bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'lib/text-size/src/size.rs')
-rw-r--r--lib/text-size/src/size.rs41
1 files changed, 29 insertions, 12 deletions
diff --git a/lib/text-size/src/size.rs b/lib/text-size/src/size.rs
index 454327a015..5239ea6691 100644
--- a/lib/text-size/src/size.rs
+++ b/lib/text-size/src/size.rs
@@ -11,15 +11,23 @@ use {
/// A measure of text length. Also, equivalently, an index into text.
///
-/// This is a utf8-bytes-offset stored as `u32`, but
+/// This is a UTF-8 bytes offset stored as `u32`, but
/// most clients should treat it as an opaque measure.
///
+/// For cases that need to escape `TextSize` and return to working directly
+/// with primitive integers, `TextSize` can be converted losslessly to/from
+/// `u32` via [`From`] conversions as well as losslessly be converted [`Into`]
+/// `usize`. The `usize -> TextSize` direction can be done via [`TryFrom`].
+///
+/// These escape hatches are primarily required for unit testing and when
+/// converting from UTF-8 size to another coordinate space, such as UTF-16.
+///
/// # Translation from `text_unit`
///
/// - `TextUnit::of_char(c)` ⟹ `TextSize::of(c)`
-/// - `TextUnit::of_str(s)` ⟹ `TextSize:of(s)`
+/// - `TextUnit::of_str(s)` ⟹ `TextSize::of(s)`
/// - `TextUnit::from_usize(size)` ⟹ `TextSize::try_from(size).unwrap_or_else(|| panic!(_))`
-/// - `unit.to_usize()` ⟹ `usize::try_from(size).unwrap_or_else(|| panic!(_))`
+/// - `unit.to_usize()` ⟹ `usize::from(size)`
#[derive(Clone, Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct TextSize {
pub(crate) raw: u32,
@@ -38,6 +46,7 @@ impl fmt::Debug for TextSize {
impl TextSize {
/// The text size of some text-like object.
+ #[inline]
pub fn of(text: impl TextSized) -> TextSize {
text.text_size()
}
@@ -46,6 +55,7 @@ impl TextSize {
///
/// This is equivalent to `TextSize::default()` or [`TextSize::MIN`],
/// but is more explicit on intent.
+ #[inline]
pub const fn zero() -> TextSize {
TextSize(0)
}
@@ -59,24 +69,28 @@ impl TextSize {
/// The largest representable text size. (`u32::MAX`)
pub const MAX: TextSize = TextSize(u32::MAX);
- #[allow(missing_docs)]
+ /// Checked addition. Returns `None` if overflow occurred.
+ #[inline]
pub fn checked_add(self, rhs: TextSize) -> Option<TextSize> {
self.raw.checked_add(rhs.raw).map(TextSize)
}
- #[allow(missing_docs)]
+ /// Checked subtraction. Returns `None` if overflow occurred.
+ #[inline]
pub fn checked_sub(self, rhs: TextSize) -> Option<TextSize> {
self.raw.checked_sub(rhs.raw).map(TextSize)
}
}
impl From<u32> for TextSize {
+ #[inline]
fn from(raw: u32) -> Self {
- TextSize { raw }
+ TextSize(raw)
}
}
impl From<TextSize> for u32 {
+ #[inline]
fn from(value: TextSize) -> Self {
value.raw
}
@@ -84,19 +98,16 @@ impl From<TextSize> for u32 {
impl TryFrom<usize> for TextSize {
type Error = TryFromIntError;
+ #[inline]
fn try_from(value: usize) -> Result<Self, TryFromIntError> {
Ok(u32::try_from(value)?.into())
}
}
impl From<TextSize> for usize {
+ #[inline]
fn from(value: TextSize) -> Self {
- assert_lossless_conversion();
- return value.raw as usize;
-
- const fn assert_lossless_conversion() {
- [()][(std::mem::size_of::<usize>() < std::mem::size_of::<u32>()) as usize]
- }
+ value.raw as usize
}
}
@@ -104,12 +115,14 @@ macro_rules! ops {
(impl $Op:ident for TextSize by fn $f:ident = $op:tt) => {
impl $Op<TextSize> for TextSize {
type Output = TextSize;
+ #[inline]
fn $f(self, other: TextSize) -> TextSize {
TextSize(self.raw $op other.raw)
}
}
impl $Op<&TextSize> for TextSize {
type Output = TextSize;
+ #[inline]
fn $f(self, other: &TextSize) -> TextSize {
self $op *other
}
@@ -119,6 +132,7 @@ macro_rules! ops {
TextSize: $Op<T, Output=TextSize>,
{
type Output = TextSize;
+ #[inline]
fn $f(self, other: T) -> TextSize {
*self $op other
}
@@ -133,6 +147,7 @@ impl<A> AddAssign<A> for TextSize
where
TextSize: Add<A, Output = TextSize>,
{
+ #[inline]
fn add_assign(&mut self, rhs: A) {
*self = *self + rhs
}
@@ -142,6 +157,7 @@ impl<S> SubAssign<S> for TextSize
where
TextSize: Sub<S, Output = TextSize>,
{
+ #[inline]
fn sub_assign(&mut self, rhs: S) {
*self = *self - rhs
}
@@ -151,6 +167,7 @@ impl<A> iter::Sum<A> for TextSize
where
TextSize: Add<A, Output = TextSize>,
{
+ #[inline]
fn sum<I: Iterator<Item = A>>(iter: I) -> TextSize {
iter.fold(TextSize::zero(), Add::add)
}