Expand on the buffer protocol.

When compiling with --feature nightly, we now use specialization to optimize extract::<Vec<PrimititeType>>() from an object implementing the buffer protocol.
This commit is contained in:
Daniel Grunwald 2017-01-20 23:14:29 +01:00
parent af8131f858
commit 3152ef22f0
4 changed files with 473 additions and 29 deletions

View File

@ -16,33 +16,160 @@
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
use std::{mem, slice};
use std::{mem, slice, cell};
use std::ffi::CStr;
use ffi;
use libc;
use err::{self, PyResult};
use exc;
use python::{Python, PyDrop};
use objects::PyObject;
/// Allows access to the underlying buffer used by a python object such as `bytes`, `bytearray` or `array.array`.
pub struct PyBuffer(Box<ffi::Py_buffer>); // use Box<> because Python expects that the Py_buffer struct has a stable memory address
// PyBuffer is thread-safe: the shape of the buffer is immutable while a Py_buffer exists.
// Accessing the buffer contents is protected using the GIL.
unsafe impl Send for PyBuffer {}
unsafe impl Sync for PyBuffer {}
#[derive(Copy, Clone, Eq, PartialEq)]
pub enum ElementType {
SignedInteger { bytes: usize },
UnsignedInteger { bytes: usize },
Bool,
Float { bytes: usize },
Unknown
}
impl ElementType {
pub fn from_format(format: &CStr) -> ElementType {
let slice = format.to_bytes();
if slice.len() == 1 {
native_element_type_from_type_char(slice[0])
} else if slice.len() == 2 {
match slice[0] {
b'@' => native_element_type_from_type_char(slice[1]),
b'=' | b'<' | b'>' | b'!' => standard_element_type_from_type_char(slice[1]),
_ => ElementType::Unknown
}
} else {
ElementType::Unknown
}
}
}
fn native_element_type_from_type_char(type_char: u8) -> ElementType {
use self::ElementType::*;
match type_char {
b'c' => UnsignedInteger { bytes: mem::size_of::<libc::c_char>() },
b'b' => SignedInteger { bytes: mem::size_of::<libc::c_schar>() },
b'B' => UnsignedInteger { bytes: mem::size_of::<libc::c_uchar>() },
b'?' => Bool,
b'h' => SignedInteger { bytes: mem::size_of::<libc::c_short>() },
b'H' => UnsignedInteger { bytes: mem::size_of::<libc::c_ushort>() },
b'i' => SignedInteger { bytes: mem::size_of::<libc::c_int>() },
b'I' => UnsignedInteger { bytes: mem::size_of::<libc::c_uint>() },
b'l' => SignedInteger { bytes: mem::size_of::<libc::c_long>() },
b'L' => UnsignedInteger { bytes: mem::size_of::<libc::c_ulong>() },
b'q' => SignedInteger { bytes: mem::size_of::<libc::c_longlong>() },
b'Q' => UnsignedInteger { bytes: mem::size_of::<libc::c_ulonglong>() },
b'n' => SignedInteger { bytes: mem::size_of::<libc::ssize_t>() },
b'N' => UnsignedInteger { bytes: mem::size_of::<libc::size_t>() },
b'e' => Float { bytes: 2 },
b'f' => Float { bytes: 4 },
b'd' => Float { bytes: 8 },
_ => Unknown
}
}
fn standard_element_type_from_type_char(type_char: u8) -> ElementType {
use self::ElementType::*;
match type_char {
b'c' => UnsignedInteger { bytes: 1 },
b'b' => SignedInteger { bytes: 1 },
b'B' => UnsignedInteger { bytes: 1 },
b'?' => Bool,
b'h' => SignedInteger { bytes: 2 },
b'H' => UnsignedInteger { bytes: 2 },
b'i' => SignedInteger { bytes: 4 },
b'I' => UnsignedInteger { bytes: 4 },
b'l' => SignedInteger { bytes: 4 },
b'L' => UnsignedInteger { bytes: 4 },
b'q' => SignedInteger { bytes: 8 },
b'Q' => UnsignedInteger { bytes: 8 },
b'e' => Float { bytes: 2 },
b'f' => Float { bytes: 4 },
b'd' => Float { bytes: 8 },
_ => Unknown
}
}
#[cfg(target_endian = "little")]
fn is_matching_endian(c: u8) -> bool {
match c {
b'@' | b'=' | b'<' => true,
_ => false
}
}
#[cfg(target_endian = "big")]
fn is_matching_endian(c: u8) -> bool {
match c {
b'@' | b'=' | b'>' | b'!' => true,
_ => false
}
}
/// Trait implemented for possible element types of `PyBuffer`.
pub unsafe trait Element {
/// Gets whether the element specified in the format string is potentially compatible.
