Merge tag 'debian/1.52.1+dfsg1-1_exp2' into proxmox/buster

[rustc.git] / library / std / src / ffi / os_str.rs

diff --git a/library/std/src/ffi/os_str.rs b/library/std/src/ffi/os_str.rs
index c9c8f68cd9cce7069b0eeec5922de019bf9145cc..ce52ffc0241b04802c53e44b51119ceb09de659b 100644 (file)
--- 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;
@@ -71,11 +72,16 @@ use crate::sys_common::{AsInner, FromInner, IntoInner};
 /// [`CStr`]: crate::ffi::CStr
 /// [conversions]: super#conversions
 #[derive(Clone)]
+#[cfg_attr(not(test), rustc_diagnostic_item = "OsString")]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct OsString {
     inner: Buf,
 }
 
+/// Allows extension traits within `std`.
+#[unstable(feature = "sealed", issue = "none")]
+impl crate::sealed::Sealed for OsString {}
+
 /// Borrowed reference to an OS string (see [`OsString`]).
 ///
 /// This type represents a borrowed reference to a string in the operating system's preferred
@@ -89,6 +95,7 @@ pub struct OsString {
 ///
 /// [`&str`]: str
 /// [conversions]: super#conversions
+#[cfg_attr(not(test), rustc_diagnostic_item = "OsStr")]
 #[stable(feature = "rust1", since = "1.0.0")]
 // FIXME:
 // `OsStr::from_inner` current implementation relies
@@ -100,6 +107,10 @@ pub struct OsStr {
     inner: Slice,
 }
 
+/// Allows extension traits within `std`.
+#[unstable(feature = "sealed", issue = "none")]
+impl crate::sealed::Sealed for OsStr {}
+
 impl OsString {
     /// Constructs a new empty `OsString`.
     ///
@@ -1182,3 +1193,88 @@ impl FromStr for OsString {
         Ok(OsString::from(s))
     }
 }
+
+#[stable(feature = "osstring_extend", since = "1.52.0")]
+impl Extend<OsString> for OsString {
+    #[inline]
+    fn extend<T: IntoIterator<Item = OsString>>(&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<T: IntoIterator<Item = &'a OsStr>>(&mut self, iter: T) {
+        for s in iter {
+            self.push(s);
+        }
+    }
+}
+
+#[stable(feature = "osstring_extend", since = "1.52.0")]
+impl<'a> Extend<Cow<'a, OsStr>> for OsString {
+    #[inline]
+    fn extend<T: IntoIterator<Item = Cow<'a, OsStr>>>(&mut self, iter: T) {
+        for s in iter {
+            self.push(&s);
+        }
+    }
+}
+
+#[stable(feature = "osstring_extend", since = "1.52.0")]
+impl FromIterator<OsString> for OsString {
+    #[inline]
+    fn from_iter<I: IntoIterator<Item = OsString>>(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<I: IntoIterator<Item = &'a OsStr>>(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<Cow<'a, OsStr>> for OsString {
+    #[inline]
+    fn from_iter<I: IntoIterator<Item = Cow<'a, OsStr>>>(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
+            }
+        }
+    }
+}