String")?;
/// assert_eq!(string.as_str(), "My String");
///
/// let invalid_utf8 = [0, 159, 146, 150];
/// assert_eq!(SmallString::try_from_utf8(invalid_utf8), Err(Error::Utf8));
///
/// let out_of_bounds = "0000".repeat(400);
/// assert_eq!(SmallString::try_from_utf8(out_of_bounds.as_bytes()), Err(Error::OutOfBounds));
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_from_utf8<B>(slice: B) -> Result<Self, Error>
where
B: AsRef<[u8]>,
{
debug!("From utf8: {:?}", slice.as_ref());
Ok(Self::try_from_str(from_utf8(slice.as_ref())?)?)
}
/// Creates new `ArrayString` from byte slice, returning [`Utf8`] on invalid utf-8 data, truncating if bigger than [`capacity`].
///
/// [`Utf8`]: ./error/struct.Utf8.html
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let string = SmallString::from_utf8("My String")?;
/// assert_eq!(string.as_str(), "My String");
///
/// let invalid_utf8 = [0, 159, 146, 150];
/// assert_eq!(SmallString::from_utf8(invalid_utf8), Err(Utf8));
///
/// let out_of_bounds = "0".repeat(300);
/// assert_eq!(SmallString::from_utf8(out_of_bounds.as_bytes())?.as_str(),
/// "0".repeat(SmallString::capacity().into()).as_str());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn from_utf8<B>(slice: B) -> Result<Self, Utf8>
where
B: AsRef<[u8]>,
{
debug!("From utf8: {:?}", slice.as_ref());
Ok(Self::from_str_truncate(from_utf8(slice.as_ref())?))
}
/// Creates new `ArrayString` from byte slice assuming it's utf-8 and of a appropriate size.
///
/// # Safety
///
/// It's UB if `slice` is not a valid utf-8 string or `slice.len()` > [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::prelude::*;
/// let string = unsafe { SmallString::from_utf8_unchecked("My String") };
/// assert_eq!(string.as_str(), "My String");
///
/// // Undefined behavior, don't do it
/// // let out_of_bounds = "0".repeat(300);
/// // let ub = unsafe { SmallString::from_utf8_unchecked(out_of_bounds)) };
/// ```
#[inline]
pub unsafe fn from_utf8_unchecked<B>(slice: B) -> Self
where
B: AsRef<[u8]>,
{
trace!("From utf8 unchecked");
debug_assert!(from_utf8(slice.as_ref()).is_ok());
Self::from_str_unchecked(from_utf8_unchecked(slice.as_ref()))
}
/// Creates new `ArrayString` from `u16` slice, returning [`Utf16`] on invalid utf-16 data or [`OutOfBounds`] if bigger than [`capacity`]
///
/// [`Utf16`]: ./error/enum.Error.html#variant.Utf16
/// [`OutOfBounds`]: ./error/enum.Error.html#variant.OutOfBounds
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let music = [0xD834, 0xDD1E, 0x006d, 0x0075, 0x0073, 0x0069, 0x0063];
/// let string = SmallString::try_from_utf16(music)?;
/// assert_eq!(string.as_str(), "𝄞music");
///
/// let invalid_utf16 = [0xD834, 0xDD1E, 0x006d, 0x0075, 0xD800, 0x0069, 0x0063];
/// assert_eq!(SmallString::try_from_utf16(invalid_utf16), Err(Error::Utf16));
///
/// let out_of_bounds: Vec<_> = (0..300).map(|_| 0).collect();
/// assert_eq!(SmallString::try_from_utf16(out_of_bounds), Err(Error::OutOfBounds));
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_from_utf16<B>(slice: B) -> Result<Self, Error>
where
B: AsRef<[u16]>,
{
debug!("From utf16: {:?}", slice.as_ref());
let mut out = Self::default();
for c in decode_utf16(slice.as_ref().iter().cloned()) {
out.try_push(c?)?;
}
Ok(out)
}
/// Creates new `ArrayString` from `u16` slice, returning [`Utf16`] on invalid utf-16 data, truncating if bigger than [`capacity`].