/// Alignment and size are checked separately from this function.
fn is_compatible_format(format: &CStr) -> bool;
}
fn validate(b: &ffi::Py_buffer) {
// shape and stride information must be provided when we use PyBUF_FULL_RO
assert!(!b.shape.is_null());
assert!(!b.strides.is_null());
}
impl PyBuffer {
/// Get the underlying buffer from the specified python object.
pub fn get(py: Python, obj: &PyObject) -> PyResult<PyBuffer> {
unsafe {
let mut buf = Box::new(mem::zeroed::<ffi::Py_buffer>());
err::error_on_minusone(py, ffi::PyObject_GetBuffer(obj.as_ptr(), &mut *buf, ffi::PyBUF_FULL_RO))?;
validate(&buf);
Ok(PyBuffer(buf))
}
}
/// Gets the pointer to the start of the buffer memory.
///
/// Warning: the buffer memory might be mutated by other Python functions,
/// and thus may only be accessed while the GIL is held.
#[inline]
pub fn buf_ptr(&self) -> *mut libc::c_void {
self.0.buf
}
/// Gets a pointer to the specified item.
///
/// If `indices.len() < self.dimensions()`, returns the start address of the sub-array at the specified dimension.
pub fn get_ptr(&self, indices: &[usize]) -> *mut libc::c_void {
let shape = &self.shape()[..indices.len()];
for i in 0..indices.len() {
assert!(indices[i] < shape[i]);
}
unsafe {
ffi::PyBuffer_GetPointer(
&*self.0 as *const ffi::Py_buffer as *mut ffi::Py_buffer,
indices.as_ptr() as *mut usize as *mut ::Py_ssize_t
)
}
}
/// Gets whether the underlying buffer is read-only.
#[inline]
pub fn readonly(&self) -> bool {
@ -86,13 +213,9 @@ impl PyBuffer {
/// Despite Python using an array of signed integers, the values are guaranteed to be non-negative.
/// However, dimensions of length 0 are possible and might need special attention.
#[inline]
pub fn shape(&self) -> Option<&[ffi::Py_ssize_t]> {
pub fn shape(&self) -> &[usize] {
unsafe {
if self.0.shape.is_null() {
None
} else {
Some(slice::from_raw_parts(self.0.shape, self.0.ndim as usize))
}
slice::from_raw_parts(self.0.shape as *const usize, self.0.ndim as usize)
}
}
@ -100,21 +223,20 @@ impl PyBuffer {
///
/// Stride values can be any integer. For regular arrays, strides are usually positive,
/// but a consumer MUST be able to handle the case `strides[n] <= 0`.
///
/// If this function returns `None`, the array is C-contiguous.
#[inline]
pub fn strides(&self) -> Option<&[ffi::Py_ssize_t]> {
pub fn strides(&self) -> &[isize] {
unsafe {
if self.0.strides.is_null() {
None
} else {
Some(slice::from_raw_parts(self.0.strides, self.0.ndim as usize))
}
slice::from_raw_parts(self.0.strides, self.0.ndim as usize)
}
}
/// An array of length ndim.
/// If suboffsets[n] >= 0, the values stored along the nth dimension are pointers and the suboffset value dictates how many bytes to add to each pointer after de-referencing.
/// A suboffset value that is negative indicates that no de-referencing should occur (striding in a contiguous memory block).
///
/// If all suboffsets are negative (i.e. no de-referencing is needed), then this field must be NULL (the default value).
#[inline]
pub fn suboffsets(&self) -> Option<&[ffi::Py_ssize_t]> {
pub fn suboffsets(&self) -> Option<&[isize]> {
unsafe {
if self.0.suboffsets.is_null() {
None
@ -143,7 +265,7 @@ impl PyBuffer {
}
}
/// Gets whether the buffer is contiguous in C-style order (first index varies fastest when visiting items in order of memory address).
/// Gets whether the buffer is contiguous in Fortran-style order (first index varies fastest when visiting items in order of memory address).
