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use crate::{
ffi, AsPyPointer, FromPyObject, IntoPy, Py, PyAny, PyObject, PyResult, PyTryFrom, Python,
ToPyObject,
};
use std::ops::Index;
use std::os::raw::c_char;
use std::slice::SliceIndex;
use std::str;
#[repr(transparent)]
pub struct PyBytes(PyAny);
pyobject_native_var_type!(PyBytes, ffi::PyBytes_Type, ffi::PyBytes_Check);
impl PyBytes {
pub fn new<'p>(py: Python<'p>, s: &[u8]) -> &'p PyBytes {
let ptr = s.as_ptr() as *const c_char;
let len = s.len() as ffi::Py_ssize_t;
unsafe { py.from_owned_ptr(ffi::PyBytes_FromStringAndSize(ptr, len)) }
}
pub fn new_with<F>(py: Python, len: usize, init: F) -> PyResult<&PyBytes>
where
F: FnOnce(&mut [u8]) -> PyResult<()>,
{
unsafe {
let pyptr = ffi::PyBytes_FromStringAndSize(std::ptr::null(), len as ffi::Py_ssize_t);
let pypybytes: Py<PyBytes> = Py::from_owned_ptr_or_err(py, pyptr)?;
let buffer = ffi::PyBytes_AsString(pyptr) as *mut u8;
debug_assert!(!buffer.is_null());
std::ptr::write_bytes(buffer, 0u8, len);
init(std::slice::from_raw_parts_mut(buffer, len)).map(|_| pypybytes.into_ref(py))
}
}
pub unsafe fn from_ptr(py: Python<'_>, ptr: *const u8, len: usize) -> &PyBytes {
py.from_owned_ptr(ffi::PyBytes_FromStringAndSize(
ptr as *const _,
len as isize,
))
}
#[inline]
pub fn as_bytes(&self) -> &[u8] {
unsafe {
let buffer = ffi::PyBytes_AsString(self.as_ptr()) as *const u8;
let length = ffi::PyBytes_Size(self.as_ptr()) as usize;
debug_assert!(!buffer.is_null());
std::slice::from_raw_parts(buffer, length)
}
}
}
impl<I: SliceIndex<[u8]>> Index<I> for PyBytes {
type Output = I::Output;
fn index(&self, index: I) -> &Self::Output {
&self.as_bytes()[index]
}
}
impl<'a> IntoPy<PyObject> for &'a [u8] {
fn into_py(self, py: Python) -> PyObject {
PyBytes::new(py, self).to_object(py)
}
}
impl<'a> FromPyObject<'a> for &'a [u8] {
fn extract(obj: &'a PyAny) -> PyResult<Self> {
Ok(<PyBytes as PyTryFrom>::try_from(obj)?.as_bytes())
}
}
#[cfg(test)]
mod test {
use super::PyBytes;
use crate::FromPyObject;
use crate::Python;
#[test]
fn test_extract_bytes() {
let gil = Python::acquire_gil();
let py = gil.python();
let py_bytes = py.eval("b'Hello Python'", None, None).unwrap();
let bytes: &[u8] = FromPyObject::extract(py_bytes).unwrap();
assert_eq!(bytes, b"Hello Python");
}
#[test]
fn test_bytes_index() {
let gil = Python::acquire_gil();
let py = gil.python();
let bytes = PyBytes::new(py, b"Hello World");
assert_eq!(bytes[1], b'e');
}
#[test]
fn test_bytes_new_with() -> super::PyResult<()> {
let gil = Python::acquire_gil();
let py = gil.python();
let py_bytes = PyBytes::new_with(py, 10, |b: &mut [u8]| {
b.copy_from_slice(b"Hello Rust");
Ok(())
})?;
let bytes: &[u8] = FromPyObject::extract(py_bytes)?;
assert_eq!(bytes, b"Hello Rust");
Ok(())
}
#[test]
fn test_bytes_new_with_zero_initialised() -> super::PyResult<()> {
let gil = Python::acquire_gil();
let py = gil.python();
let py_bytes = PyBytes::new_with(py, 10, |_b: &mut [u8]| Ok(()))?;
let bytes: &[u8] = FromPyObject::extract(py_bytes)?;
assert_eq!(bytes, &[0; 10]);
Ok(())
}
#[test]
fn test_bytes_new_with_error() {
use crate::exceptions::PyValueError;
let gil = Python::acquire_gil();
let py = gil.python();
let py_bytes_result = PyBytes::new_with(py, 10, |_b: &mut [u8]| {
Err(PyValueError::new_err("Hello Crustaceans!"))
});
assert!(py_bytes_result.is_err());
assert!(py_bytes_result
.err()
.unwrap()
.is_instance::<PyValueError>(py));
}
}