///
/// [`Utf16`]: ./error/struct.Utf16.html
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let music = [0xD834, 0xDD1E, 0x006d, 0x0075, 0x0073, 0x0069, 0x0063];
/// let string = SmallString::from_utf16(music)?;
/// assert_eq!(string.as_str(), "𝄞music");
///
/// let invalid_utf16 = [0xD834, 0xDD1E, 0x006d, 0x0075, 0xD800, 0x0069, 0x0063];
/// assert_eq!(SmallString::from_utf16(invalid_utf16), Err(Utf16));
///
/// let out_of_bounds: Vec<u16> = (0..300).map(|_| 0).collect();
/// assert_eq!(SmallString::from_utf16(out_of_bounds)?.as_str(),
/// "\0".repeat(SmallString::capacity().into()).as_str());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn from_utf16<B>(slice: B) -> Result<Self, Utf16>
where
B: AsRef<[u16]>,
{
debug!("From utf16: {:?}", slice.as_ref());
let mut out = Self::default();
for c in decode_utf16(slice.as_ref().iter().cloned()) {
if out.try_push(c?).is_err() {
break;
}
}
Ok(out)
}
/// Creates new `ArrayString` from `u16` slice, replacing invalid utf-16 data with `REPLACEMENT_CHARACTER` (\u{FFFD}) and truncating size if bigger than [`capacity`]
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let music = [0xD834, 0xDD1E, 0x006d, 0x0075, 0x0073, 0x0069, 0x0063];
/// let string = SmallString::from_utf16_lossy(music);
/// assert_eq!(string.as_str(), "𝄞music");
///
/// let invalid_utf16 = [0xD834, 0xDD1E, 0x006d, 0x0075, 0xD800, 0x0069, 0x0063];
/// assert_eq!(SmallString::from_utf16_lossy(invalid_utf16).as_str(), "𝄞mu\u{FFFD}ic");
///
/// let out_of_bounds: Vec<u16> = (0..300).map(|_| 0).collect();
/// assert_eq!(SmallString::from_utf16_lossy(&out_of_bounds).as_str(),
/// "\0".repeat(SmallString::capacity().into()).as_str());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn from_utf16_lossy<B>(slice: B) -> Self
where
B: AsRef<[u16]>,
{
debug!("From utf16 lossy: {:?}", slice.as_ref());
let mut out = Self::default();
for c in decode_utf16(slice.as_ref().iter().cloned()) {
if out.try_push(c.unwrap_or(REPLACEMENT_CHARACTER)).is_err() {
break;
}
}
out
}
/// Extracts a string slice containing the entire `ArrayString`
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let s = SmallString::try_from_str("My String")?;
/// assert_eq!(s.as_str(), "My String");
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn as_str(&self) -> &str {
trace!("As str: {}", <Self as AsRef<str>>::as_ref(self));
self.as_ref()
}
/// Extracts a mutable string slice containing the entire `ArrayString`
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("My String")?;
/// assert_eq!(s.as_mut_str(), "My String");
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn as_mut_str(&mut self) -> &mut str {
trace!("As mut str: {}", self.as_mut());
self.as_mut()
}
/// Extracts a byte slice containing the entire `ArrayString`
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let s = SmallString::try_from_str("My String")?;
/// assert_eq!(s.as_bytes(), "My String".as_bytes());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn as_bytes(&self) -> &[u8] {
trace!("As str: {}", self.as_str());
self.as_ref()
}
/// Extracts a mutable string slice containing the entire `ArrayString`
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// let mut s = SmallString::try_from_str("My String")?;
/// assert_eq!(unsafe { s.as_mut_bytes() }, "My String".as_bytes());
/// # Ok(())
/// # }
/// ```
#[inline]
pub unsafe fn as_mut_bytes(&mut self) -> &mut [u8] {
trace!("As mut str: {}", self.as_str());
let len = self.len();
self.array.as_mut_slice().get_unchecked_mut(..len.into())
}
/// Returns maximum string capacity, defined at compile time, it will never change
///
/// ```rust
/// # use arraystring::prelude::*;
/// # let _ = env_logger::try_init();
/// assert_eq!(ArrayString::<typenum::U32>::capacity(), 32);
/// ```
#[inline]
pub fn capacity() -> u8 {
SIZE::to_u8()
}
/// Pushes string slice to the end of the `ArrayString` if total size is lower or equal to [`capacity`], otherwise returns an error.
