Skip to content

Commit 71d7b29

Browse files
borsbors
committed
Auto merge of #40009 - clarcharr:box_to_buf, r=alexcrichton
Leftovers from #39594; From<Box> impls These are a few more impls that follow the same reasoning as those from #39594. What's included: * `From<Box<str>> for String` * `From<Box<[T]>> for Vec<T>` * `From<Box<CStr>> for CString` * `From<Box<OsStr>> for OsString` * `From<Box<Path>> for PathBuf` * `Into<Box<str>> for String` * `Into<Box<[T]>> for Vec<T>` * `Into<Box<CStr>> for CString` * `Into<Box<OsStr>> for OsString` * `Into<Box<Path>> for PathBuf` * `<Box<CStr>>::into_c_string` * `<Box<OsStr>>::into_os_string` * `<Box<Path>>::into_path_buf` * Tracking issue for latter three methods + three from previous PR. Currently, the opposite direction isn't doable with `From` (only `Into`) because of the separation between `liballoc` and `libcollections`. I'm holding off on those for a later PR.
2 parents 6f10e2f + 560944b commit 71d7b29

File tree

9 files changed

+136
-21
lines changed

9 files changed

+136
-21
lines changed

‎src/libcollections/string.rs

+16
Original file line numberDiff line numberDiff line change
@@ -1974,6 +1974,22 @@ impl<'a> From<&'a str> for String {
19741974
}
19751975
}
19761976

1977+
// note: test pulls in libstd, which causes errors here
1978+
#[cfg(not(test))]
1979+
#[stable(feature = "string_from_box", since = "1.17.0")]
1980+
impl From<Box<str>> for String {
1981+
fn from(s: Box<str>) -> String {
1982+
s.into_string()
1983+
}
1984+
}
1985+
1986+
#[stable(feature = "box_from_str", since = "1.17.0")]
1987+
impl Into<Box<str>> for String {
1988+
fn into(self) -> Box<str> {
1989+
self.into_boxed_str()
1990+
}
1991+
}
1992+
19771993
#[stable(feature = "string_from_cow_str", since = "1.14.0")]
19781994
impl<'a> From<Cow<'a, str>> for String {
19791995
fn from(s: Cow<'a, str>) -> String {

‎src/libcollections/vec.rs

+16
Original file line numberDiff line numberDiff line change
@@ -1897,6 +1897,22 @@ impl<'a, T> From<Cow<'a, [T]>> for Vec<T> where [T]: ToOwned<Owned=Vec<T>> {
18971897
}
18981898
}
18991899

1900+
// note: test pulls in libstd, which causes errors here
1901+
#[cfg(not(test))]
1902+
#[stable(feature = "vec_from_box", since = "1.17.0")]
1903+
impl<T> From<Box<[T]>> for Vec<T> {
1904+
fn from(s: Box<[T]>) -> Vec<T> {
1905+
s.into_vec()
1906+
}
1907+
}
1908+
1909+
#[stable(feature = "box_from_vec", since = "1.17.0")]
1910+
impl<T> Into<Box<[T]>> for Vec<T> {
1911+
fn into(self) -> Box<[T]> {
1912+
self.into_boxed_slice()
1913+
}
1914+
}
1915+
19001916
#[stable(feature = "rust1", since = "1.0.0")]
19011917
impl<'a> From<&'a str> for Vec<u8> {
19021918
fn from(s: &'a str) -> Vec<u8> {

‎src/libstd/ffi/c_str.rs

+26-7
Original file line numberDiff line numberDiff line change
@@ -325,7 +325,7 @@ impl CString {
325325
}
326326

327327
/// Converts this `CString` into a boxed `CStr`.
328-
#[unstable(feature = "into_boxed_c_str", issue = "0")]
328+
#[unstable(feature = "into_boxed_c_str", issue = "40380")]
329329
pub fn into_boxed_c_str(self) -> Box<CStr> {
330330
unsafe { mem::transmute(self.into_inner()) }
331331
}
@@ -415,6 +415,20 @@ impl<'a> From<&'a CStr> for Box<CStr> {
415415
}
416416
}
417417

418+
#[stable(feature = "c_string_from_box", since = "1.17.0")]
419+
impl From<Box<CStr>> for CString {
420+
fn from(s: Box<CStr>) -> CString {
421+
s.into_c_string()
422+
}
423+
}
424+
425+
#[stable(feature = "box_from_c_string", since = "1.17.0")]
426+
impl Into<Box<CStr>> for CString {
427+
fn into(self) -> Box<CStr> {
428+
self.into_boxed_c_str()
429+
}
430+
}
431+
418432
#[stable(feature = "default_box_extra", since = "1.17.0")]
419433
impl Default for Box<CStr> {
420434
fn default() -> Box<CStr> {
@@ -728,6 +742,12 @@ impl CStr {
728742
pub fn to_string_lossy(&self) -> Cow<str> {
729743
String::from_utf8_lossy(self.to_bytes())
730744
}
745+
746+
/// Converts a `Box<CStr>` into a `CString` without copying or allocating.
747+
#[unstable(feature = "into_boxed_c_str", issue = "40380")]
748+
pub fn into_c_string(self: Box<CStr>) -> CString {
749+
unsafe { mem::transmute(self) }
750+
}
731751
}
732752