#[inline]
pub fn is_fortran_contiguous(&self) -> bool {
unsafe {
@ -151,6 +273,197 @@ impl PyBuffer {
ffi::PyBuffer_IsContiguous(&*self.0 as *const ffi::Py_buffer as *mut ffi::Py_buffer, b'F' as libc::c_char) != 0
}
}
/// Gets the buffer memory as a slice.
///
/// This function succeeds if:
/// * the buffer format is compatible with `T`
/// * alignment and size of buffer elements is matching the expectations for type `T`
/// * the buffer is C-style contiguous
///
/// The returned slice uses type `Cell<T>` because it's theoretically possible for any call into the Python runtime
/// to modify the values in the slice.
pub fn as_slice<'a, T: Element>(&'a self, _py: Python<'a>) -> Option<&'a [ReadOnlyCell<T>]> {
if mem::size_of::<T>() == self.item_size()
&& (self.0.buf as usize) % mem::align_of::<T>() == 0
&& self.is_c_contiguous()
&& T::is_compatible_format(self.format())
{
unsafe { Some(slice::from_raw_parts(self.0.buf as *mut ReadOnlyCell<T>, self.item_count())) }
} else {
None
}
}
/// Gets the buffer memory as a slice.
///
/// This function succeeds if:
/// * the buffer is not read-only
/// * the buffer format is compatible with `T`
/// * alignment and size of buffer elements is matching the expectations for type `T`
/// * the buffer is C-style contiguous
///
/// The returned slice uses type `Cell<T>` because it's theoretically possible for any call into the Python runtime
/// to modify the values in the slice.
pub fn as_mut_slice<'a, T: Element>(&'a self, _py: Python<'a>) -> Option<&'a [cell::Cell<T>]> {
if !self.readonly()
&& mem::size_of::<T>() == self.item_size()
&& (self.0.buf as usize) % mem::align_of::<T>() == 0
&& self.is_c_contiguous()
&& T::is_compatible_format(self.format())
{
unsafe { Some(slice::from_raw_parts(self.0.buf as *mut cell::Cell<T>, self.item_count())) }
} else {
None
}
}
/// Gets the buffer memory as a slice.
///
/// This function succeeds if:
/// * the buffer format is compatible with `T`
/// * alignment and size of buffer elements is matching the expectations for type `T`
/// * the buffer is Fortran-style contiguous
///
/// The returned slice uses type `Cell<T>` because it's theoretically possible for any call into the Python runtime
/// to modify the values in the slice.
pub fn as_fortran_slice<'a, T: Element>(&'a self, _py: Python<'a>) -> Option<&'a [ReadOnlyCell<T>]> {
if mem::size_of::<T>() == self.item_size()
&& (self.0.buf as usize) % mem::align_of::<T>() == 0
&& self.is_fortran_contiguous()
&& T::is_compatible_format(self.format())
{
unsafe { Some(slice::from_raw_parts(self.0.buf as *mut ReadOnlyCell<T>, self.item_count())) }
} else {
None
}
}
/// Gets the buffer memory as a slice.
///
/// This function succeeds if:
/// * the buffer is not read-only
/// * the buffer format is compatible with `T`
/// * alignment and size of buffer elements is matching the expectations for type `T`
/// * the buffer is Fortran-style contiguous
///
/// The returned slice uses type `Cell<T>` because it's theoretically possible for any call into the Python runtime
/// to modify the values in the slice.
pub fn as_fortran_mut_slice<'a, T: Element>(&'a self, _py: Python<'a>) -> Option<&'a [cell::Cell<T>]> {
if !self.readonly()
&& mem::size_of::<T>() == self.item_size()
&& (self.0.buf as usize) % mem::align_of::<T>() == 0
&& self.is_fortran_contiguous()
&& T::is_compatible_format(self.format())
{
unsafe { Some(slice::from_raw_parts(self.0.buf as *mut cell::Cell<T>, self.item_count())) }
} else {
None
}
}
/// Copies the buffer elements to the specified slice.
/// If the buffer is multi-dimensional, the elements are written in C-style order.
///
/// * Fails if the slice does not have the correct length (`buf.item_count()`).
/// * Fails if the buffer format is not compatible with type `T`.
///
/// To check whether the buffer format is compatible before calling this method,
/// you can use `<T as buffer::Element>::is_compatible_format(buf.format())`.