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = MaxString::try_from_str("My String")?;
/// s.try_push_str(" My other String")?;
/// assert_eq!(s.as_str(), "My String My other String");
///
/// assert!(s.try_push_str("0".repeat(MaxString::capacity().into())).is_err());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_push_str<S>(&mut self, string: S) -> Result<(), OutOfBounds>
where
S: AsRef<str>,
{
trace!("Push str");
let new_end = string.as_ref().len().saturating_add(self.len().into());
is_inside_boundary(new_end, Self::capacity())?;
unsafe { self.push_str_unchecked(string) };
Ok(())
}
/// Pushes string slice to the end of the `ArrayString` truncating total size if bigger than [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = MaxString::try_from_str("My String")?;
/// s.push_str(" My other String");
/// assert_eq!(s.as_str(), "My String My other String");
///
/// let mut s = SmallString::default();
/// s.push_str("0".repeat(SmallString::capacity() as usize + 1));
/// assert_eq!(s.as_str(), "0".repeat(SmallString::capacity().into()).as_str());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn push_str<S>(&mut self, string: S)
where
S: AsRef<str>,
{
trace!("Push str truncate");
let size = Self::capacity().saturating_sub(self.len());
unsafe { self.push_str_unchecked(truncate_str(string.as_ref(), size)) }
}
/// Pushes string slice to the end of the `ArrayString` assuming total size is appropriate.
///
/// # Safety
///
/// It's UB if `self.len() + string.len()` > [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// let mut s = MaxString::try_from_str("My String")?;
/// unsafe { s.push_str_unchecked(" My other String") };
/// assert_eq!(s.as_str(), "My String My other String");
///
/// // Undefined behavior, don't do it
/// // let mut undefined_behavior = SmallString::default();
/// // undefined_behavior.push_str_unchecked("0".repeat(SmallString::capacity().into() + 1));
/// # Ok(())
/// # }
/// ```
#[inline]
pub unsafe fn push_str_unchecked<S>(&mut self, string: S)
where
S: AsRef<str>,
{
let (s, len) = (string.as_ref(), string.as_ref().len());
debug!("Push str unchecked: {} ({} + {})", s, self.len(), len);
debug_assert!(len.saturating_add(self.len().into()) <= Self::capacity() as usize);
let dest = self.as_mut_bytes().as_mut_ptr().add(self.len().into());
copy_nonoverlapping(s.as_ptr(), dest, len);
self.size = self.size.saturating_add(len.into_lossy());
}
/// Inserts character to the end of the `ArrayString` erroring if total size if bigger than [`capacity`].
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("My String")?;
/// s.try_push('!')?;
/// assert_eq!(s.as_str(), "My String!");
///
/// let mut s = SmallString::try_from_str(&"0".repeat(SmallString::capacity().into()))?;
/// assert!(s.try_push('!').is_err());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_push(&mut self, character: char) -> Result<(), OutOfBounds> {
trace!("Push: {}", character);
let new_end = character.len_utf8().saturating_add(self.len().into());
is_inside_boundary(new_end, Self::capacity())?;
unsafe { self.push_unchecked(character) };
Ok(())
}
/// Inserts character to the end of the `ArrayString` assuming length is appropriate
///
/// # Safety
///
/// It's UB if `self.len() + character.len_utf8()` > [`capacity`]
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// let mut s = SmallString::try_from_str("My String")?;
/// unsafe { s.push_unchecked('!') };
/// assert_eq!(s.as_str(), "My String!");
///
/// // s = SmallString::try_from_str(&"0".repeat(SmallString::capacity().into()))?;
/// // Undefined behavior, don't do it
/// // s.push_unchecked('!');
/// # Ok(())
/// # }
/// ```
#[inline]
pub unsafe fn push_unchecked(&mut self, ch: char) {
let (len, chlen) = (self.len(), ch.len_utf8().into_lossy());
debug!("Push unchecked (len: {}): {} (len: {})", len, ch, chlen);
encode_char_utf8_unchecked(self, ch, len);
self.size = self.size.saturating_add(chlen);
}
/// Truncates `ArrayString` to specified size (if smaller than current size and a valid utf-8 char index).
