bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

shrink_to shouldn't panic on len greater than capacity

Browse source
This commit is contained in:
Thom Wiggers 2021-01-24 13:29:39 +01:00
parent 85e355ea9b
commit d069c58e78
No known key found for this signature in database
GPG key ID: 001BB0A7CE26E363
8 changed files with 15 additions and 32 deletions
Download patch file Download diff file Expand all files Collapse all files

12
library/alloc/src/vec/mod.rs
View file

@ -321,7 +321,7 @@ mod spec_extend;
/// ensures no unnecessary allocations or deallocations occur. Emptying a `Vec`
/// and then filling it back up to the same [`len`] should incur no calls to
/// the allocator. If you wish to free up unused memory, use
/// [`shrink_to_fit`].
/// [`shrink_to_fit`] or [`shrink_to`].
///
/// [`push`] and [`insert`] will never (re)allocate if the reported capacity is
/// sufficient. [`push`] and [`insert`] *will* (re)allocate if
@ -360,6 +360,7 @@ mod spec_extend;
/// [`String`]: crate::string::String
/// [`&str`]: type@str
/// [`shrink_to_fit`]: Vec::shrink_to_fit
/// [`shrink_to`]: Vec::shrink_to
/// [`capacity`]: Vec::capacity
/// [`mem::size_of::<T>`]: core::mem::size_of
/// [`len`]: Vec::len
@ -909,10 +910,7 @@ impl<T, A: Allocator> Vec<T, A> {
/// The capacity will remain at least as large as both the length
/// and the supplied value.
///
/// # Panics
///
/// Panics if the current capacity is smaller than the supplied
/// minimum capacity.
/// If the current capacity is less than the lower limit, this is a no-op.
///
/// # Examples
///
@ -929,7 +927,9 @@ impl<T, A: Allocator> Vec<T, A> {
#[doc(alias = "realloc")]
#[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
pub fn shrink_to(&mut self, min_capacity: usize) {
self.buf.shrink_to_fit(cmp::max(self.len, min_capacity));
if self.capacity() > min_capacity {
self.buf.shrink_to_fit(cmp::max(self.len, min_capacity));
}
}
/// Converts the vector into [`Box<[T]>`][owned slice].