/// Alternatively, `match buffer::ElementType::from_format(buf.format())`.
pub fn copy_to_slice<T: Element+Copy>(&self, py: Python, target: &mut [T]) -> PyResult<()> {
self.copy_to_slice_impl(py, target, b'C')
}
/// Copies the buffer elements to the specified slice.
/// If the buffer is multi-dimensional, the elements are written in Fortran-style order.
///
/// * Fails if the slice does not have the correct length (`buf.item_count()`).
/// * Fails if the buffer format is not compatible with type `T`.
///
/// To check whether the buffer format is compatible before calling this method,
/// you can use `<T as buffer::Element>::is_compatible_format(buf.format())`.
/// Alternatively, `match buffer::ElementType::from_format(buf.format())`.
pub fn copy_to_fortran_slice<T: Element+Copy>(&self, py: Python, target: &mut [T]) -> PyResult<()> {
self.copy_to_slice_impl(py, target, b'F')
}
fn copy_to_slice_impl<T: Element+Copy>(&self, py: Python, target: &mut [T], fort: u8) -> PyResult<()> {
if mem::size_of_val(target) != self.len_bytes() {
return slice_length_error(py);
}
if !T::is_compatible_format(self.format()) || mem::size_of::<T>() != self.item_size() {
return incompatible_format_error(py);
}
unsafe {
err::error_on_minusone(py, ffi::PyBuffer_ToContiguous(
target.as_ptr() as *mut libc::c_void,
&*self.0 as *const ffi::Py_buffer as *mut ffi::Py_buffer,
self.0.len,
fort as libc::c_char
))
}
}
/// Copies the specified slice into the buffer.
/// If the buffer is multi-dimensional, the elements in the slice are expected to be in C-style order.
///
/// * Fails if the buffer is read-only.
/// * Fails if the slice does not have the correct length (`buf.item_count()`).
/// * Fails if the buffer format is not compatible with type `T`.
///
/// To check whether the buffer format is compatible before calling this method,
/// use `<T as buffer::Element>::is_compatible_format(buf.format())`.
/// Alternatively, `match buffer::ElementType::from_format(buf.format())`.
pub fn copy_from_slice<T: Element+Copy>(&self, py: Python, source: &[T]) -> PyResult<()> {
self.copy_from_slice_impl(py, source, b'C')
}
/// Copies the specified slice into the buffer.
/// If the buffer is multi-dimensional, the elements in the slice are expected to be in Fortran-style order.
///
/// * Fails if the buffer is read-only.
/// * Fails if the slice does not have the correct length (`buf.item_count()`).
/// * Fails if the buffer format is not compatible with type `T`.
///
/// To check whether the buffer format is compatible before calling this method,
/// use `<T as buffer::Element>::is_compatible_format(buf.format())`.
/// Alternatively, `match buffer::ElementType::from_format(buf.format())`.
pub fn copy_from_fortran_slice<T: Element+Copy>(&self, py: Python, source: &[T]) -> PyResult<()> {
self.copy_from_slice_impl(py, source, b'F')
}
fn copy_from_slice_impl<T: Element+Copy>(&self, py: Python, source: &[T], fort: u8) -> PyResult<()> {
if self.readonly() {
return buffer_readonly_error(py);
}
if mem::size_of_val(source) != self.len_bytes() {
return slice_length_error(py);
}
if !T::is_compatible_format(self.format()) || mem::size_of::<T>() != self.item_size() {
return incompatible_format_error(py);
}
unsafe {
err::error_on_minusone(py, ffi::PyBuffer_FromContiguous(
&*self.0 as *const ffi::Py_buffer as *mut ffi::Py_buffer,
source.as_ptr() as *mut libc::c_void,
self.0.len,
fort as libc::c_char
))
}
}
}
fn slice_length_error(py: Python) -> PyResult<()> {
Err(err::PyErr::new::<exc::BufferError, _>(py, "Slice length does not match buffer length."))
}
fn incompatible_format_error(py: Python) -> PyResult<()> {
Err(err::PyErr::new::<exc::BufferError, _>(py, "Slice type is incompatible with buffer format."))
}
fn buffer_readonly_error(py: Python) -> PyResult<()> {
Err(err::PyErr::new::<exc::BufferError, _>(py, "Cannot write to read-only buffer."))
