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//! This crate defines a buffer data structure optimized to be written to and read from standard
//! `Vec`s. `DataBuffer` is particularly useful when dealing with data whose type is determined at
//! run time. Note that data is stored in the underlying byte buffers in native endian form, thus
//! requesting typed data from a buffer on a platform with different endianness is unsafe.
//!
//! # Caveats
//!
//! `DataBuffer` doesn't support zero-sized types.
pub use reinterpret;
use std::{
any::{Any, TypeId},
mem::size_of,
slice,
};
#[cfg(feature = "numeric")]
use std::fmt;
#[cfg(feature = "numeric")]
use num_traits::{cast, NumCast, Zero};
pub mod macros;
#[cfg(feature = "serde")]
mod serde_helpers {
use std::any::TypeId;
fn transmute_type_id_to_u64(id: &TypeId) -> u64 {
unsafe { std::mem::transmute::<TypeId, u64>(*id) }
}
#[derive(serde::Serialize, serde::Deserialize)]
#[serde(remote = "TypeId")]
pub struct TypeIdDef {
#[serde(getter = "transmute_type_id_to_u64")]
t: u64,
}
impl From<TypeIdDef> for TypeId {
fn from(def: TypeIdDef) -> TypeId {
unsafe { std::mem::transmute::<u64, TypeId>(def.t) }
}
}
}
/// Buffer of plain old data. The data is stored as an array of bytes (`Vec<u8>`).
/// `DataBuffer` keeps track of the type stored within via an explicit `TypeId` member. This allows
/// one to hide the type from the compiler and check it only when necessary. It is particularly
/// useful when the type of data is determined at runtime (e.g. when parsing numeric data).
#[derive(Clone, Debug, PartialEq, Hash)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct DataBuffer {
/// Raw data stored as an array of bytes.
#[cfg_attr(feature = "serde_bytes", serde(with = "serde_bytes"))]
data: Vec<u8>,
/// Number of bytes occupied by ana element of this buffer.
/// Note: We store this instead of length because it gives us the ability to get the type size
/// when the buffer is empty.
element_size: usize,
/// Type encoding for hiding the type of data from the compiler.
#[cfg_attr(feature = "serde", serde(with = "serde_helpers::TypeIdDef"))]
element_type_id: TypeId,
}
impl DataBuffer {
/// Construct an empty `DataBuffer` with a specific type.
#[inline]
pub fn with_type<T: Any>() -> Self {
let element_size = size_of::<T>();
assert_ne!(
element_size, 0,
"DataBuffer doesn't support zero sized types."
);
DataBuffer {
data: Vec::new(),
element_size,
element_type_id: TypeId::of::<T>(),
}
}
/// Construct a `DataBuffer` with the same type as the given buffer without copying its data.
#[inline]
pub fn with_buffer_type(other: &DataBuffer) -> Self {
DataBuffer {
data: Vec::new(),
element_size: other.element_size,
element_type_id: other.element_type_id,
}
}
/// Construct an empty `DataBuffer` with a capacity for a given number of typed elements. For
/// setting byte capacity use `with_byte_capacity`.
#[inline]
pub fn with_capacity<T: Any>(n: usize) -> Self {
let element_size = size_of::<T>();
assert_ne!(
element_size, 0,
"DataBuffer doesn't support zero sized types."
);
DataBuffer {
data: Vec::with_capacity(n * element_size),
element_size,
element_type_id: TypeId::of::<T>(),
}
}
/// Construct a typed `DataBuffer` with a given size and filled with the specified default
/// value.
/// # Examples
/// ```
/// # extern crate data_buffer as buf;
/// # use buf::DataBuffer;
/// # fn main() {
/// let buf = DataBuffer::with_size(8, 42usize); // Create buffer
/// let buf_vec: Vec<usize> = buf.into_vec().unwrap(); // Convert into `Vec`
/// assert_eq!(buf_vec, vec![42usize; 8]);
/// # }
/// ```
#[inline]
pub fn with_size<T: Any + Clone>(n: usize, def: T) -> Self {
Self::from_vec(vec![def; n])
}
/// Construct a `DataBuffer` from a given `Vec<T>` reusing the space already allocated by the
/// given vector.
/// # Examples
/// ```
/// # extern crate data_buffer as buf;
/// # use buf::DataBuffer;
/// # fn main() {
/// let vec = vec![1u8, 3, 4, 1, 2];
/// let buf = DataBuffer::from_vec(vec.clone()); // Convert into buffer
/// let nu_vec: Vec<u8> = buf.into_vec().unwrap(); // Convert back into `Vec`
/// assert_eq!(vec, nu_vec);
/// # }
/// ```
pub fn from_vec<T: Any>(mut vec: Vec<T>) -> Self {
let element_size = size_of::<T>();
assert_ne!(
element_size, 0,
"DataBuffer doesn't support zero sized types."
);
let data = {
let len_in_bytes = vec.len() * element_size;
let capacity_in_bytes = vec.capacity() * element_size;
let vec_ptr = vec.as_mut_ptr() as *mut u8;
unsafe {
::std::mem::forget(vec);
Vec::from_raw_parts(vec_ptr, len_in_bytes, capacity_in_bytes)
}
};
DataBuffer {
data,
element_size,
element_type_id: TypeId::of::<T>(),
}
}
/// Construct a `DataBuffer` from a given slice by cloning the data.