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("My String")?;
/// s.truncate(5)?;
/// assert_eq!(s.as_str(), "My St");
///
/// // Does nothing
/// s.truncate(6)?;
/// assert_eq!(s.as_str(), "My St");
///
/// // Index is not at a valid char
/// let mut s = SmallString::try_from_str("🤔")?;
/// assert!(s.truncate(1).is_err());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn truncate(&mut self, size: u8) -> Result<(), Utf8> {
debug!("Truncate: {}", size);
let len = min(self.len(), size);
is_char_boundary(self, len).map(|()| self.size = len)
}
/// Removes last character from `ArrayString`, if any.
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("A🤔")?;
/// assert_eq!(s.pop(), Some('🤔'));
/// assert_eq!(s.pop(), Some('A'));
/// assert_eq!(s.pop(), None);
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn pop(&mut self) -> Option<char> {
debug!("Pop");
self.as_str().chars().last().map(|ch| {
self.size = self.size.saturating_sub(ch.len_utf8().into_lossy());
ch
})
}
/// Removes spaces from the beggining and end of the string
///
/// ```rust
/// # use arraystring::prelude::*;
/// # fn main() -> Result<(), OutOfBounds> {
/// # let _ = env_logger::try_init();
/// let mut string = MaxString::try_from_str(" to be trimmed ")?;
/// string.trim();
/// assert_eq!(string.as_str(), "to be trimmed");
///
/// let mut string = SmallString::try_from_str(" 🤔")?;
/// string.trim();
/// assert_eq!(string.as_str(), "🤔");
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn trim(&mut self) {
trace!("Trim");
let is_whitespace = |s: &[u8], index: usize| {
debug_assert!(index < s.len());
unsafe { s.get_unchecked(index) == &b' ' }
};
let (mut start, mut end, mut leave) = (0_u8, self.len(), 0_u8);
while start < end && leave < 2 {
leave = 0;
if is_whitespace(self.as_bytes(), start.into()) {
start = start.saturating_add(1);
if start >= end {
continue;
};
} else {
leave = leave.saturating_add(1);
}
if start < end && is_whitespace(self.as_bytes(), end.saturating_sub(1).into()) {
end = end.saturating_sub(1);
} else {
leave = leave.saturating_add(1);
}
}
unsafe { shift_left_unchecked(self, start, 0u8) };
self.size = end.saturating_sub(start);
}
/// Removes specified char from `ArrayString`
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// assert_eq!(s.remove("ABCD🤔".len() as u8), Err(Error::OutOfBounds));
/// assert_eq!(s.remove(10), Err(Error::OutOfBounds));
/// assert_eq!(s.remove(6), Err(Error::Utf8));
/// assert_eq!(s.remove(0), Ok('A'));
/// assert_eq!(s.as_str(), "BCD🤔");
/// assert_eq!(s.remove(2), Ok('D'));
/// assert_eq!(s.as_str(), "BC🤔");
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn remove(&mut self, idx: u8) -> Result<char, Error> {
debug!("Remove: {}", idx);
is_inside_boundary(idx, self.len().saturating_sub(1))?;
is_char_boundary(self, idx)?;
debug_assert!(idx < self.len() && self.as_str().is_char_boundary(idx.into()));
let ch = unsafe { self.as_str().get_unchecked(idx.into()..).chars().next() };
let ch = ch.unwrap_or_else(|| unsafe { never("Missing char") });
unsafe { shift_left_unchecked(self, idx.saturating_add(ch.len_utf8().into_lossy()), idx) };
self.size = self.size.saturating_sub(ch.len_utf8().into_lossy());
Ok(ch)
}
/// Retains only the characters specified by the predicate.
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// s.retain(|c| c != '🤔');
/// assert_eq!(s.as_str(), "ABCD");
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn retain<F: FnMut(char) -> bool>(&mut self, mut f: F) {
trace!("Retain");
// Not the most efficient solution, we could shift left during batch mismatch
*self = unsafe { Self::from_chars_unchecked(self.as_str().chars().filter(|c| f(*c))) };
}
/// Inserts character at specified index, returning error if total length is bigger than [`capacity`].