}
impl PyDrop for PyBuffer {
@ -167,6 +480,51 @@ impl Drop for PyBuffer {
}
}
/// Like `std::mem::cell`, but only provides read-only access to the data.
///
/// `&ReadOnlyCell<T>` is basically a safe version of `*const T`:
/// The data cannot be modified through the reference, but other references may
/// be modifying the data.
pub struct ReadOnlyCell<T>(cell::UnsafeCell<T>);
impl <T: Copy> ReadOnlyCell<T> {
#[inline]
pub fn get(&self) -> T {
unsafe { *self.0.get() }
}
#[inline]
pub fn as_ptr(&self) -> *const T {
self.0.get()
}
}
macro_rules! impl_element(
($t:ty, $f:ident) => {
unsafe impl Element for $t {
fn is_compatible_format(format: &CStr) -> bool {
let slice = format.to_bytes();
if slice.len() > 1 && !is_matching_endian(slice[0]) {
return false;
}
ElementType::from_format(format) == ElementType::$f { bytes: mem::size_of::<$t>() }
}
}
}
);
impl_element!(u8, UnsignedInteger);
impl_element!(u16, UnsignedInteger);
impl_element!(u32, UnsignedInteger);
impl_element!(u64, UnsignedInteger);
impl_element!(usize, UnsignedInteger);
impl_element!(i8, SignedInteger);
impl_element!(i16, SignedInteger);
impl_element!(i32, SignedInteger);
impl_element!(i64, SignedInteger);
impl_element!(isize, SignedInteger);
impl_element!(f32, Float);
impl_element!(f64, Float);
#[cfg(test)]
mod test {
@ -177,6 +535,12 @@ mod test {
use objectprotocol::ObjectProtocol;
use super::PyBuffer;
#[test]
fn test_compatible_size() {
// for the cast in PyBuffer::shape()
assert_eq!(std::mem::size_of::<::Py_ssize_t>(), std::mem::size_of::<usize>());
}
#[test]
fn test_bytes_buffer() {
let gil = Python::acquire_gil();
@ -186,10 +550,27 @@ mod test {
assert_eq!(buffer.dimensions(), 1);
assert_eq!(buffer.item_count(), 5);
assert_eq!(buffer.format().to_str().unwrap(), "B");
assert_eq!(buffer.shape(), Some::<&[::Py_ssize_t]>(&[5]));
assert_eq!(buffer.shape(), [5]);
// single-dimensional buffer is always contiguous
assert!(buffer.is_c_contiguous());
assert!(buffer.is_fortran_contiguous());
assert!(buffer.as_slice::<f64>(py).is_none());
assert!(buffer.as_slice::<i8>(py).is_none());
let slice = buffer.as_slice::<u8>(py).unwrap();
assert_eq!(slice.len(), 5);
assert_eq!(slice[0].get(), b'a');
assert_eq!(slice[2].get(), b'c');
assert!(buffer.as_mut_slice::<u8>(py).is_none());
assert!(buffer.copy_to_slice(py, &mut [0u8]).is_err());
let mut arr = [0; 5];
buffer.copy_to_slice(py, &mut arr).unwrap();
assert_eq!(arr, [b'a', b'b', b'c', b'd', b'e']);
assert!(buffer.copy_from_slice(py, &[0u8; 5]).is_err());
}
#[test]
@ -202,7 +583,24 @@ mod test {
assert_eq!(buffer.dimensions(), 1);
assert_eq!(buffer.item_count(), 4);
assert_eq!(buffer.format().to_str().unwrap(), "f");
assert_eq!(buffer.shape(), Some::<&[::Py_ssize_t]>(&[4]));
assert_eq!(buffer.shape(), [4]);
assert!(buffer.as_slice::<f64>(py).is_none());
assert!(buffer.as_slice::<i32>(py).is_none());
let slice = buffer.as_slice::<f32>(py).unwrap();
assert_eq!(slice.len(), 4);
assert_eq!(slice[0].get(), 1.0);
assert_eq!(slice[3].get(), 2.5);
let mut_slice = buffer.as_mut_slice::<f32>(py).unwrap();
assert_eq!(mut_slice.len(), 4);
assert_eq!(mut_slice[0].get(), 1.0);
mut_slice[3].set(2.75);
assert_eq!(slice[3].get(), 2.75);
buffer.copy_from_slice(py, &[10.0f32, 11.0, 12.0, 13.0]).unwrap();
assert_eq!(slice[2].get(), 12.0);
}
}

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@ -19,6 +19,7 @@