733753
#[stable(feature = "rust1", since = "1.0.0")]
@@ -922,12 +942,11 @@ mod tests {
922942
fn into_boxed() {
923943
let orig: &[u8] = b"Hello, world!\0";
924944
let cstr = CStr::from_bytes_with_nul(orig).unwrap();
925-
let cstring = cstr.to_owned();
926-
let box1: Box<CStr> = Box::from(cstr);
927-
let box2 = cstring.into_boxed_c_str();
928-
assert_eq!(cstr, &*box1);
929-
assert_eq!(box1, box2);
930-
assert_eq!(&*box2, cstr);
945+
let boxed: Box<CStr> = Box::from(cstr);
946+
let cstring = cstr.to_owned().into_boxed_c_str().into_c_string();
947+
assert_eq!(cstr, &*boxed);
948+
assert_eq!(&*boxed, &*cstring);
949+
assert_eq!(&*cstring, cstr);
931950
}
932951

933952
#[test]

‎src/libstd/ffi/os_str.rs

+27-7
Original file line numberDiff line numberDiff line change
@@ -212,7 +212,7 @@ impl OsString {
212212
}
213213

214214
/// Converts this `OsString` into a boxed `OsStr`.
215-
#[unstable(feature = "into_boxed_os_str", issue = "0")]
215+
#[unstable(feature = "into_boxed_os_str", issue = "40380")]
216216
pub fn into_boxed_os_str(self) -> Box<OsStr> {
217217
unsafe { mem::transmute(self.inner.into_box()) }
218218
}
@@ -448,6 +448,13 @@ impl OsStr {
448448
self.inner.inner.len()
449449
}
450450

451+
/// Converts a `Box<OsStr>` into an `OsString` without copying or allocating.
452+
#[unstable(feature = "into_boxed_os_str", issue = "40380")]
453+
pub fn into_os_string(self: Box<OsStr>) -> OsString {
454+
let inner: Box<Slice> = unsafe { mem::transmute(self) };
455+
OsString { inner: Buf::from_box(inner) }
456+
}
457+
451458
/// Gets the underlying byte representation.
452459
///
453460
/// Note: it is *crucial* that this API is private, to avoid
@@ -464,6 +471,20 @@ impl<'a> From<&'a OsStr> for Box<OsStr> {
464471
}
465472
}
466473

474+
#[stable(feature = "os_string_from_box", since = "1.17.0")]
475+
impl<'a> From<Box<OsStr>> for OsString {
476+
fn from(boxed: Box<OsStr>) -> OsString {
477+
boxed.into_os_string()
478+
}
479+
}
480+
481+
#[stable(feature = "box_from_c_string", since = "1.17.0")]
482+
impl Into<Box<OsStr>> for OsString {
483+
fn into(self) -> Box<OsStr> {
484+
self.into_boxed_os_str()
485+
}
486+
}
487+
467488
#[stable(feature = "box_default_extra", since = "1.17.0")]
468489
impl Default for Box<OsStr> {
469490
fn default() -> Box<OsStr> {
@@ -772,12 +793,11 @@ mod tests {
772793
fn into_boxed() {
773794
let orig = "Hello, world!";
774795
let os_str = OsStr::new(orig);
775-
let os_string = os_str.to_owned();
776-
let box1: Box<OsStr> = Box::from(os_str);
777-
let box2 = os_string.into_boxed_os_str();
778-
assert_eq!(os_str, &*box1);
779-
assert_eq!(box1, box2);
780-
assert_eq!(&*box2, os_str);
796+
let boxed: Box<OsStr> = Box::from(os_str);
797+
let os_string = os_str.to_owned().into_boxed_os_str().into_os_string();
798+
assert_eq!(os_str, &*boxed);
799+
assert_eq!(&*boxed, &*os_string);
800+
assert_eq!(&*os_string, os_str);
781801
}
782802

783803
#[test]

‎src/libstd/path.rs

+27-7
Original file line numberDiff line numberDiff line change
@@ -1196,7 +1196,7 @@ impl PathBuf {
11961196
}
11971197

11981198
/// Converts this `PathBuf` into a boxed `Path`.
1199-
#[unstable(feature = "into_boxed_path", issue = "0")]
1199+
#[unstable(feature = "into_boxed_path", issue = "40380")]
12001200
pub fn into_boxed_path(self) -> Box<Path> {
12011201
unsafe { mem::transmute(self.inner.into_boxed_os_str()) }
12021202
}
@@ -1210,6 +1210,20 @@ impl<'a> From<&'a Path> for Box<Path> {
12101210
}
12111211
}
12121212