///
/// Returns [`OutOfBounds`] if `idx` is out of bounds and [`Utf8`] if `idx` is not a char position
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
/// [`OutOfBounds`]: ./error/enum.Error.html#variant.OutOfBounds
/// [`Utf8`]: ./error/enum.Error.html#variant.Utf8
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// s.try_insert(1, 'A')?;
/// s.try_insert(2, 'B')?;
/// assert_eq!(s.as_str(), "AABBCD🤔");
/// assert_eq!(s.try_insert(20, 'C'), Err(Error::OutOfBounds));
/// assert_eq!(s.try_insert(8, 'D'), Err(Error::Utf8));
///
/// let mut s = SmallString::try_from_str(&"0".repeat(SmallString::capacity().into()))?;
/// assert_eq!(s.try_insert(0, 'C'), Err(Error::OutOfBounds));
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_insert(&mut self, idx: u8, ch: char) -> Result<(), Error> {
trace!("Insert {} to {}", ch, idx);
is_inside_boundary(idx, self.len())?;
let new_end = ch.len_utf8().saturating_add(self.len().into());
is_inside_boundary(new_end, Self::capacity())?;
is_char_boundary(self, idx)?;
unsafe { self.insert_unchecked(idx, ch) };
Ok(())
}
/// Inserts character at specified index assuming length is appropriate
///
/// # Safety
///
/// It's UB if `idx` does not lie on a utf-8 `char` boundary
///
/// It's UB if `self.len() + character.len_utf8()` > [`capacity`]
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// unsafe { s.insert_unchecked(1, 'A') };
/// unsafe { s.insert_unchecked(1, 'B') };
/// assert_eq!(s.as_str(), "ABABCD🤔");
///
/// // Undefined behavior, don't do it
/// // s.insert(20, 'C');
/// // s.insert(8, 'D');
/// # Ok(())
/// # }
/// ```
#[inline]
pub unsafe fn insert_unchecked(&mut self, idx: u8, ch: char) {
let clen = ch.len_utf8().into_lossy();
debug!("Insert uncheck ({}+{}) {} at {}", self.len(), clen, ch, idx);
shift_right_unchecked(self, idx, idx.saturating_add(clen));
encode_char_utf8_unchecked(self, ch, idx);
self.size = self.size.saturating_add(clen);
}
/// Inserts string slice at specified index, returning error if total length is bigger than [`capacity`].
///
/// Returns [`OutOfBounds`] if `idx` is out of bounds
/// Returns [`Utf8`] if `idx` is not a char position
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
/// [`OutOfBounds`]: ./error/enum.Error.html#variant.OutOfBounds
/// [`Utf8`]: ./error/enum.Error.html#variant.Utf8
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// s.try_insert_str(1, "AB")?;
/// s.try_insert_str(1, "BC")?;
/// assert_eq!(s.try_insert_str(1, "0".repeat(SmallString::capacity().into())),
/// Err(Error::OutOfBounds));
/// assert_eq!(s.as_str(), "ABCABBCD🤔");
/// assert_eq!(s.try_insert_str(20, "C"), Err(Error::OutOfBounds));
/// assert_eq!(s.try_insert_str(10, "D"), Err(Error::Utf8));
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn try_insert_str<S>(&mut self, idx: u8, s: S) -> Result<(), Error>
where
S: AsRef<str>,
{
trace!("Try insert str");
is_inside_boundary(idx, self.len())?;
let new_end = s.as_ref().len().saturating_add(self.len().into());
is_inside_boundary(new_end, Self::capacity())?;
is_char_boundary(self, idx)?;
unsafe { self.insert_str_unchecked(idx, s.as_ref()) };
Ok(())
}
/// Inserts string slice at specified index, truncating size if bigger than [`capacity`].
///
/// Returns [`OutOfBounds`] if `idx` is out of bounds and [`Utf8`] if `idx` is not a char position
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
/// [`OutOfBounds`]: ./error/enum.Error.html#variant.OutOfBounds
/// [`Utf8`]: ./error/enum.Error.html#variant.Utf8
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// s.insert_str(1, "AB")?;
/// s.insert_str(1, "BC")?;
/// assert_eq!(s.as_str(), "ABCABBCD🤔");
///
/// assert_eq!(s.insert_str(20, "C"), Err(Error::OutOfBounds));
/// assert_eq!(s.insert_str(10, "D"), Err(Error::Utf8));
///
/// s.clear();
/// s.insert_str(0, "0".repeat(SmallString::capacity() as usize + 10))?;
/// assert_eq!(s.as_str(), "0".repeat(SmallString::capacity().into()).as_str());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn insert_str<S>(&mut self, idx: u8, string: S) -> Result<(), Error>
where
S: AsRef<str>,
{
trace!("Insert str");
is_inside_boundary(idx, self.len())?;
is_char_boundary(self, idx)?;
let size = Self::capacity().saturating_sub(self.len());
unsafe { self.insert_str_unchecked(idx, truncate_str(string.as_ref(), size)) };
Ok(())
}
/// Inserts string slice at specified index, assuming total length is appropriate.
