diff --git a/library/std/src/ffi/os_str.rs b/library/std/src/ffi/os_str.rs index c9c8f68cd9cce..8bdd9a88473f9 100644 --- a/library/std/src/ffi/os_str.rs +++ b/library/std/src/ffi/os_str.rs @@ -5,6 +5,7 @@ use crate::borrow::{Borrow, Cow}; use crate::cmp; use crate::fmt; use crate::hash::{Hash, Hasher}; +use crate::iter::{Extend, FromIterator}; use crate::ops; use crate::rc::Rc; use crate::str::FromStr; @@ -1182,3 +1183,88 @@ impl FromStr for OsString { Ok(OsString::from(s)) } } + +#[stable(feature = "osstring_extend", since = "1.52.0")] +impl Extend for OsString { + #[inline] + fn extend>(&mut self, iter: T) { + for s in iter { + self.push(&s); + } + } +} + +#[stable(feature = "osstring_extend", since = "1.52.0")] +impl<'a> Extend<&'a OsStr> for OsString { + #[inline] + fn extend>(&mut self, iter: T) { + for s in iter { + self.push(s); + } + } +} + +#[stable(feature = "osstring_extend", since = "1.52.0")] +impl<'a> Extend> for OsString { + #[inline] + fn extend>>(&mut self, iter: T) { + for s in iter { + self.push(&s); + } + } +} + +#[stable(feature = "osstring_extend", since = "1.52.0")] +impl FromIterator for OsString { + #[inline] + fn from_iter>(iter: I) -> Self { + let mut iterator = iter.into_iter(); + + // Because we're iterating over `OsString`s, we can avoid at least + // one allocation by getting the first string from the iterator + // and appending to it all the subsequent strings. + match iterator.next() { + None => OsString::new(), + Some(mut buf) => { + buf.extend(iterator); + buf + } + } + } +} + +#[stable(feature = "osstring_extend", since = "1.52.0")] +impl<'a> FromIterator<&'a OsStr> for OsString { + #[inline] + fn from_iter>(iter: I) -> Self { + let mut buf = Self::new(); + for s in iter { + buf.push(s); + } + buf + } +} + +#[stable(feature = "osstring_extend", since = "1.52.0")] +impl<'a> FromIterator> for OsString { + #[inline] + fn from_iter>>(iter: I) -> Self { + let mut iterator = iter.into_iter(); + + // Because we're iterating over `OsString`s, we can avoid at least + // one allocation by getting the first owned string from the iterator + // and appending to it all the subsequent strings. + match iterator.next() { + None => OsString::new(), + Some(Cow::Owned(mut buf)) => { + buf.extend(iterator); + buf + } + Some(Cow::Borrowed(buf)) => { + let mut buf = OsString::from(buf); + buf.extend(iterator); + buf + } + } + } +}