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//! Implementation of [`SmartDisplay`] for various types.
#[cfg(feature = "alloc")]
use alloc::borrow::{Cow, ToOwned};
#[cfg(feature = "alloc")]
use alloc::boxed::Box;
#[cfg(feature = "alloc")]
use alloc::rc::Rc;
#[cfg(feature = "alloc")]
use alloc::string::String;
#[cfg(feature = "alloc")]
use alloc::sync::Arc;
use core::cell::{Ref, RefMut};
use core::cmp::min;
use core::convert::Infallible;
use core::fmt::{self, Display, Formatter};
use core::num::Wrapping;
use core::pin::Pin;
use crate::smart_display::{FormatterOptions, Metadata, SmartDisplay};
impl SmartDisplay for Infallible {
type Metadata = Self;
#[inline]
fn metadata(&self, _: FormatterOptions) -> Metadata<'_, Self> {
match *self {}
}
#[inline]
fn fmt(&self, _: &mut Formatter<'_>) -> fmt::Result {
match *self {}
}
}
impl SmartDisplay for bool {
type Metadata = ();
#[inline]
fn metadata(&self, _: FormatterOptions) -> Metadata<'_, Self> {
Metadata::new(if *self { 4 } else { 5 }, self, ())
}
#[inline]
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}
impl SmartDisplay for str {
type Metadata = ();
#[inline]
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
Metadata::new(
match f.precision() {
Some(max_len) => min(self.len(), max_len),
None => self.len(),
},
self,
(),
)
}
#[inline]
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}
#[cfg(feature = "alloc")]
impl SmartDisplay for String {
type Metadata = ();
#[inline]
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
#[inline]
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}
#[cfg(feature = "alloc")]
impl<'a, B, O> SmartDisplay for Cow<'a, B>
where
B: SmartDisplay + ToOwned<Owned = O> + ?Sized,
O: SmartDisplay<Metadata = B::Metadata> + 'a,
{
type Metadata = B::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
match *self {
Cow::Borrowed(ref b) => b.metadata(f).reuse(),
Cow::Owned(ref o) => o.metadata(f).reuse(),
}
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}
impl<T> SmartDisplay for Pin<&T>
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
self.get_ref().metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(self.get_ref(), f)
}
}
impl<T> SmartDisplay for &T
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(*self, f)
}
}
impl<T> SmartDisplay for &mut T
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(*self, f)
}
}
impl<T> SmartDisplay for Ref<'_, T>
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(&**self, f)
}
}
impl<T> SmartDisplay for RefMut<'_, T>
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(&**self, f)
}
}
impl<T> SmartDisplay for Wrapping<T>
where
T: SmartDisplay,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
self.0.metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(&self.0, f)
}
}
#[cfg(feature = "alloc")]
impl<T> SmartDisplay for Rc<T>
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(&**self, f)
}
}
#[cfg(feature = "alloc")]
impl<T> SmartDisplay for Arc<T>
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(&**self, f)
}
}
#[cfg(feature = "alloc")]
impl<T> SmartDisplay for Box<T>
where
T: SmartDisplay + ?Sized,
{
type Metadata = T::Metadata;
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
(**self).metadata(f).reuse()
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
SmartDisplay::fmt(&**self, f)
}
}
/// Implement [`SmartDisplay`] for unsigned integers.
macro_rules! impl_uint {
($($t:ty)*) => {$(
impl SmartDisplay for $t {
type Metadata = ();
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
let mut width = self.checked_ilog10().map_or(1, |n| n as usize + 1);
if f.sign_plus() || f.sign_minus() {
width += 1;
}
Metadata::new(width, self, ())
}
#[inline]
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}
)*};
}
impl_uint![u8 u16 u32 u64 u128 usize];
/// Implement [`SmartDisplay`] for signed integers.
macro_rules! impl_int {
($($t:ty)*) => {$(
impl SmartDisplay for $t {
type Metadata = ();
fn metadata(&self, f: FormatterOptions) -> Metadata<'_, Self> {
let mut width = if f.sign_plus() || *self < 0 { 1 } else { 0 };
width += self.unsigned_abs().checked_ilog10().map_or(1, |n| n as usize + 1);
Metadata::new(width, self, ())
}
#[inline]
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}
)*};
}
impl_int![i8 i16 i32 i64 i128 isize];
impl SmartDisplay for char {
type Metadata = ();
fn metadata(&self, _: FormatterOptions) -> Metadata<'_, Self> {
let mut buf = [0; 4];
let c = self.encode_utf8(&mut buf);
Metadata::new(c.len(), self, ())
}
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}