///
/// # Safety
///
/// It's UB if `idx` does not lie on a utf-8 `char` boundary
///
/// It's UB if `self.len() + string.len()` > [`capacity`]
///
/// [`capacity`]: ./struct.ArrayString.html#method.capacity
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// unsafe { s.insert_str_unchecked(1, "AB") };
/// unsafe { s.insert_str_unchecked(1, "BC") };
/// assert_eq!(s.as_str(), "ABCABBCD🤔");
///
/// // Undefined behavior, don't do it
/// // unsafe { s.insert_str_unchecked(20, "C") };
/// // unsafe { s.insert_str_unchecked(10, "D") };
/// // unsafe { s.insert_str_unchecked(1, "0".repeat(SmallString::capacity().into())) };
/// # Ok(())
/// # }
/// ```
#[inline]
pub unsafe fn insert_str_unchecked<S>(&mut self, idx: u8, string: S)
where
S: AsRef<str>,
{
let (s, slen) = (string.as_ref(), string.as_ref().len().into_lossy());
let ptr = s.as_ptr();
trace!("InsertStr uncheck {}+{} {} at {}", self.len(), slen, s, idx);
debug_assert!(self.len().saturating_add(slen) <= Self::capacity());
debug_assert!(idx <= self.len());
debug_assert!(self.as_str().is_char_boundary(idx.into()));
shift_right_unchecked(self, idx, idx.saturating_add(slen));
let dest = self.as_mut_bytes().as_mut_ptr().add(idx.into());
copy_nonoverlapping(ptr, dest, slen.into());
self.size = self.size.saturating_add(slen);
}
/// Returns `ArrayString` length.
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD")?;
/// assert_eq!(s.len(), 4);
/// s.try_push('🤔')?;
/// // Emojis use 4 bytes (this is the default rust behavior, length of u8)
/// assert_eq!(s.len(), 8);
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn len(&self) -> u8 {
trace!("Len");
self.size
}
/// Checks if `ArrayString` is empty.
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD")?;
/// assert!(!s.is_empty());
/// s.clear();
/// assert!(s.is_empty());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn is_empty(&self) -> bool {
trace!("Is empty");
self.len() == 0
}
/// Splits `ArrayString` in two if `at` is smaller than `self.len()`.
///
/// Returns [`Utf8`] if `at` does not lie at a valid utf-8 char boundary and [`OutOfBounds`] if it's out of bounds
///
/// [`OutOfBounds`]: ./error/enum.Error.html#variant.OutOfBounds
/// [`Utf8`]: ./error/enum.Error.html#variant.Utf8
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("AB🤔CD")?;
/// assert_eq!(s.split_off(6)?.as_str(), "CD");
/// assert_eq!(s.as_str(), "AB🤔");
/// assert_eq!(s.split_off(20), Err(Error::OutOfBounds));
/// assert_eq!(s.split_off(4), Err(Error::Utf8));
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn split_off(&mut self, at: u8) -> Result<Self, Error> {
debug!("Split off");
is_inside_boundary(at, self.len())?;
is_char_boundary(self, at)?;
debug_assert!(at <= self.len() && self.as_str().is_char_boundary(at.into()));
let new = unsafe { Self::from_utf8_unchecked(self.as_str().get_unchecked(at.into()..)) };
self.size = at;
Ok(new)
}
/// Empties `ArrayString`
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD")?;
/// assert!(!s.is_empty());
/// s.clear();
/// assert!(s.is_empty());
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn clear(&mut self) {
trace!("Clear");
self.size = 0;
}
/// Creates a draining iterator that removes the specified range in the `ArrayString` and yields the removed chars.
///
/// Note: The element range is removed even if the iterator is not consumed until the end.