1213+
#[stable(feature = "path_buf_from_box", since = "1.17.0")]
1214+
impl<'a> From<Box<Path>> for PathBuf {
1215+
fn from(boxed: Box<Path>) -> PathBuf {
1216+
boxed.into_path_buf()
1217+
}
1218+
}
1219+
1220+
#[stable(feature = "box_from_path_buf", since = "1.17.0")]
1221+
impl Into<Box<Path>> for PathBuf {
1222+
fn into(self) -> Box<Path> {
1223+
self.into_boxed_path()
1224+
}
1225+
}
1226+
12131227
#[stable(feature = "box_default_extra", since = "1.17.0")]
12141228
impl Default for Box<Path> {
12151229
fn default() -> Box<Path> {
@@ -2089,6 +2103,13 @@ impl Path {
20892103
pub fn is_dir(&self) -> bool {
20902104
fs::metadata(self).map(|m| m.is_dir()).unwrap_or(false)
20912105
}
2106+
2107+
/// Converts a `Box<Path>` into a `PathBuf` without copying or allocating.
2108+
#[unstable(feature = "into_boxed_path", issue = "40380")]
2109+
pub fn into_path_buf(self: Box<Path>) -> PathBuf {
2110+
let inner: Box<OsStr> = unsafe { mem::transmute(self) };
2111+
PathBuf { inner: OsString::from(inner) }
2112+
}
20922113
}
20932114

20942115
#[stable(feature = "rust1", since = "1.0.0")]
@@ -3703,12 +3724,11 @@ mod tests {
37033724
fn into_boxed() {
37043725
let orig: &str = "some/sort/of/path";
37053726
let path = Path::new(orig);
3706-
let path_buf = path.to_owned();
3707-
let box1: Box<Path> = Box::from(path);
3708-
let box2 = path_buf.into_boxed_path();
3709-
assert_eq!(path, &*box1);
3710-
assert_eq!(box1, box2);
3711-
assert_eq!(&*box2, path);
3727+
let boxed: Box<Path> = Box::from(path);
3728+
let path_buf = path.to_owned().into_boxed_path().into_path_buf();
3729+
assert_eq!(path, &*boxed);
3730+
assert_eq!(&*boxed, &*path_buf);
3731+
assert_eq!(&*path_buf, path);
37123732
}
37133733

37143734
#[test]

‎src/libstd/sys/redox/os_str.rs

+6
Original file line numberDiff line numberDiff line change
@@ -104,6 +104,12 @@ impl Buf {
104104
pub fn into_box(self) -> Box<Slice> {
105105
unsafe { mem::transmute(self.inner.into_boxed_slice()) }
106106
}
107+
108+
#[inline]
109+
pub fn from_box(boxed: Box<Slice>) -> Buf {
110+
let inner: Box<[u8]> = unsafe { mem::transmute(boxed) };
111+
Buf { inner: inner.into_vec() }
112+
}
107113
}
108114

109115
impl Slice {

‎src/libstd/sys/unix/os_str.rs

+6
Original file line numberDiff line numberDiff line change
@@ -104,6 +104,12 @@ impl Buf {
104104
pub fn into_box(self) -> Box<Slice> {
105105
unsafe { mem::transmute(self.inner.into_boxed_slice()) }
106106
}
107+
108+
#[inline]
109+
pub fn from_box(boxed: Box<Slice>) -> Buf {
110+
let inner: Box<[u8]> = unsafe { mem::transmute(boxed) };
111+
Buf { inner: inner.into_vec() }
112+
}
107113
}
108114

109115
impl Slice {

‎src/libstd/sys/windows/os_str.rs

+6
Original file line numberDiff line numberDiff line change
@@ -97,6 +97,12 @@ impl Buf {
9797
pub fn into_box(self) -> Box<Slice> {
9898
unsafe { mem::transmute(self.inner.into_box()) }
9999
}
100+
101+
#[inline]
102+
pub fn from_box(boxed: Box<Slice>) -> Buf {
103+
let inner: Box<Wtf8> = unsafe { mem::transmute(boxed) };
104+
Buf { inner: Wtf8Buf::from_box(inner) }
105+
}
100106
}
101107

102108
impl Slice {

‎src/libstd/sys_common/wtf8.rs

+6
Original file line numberDiff line numberDiff line change
@@ -351,6 +351,12 @@ impl Wtf8Buf {
351351
pub fn into_box(self) -> Box<Wtf8> {
352352
unsafe { mem::transmute(self.bytes.into_boxed_slice()) }
353353
}
354+
355+
/// Converts a `Box<Wtf8>` into a `Wtf8Buf`.
356+
pub fn from_box(boxed: Box<Wtf8>) -> Wtf8Buf {
357+
let bytes: Box<[u8]> = unsafe { mem::transmute(boxed) };
358+
Wtf8Buf { bytes: bytes.into_vec() }
359+
}
354360
}
355361

356362
/// Create a new WTF-8 string from an iterator of code points.

0 commit comments

Comments
 (0)