#![cfg_attr(feature="nightly", feature(
const_fn, // for GILProtected::new (#24111)
shared, // for std::ptr::Shared (#27730)
specialization, // for impl FromPyObject<'source> for Vec<...> (#31844)
))]
#![allow(unused_imports)] // because some imports are only necessary with python 2.x or 3.x
@ -93,7 +94,6 @@ pub use pythonrun::{GILGuard, GILProtected, prepare_freethreaded_python};
pub use conversion::{FromPyObject, RefFromPyObject, ToPyObject};
pub use py_class::{CompareOp};
pub use objectprotocol::{ObjectProtocol};
pub use buffer::PyBuffer;
#[cfg(feature="python27-sys")]
#[allow(non_camel_case_types)]
@ -182,7 +182,7 @@ mod objectprotocol;
mod pythonrun;
pub mod argparse;
mod function;
mod buffer;
pub mod buffer;
//pub mod rustobject;
pub mod py_class;

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@ -101,6 +101,8 @@ exc_type!(ValueError, PyExc_ValueError);
exc_type!(WindowsError, PyExc_WindowsError);
exc_type!(ZeroDivisionError, PyExc_ZeroDivisionError);
exc_type!(BufferError, PyExc_BufferError);
exc_type!(UnicodeDecodeError, PyExc_UnicodeDecodeError);
exc_type!(UnicodeEncodeError, PyExc_UnicodeEncodeError);
exc_type!(UnicodeTranslateError, PyExc_UnicodeTranslateError);

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@ -24,6 +24,7 @@ use objects::{PyObject, PyList, PyTuple, PyIterator};
use ffi::Py_ssize_t;
use err;
use err::{PyErr, PyResult, result_from_owned_ptr, result_cast_from_owned_ptr};
use buffer;
/// Represents a reference to a python object supporting the sequence protocol.
pub struct PySequence(PyObject);
@ -208,10 +209,46 @@ impl PySequence {
}
}
#[cfg(not(feature="nightly"))]
impl <'source, T> FromPyObject<'source> for Vec<T>
where for<'a> T: FromPyObject<'a>
{
fn extract(py: Python, obj: &'source PyObject) -> PyResult<Self> {
extract_sequence(py, obj)
}
}
#[cfg(feature="nightly")]
impl <'source, T> FromPyObject<'source> for Vec<T>
where for<'a> T: FromPyObject<'a>
{
default fn extract(py: Python, obj: &'source PyObject) -> PyResult<Self> {
extract_sequence(py, obj)
}
}
#[cfg(feature="nightly")]
impl <'source, T> FromPyObject<'source> for Vec<T>
where for<'a> T: FromPyObject<'a> + buffer::Element + Default + Copy
{
fn extract(py: Python, obj: &'source PyObject) -> PyResult<Self> {
// first try buffer protocol
if let Ok(buf) = buffer::PyBuffer::get(py, obj) {
if buf.dimensions() == 1 && buf.item_size() == mem::size_of::<T>() && T::is_compatible_format(buf.format()) {
let mut v = vec![T::default(); buf.item_count()];
buf.copy_to_slice(py, &mut v)?;
buf.release_ref(py);
return Ok(v);
}
}
// fall back to sequence protocol
extract_sequence(py, obj)
}
}
fn extract_sequence<T>(py: Python, obj: &PyObject) -> PyResult<Vec<T>>
where for<'a> T: FromPyObject<'a>
{
let seq = try!(obj.cast_as::<PySequence>(py));
let mut v = Vec::new();
for item in try!(seq.iter(py)) {
@ -220,7 +257,6 @@ impl <'source, T> FromPyObject<'source> for Vec<T>
item.release_ref(py);
}
Ok(v)
}
}
#[cfg(test)]
@ -471,4 +507,12 @@ mod test {
let v: Vec<i32> = py.eval("range(1, 5)", None, None).unwrap().extract(py).unwrap();
assert!(v == [1, 2, 3, 4]);
}
#[test]
fn test_extract_bytes_to_vec() {
let gil = Python::acquire_gil();
let py = gil.python();
let v: Vec<u8> = py.eval("b'abc'", None, None).unwrap().extract(py).unwrap();
assert!(v == b"abc");
}
}