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// assert_eq!(s.drain(..3)?.collect::<Vec<_>>(), vec!['A', 'B', 'C']);
/// assert_eq!(s.as_str(), "D🤔");
///
/// assert_eq!(s.drain(3..), Err(Error::Utf8));
/// assert_eq!(s.drain(10..), Err(Error::OutOfBounds));
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn drain<R>(&mut self, range: R) -> Result<Drain<SIZE>, Error>
where
R: RangeBounds<u8>,
{
let start = match range.start_bound() {
Bound::Included(t) => *t,
Bound::Excluded(t) => t.saturating_add(1),
Bound::Unbounded => 0,
};
let end = match range.end_bound() {
Bound::Included(t) => t.saturating_add(1),
Bound::Excluded(t) => *t,
Bound::Unbounded => self.len(),
};
debug!("Drain iterator (len: {}): {}..{}", self.len(), start, end);
is_inside_boundary(start, end)?;
is_inside_boundary(end, self.len())?;
is_char_boundary(self, start)?;
is_char_boundary(self, end)?;
debug_assert!(start <= end && end <= self.len());
debug_assert!(self.as_str().is_char_boundary(start.into()));
debug_assert!(self.as_str().is_char_boundary(end.into()));
let drain = unsafe {
let slice = self.as_str().get_unchecked(start.into()..end.into());
Self::from_str_unchecked(slice)
};
unsafe { shift_left_unchecked(self, end, start) };
self.size = self.size.saturating_sub(end.saturating_sub(start));
Ok(Drain(drain, 0))
}
/// Removes the specified range of the `ArrayString`, and replaces it with the given string. The given string doesn't need to have the same length as the range.
///
/// ```rust
/// # use arraystring::{error::Error, prelude::*};
/// # fn main() -> Result<(), Error> {
/// # let _ = env_logger::try_init();
/// let mut s = SmallString::try_from_str("ABCD🤔")?;
/// s.replace_range(2..4, "EFGHI")?;
/// assert_eq!(s.as_str(), "ABEFGHI🤔");
///
/// assert_eq!(s.replace_range(9.., "J"), Err(Error::Utf8));
/// assert_eq!(s.replace_range(..90, "K"), Err(Error::OutOfBounds));
/// assert_eq!(s.replace_range(0..1, "0".repeat(SmallString::capacity().into())),
/// Err(Error::OutOfBounds));
/// # Ok(())
/// # }
/// ```
#[inline]
pub fn replace_range<S, R>(&mut self, r: R, with: S) -> Result<(), Error>
where
S: AsRef<str>,
R: RangeBounds<u8>,
{
let replace_with = with.as_ref();
let start = match r.start_bound() {
Bound::Included(t) => *t,
Bound::Excluded(t) => t.saturating_add(1),
Bound::Unbounded => 0,
};
let end = match r.end_bound() {
Bound::Included(t) => t.saturating_add(1),
Bound::Excluded(t) => *t,
Bound::Unbounded => self.len(),
};
let len = replace_with.len().into_lossy();
debug!(
"Replace range (len: {}) ({}..{}) with (len: {}) {}",
self.len(),
start,
end,
len,
replace_with
);
is_inside_boundary(start, end)?;
is_inside_boundary(end, self.len())?;
let replaced = (end as usize).saturating_sub(start.into());
is_inside_boundary(replaced.saturating_add(len.into()), Self::capacity())?;
is_char_boundary(self, start)?;
is_char_boundary(self, end)?;
debug_assert!(start <= end && end <= self.len());
debug_assert!(len.saturating_sub(end).saturating_add(start) <= Self::capacity());
debug_assert!(self.as_str().is_char_boundary(start.into()));
debug_assert!(self.as_str().is_char_boundary(end.into()));
if start.saturating_add(len) > end {
unsafe { shift_right_unchecked(self, end, start.saturating_add(len)) };
} else {
unsafe { shift_left_unchecked(self, end, start.saturating_add(len)) };
}
let grow = len.saturating_sub(replaced.into_lossy());
self.size = self.size.saturating_add(grow);
let ptr = replace_with.as_ptr();
let dest = unsafe { self.as_mut_bytes().as_mut_ptr().add(start.into()) };
unsafe { copy_nonoverlapping(ptr, dest, len.into()) };
Ok(())
}
}