#[inline]
pub fn from_slice<T: Any + Clone>(slice: &[T]) -> Self {
let mut vec = Vec::with_capacity(slice.len());
vec.extend_from_slice(slice);
Self::from_vec(vec)
}
/// Resizes the buffer in-place to store `new_len` elements and returns an optional
/// mutable reference to `Self`.
///
/// If `T` does not correspond to the underlying element type, then `None` is returned and the
/// `DataBuffer` is left unchanged.
///
/// This function has the similar properties to `Vec::resize`.
#[inline]
pub fn resize<T: Any + Clone>(&mut self, new_len: usize, value: T) -> Option<&mut Self> {
self.check_ref::<T>()?;
let size_t = size_of::<T>();
if new_len >= self.len() {
let diff = new_len - self.len();
self.reserve_bytes(diff * size_t);
for _ in 0..diff {
self.push(value.clone());
}
} else {
// Truncate
self.data.resize(new_len * size_t, 0);
}
Some(self)
}
/// Copy data from a given slice into the current buffer.
#[inline]
pub fn copy_from_slice<T: Any + Copy>(&mut self, slice: &[T]) -> &mut Self {
let element_size = size_of::<T>();
assert_ne!(
element_size, 0,
"DataBuffer doesn't support zero sized types."
);
let bins = slice.len() * element_size;
let byte_slice = unsafe { slice::from_raw_parts(slice.as_ptr() as *const u8, bins) };
self.data.resize(bins, 0);
self.data.copy_from_slice(byte_slice);
self.element_size = element_size;
self.element_type_id = TypeId::of::<T>();
self
}
/// Clear the data buffer without destroying its type information.
#[inline]
pub fn clear(&mut self) {
self.data.clear();
}
/// Fill the current buffer with copies of the given value. The size of the buffer is left
/// unchanged. If the given type doesn't patch the internal type, `None` is returned, otherwise
/// a mut reference to the modified buffer is returned.
/// # Examples
/// ```
/// # extern crate data_buffer as buf;
/// # use buf::DataBuffer;
/// # fn main() {
/// let vec = vec![1u8, 3, 4, 1, 2];
/// let mut buf = DataBuffer::from_vec(vec.clone()); // Convert into buffer
/// buf.fill(0u8);
/// assert_eq!(buf.into_vec::<u8>().unwrap(), vec![0u8, 0, 0, 0, 0]);
/// # }
/// ```
#[inline]
pub fn fill<T: Any + Clone>(&mut self, def: T) -> Option<&mut Self> {
for v in self.iter_mut::<T>()? {
*v = def.clone();
}
Some(self)
}
/// Add an element to this buffer. If the type of the given element coincides with the type
/// stored by this buffer, then the modified buffer is returned via a mutable reference.
/// Otherwise, `None` is returned.
#[inline]
pub fn push<T: Any>(&mut self, element: T) -> Option<&mut Self> {
self.check_ref::<T>()?;
let element_ref = &element;
let element_byte_ptr = element_ref as *const T as *const u8;
let element_byte_slice = unsafe { slice::from_raw_parts(element_byte_ptr, size_of::<T>()) };
self.push_bytes(element_byte_slice)
}
/// Check if the current buffer contains elements of the specified type. Returns `Some(self)`
/// if the type matches and `None` otherwise.
#[inline]
pub fn check<T: Any>(self) -> Option<Self> {
if TypeId::of::<T>() != self.element_type_id() {
None
} else {
Some(self)
}
}
/// Check if the current buffer contains elements of the specified type. Returns `None` if the
/// check fails, otherwise a reference to self is returned.
#[inline]
pub fn check_ref<T: Any>(&self) -> Option<&Self> {
if TypeId::of::<T>() != self.element_type_id() {
None
} else {
Some(self)
}
}
/// Check if the current buffer contains elements of the specified type. Same as `check_ref`
/// but consumes and produces a mut reference to self.
#[inline]
pub fn check_mut<'a, T: Any>(&'a mut self) -> Option<&'a mut Self> {
if TypeId::of::<T>() != self.element_type_id() {
None
} else {
Some(self)
}
}
/*
* Accessors
*/
/// Get the `TypeId` of data stored within this buffer.
#[inline]
pub fn element_type_id(&self) -> TypeId {
self.element_type_id
}
/// Get the number of elements stored in this buffer.
#[inline]
pub fn len(&self) -> usize {
debug_assert_eq!(self.data.len() % self.element_size, 0);
self.data.len() / self.element_size // element_size is guaranteed to be strictly positive
}
/// Check if there are any elements stored in this buffer.
#[inline]
pub fn is_empty(&self) -> bool {
self.data.is_empty()
}
/// Get the byte capacity of this buffer.
#[inline]
pub fn byte_capacity(&self) -> usize {
self.data.capacity()
}
/// Get the size of the element type.
#[inline]
pub fn element_size(&self) -> usize {
self.element_size
}
/// Return an iterator to a slice representing typed data.
/// Returs `None` if the given type `T` doesn't match the internal.
/// # Examples
/// ```
/// # extern crate data_buffer as buf;
/// # use buf::DataBuffer;
/// # fn main() {
/// let vec = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
/// let buf = DataBuffer::from(vec.clone()); // Convert into buffer
/// for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
/// assert_eq!(val, vec[i]);
/// }
/// # }
/// ```
#[inline]
pub fn iter<'a, T: Any + 'a>(&'a self) -> Option<slice::Iter<T>> {
self.as_slice::<T>().map(|x| x.iter())
}
/// Return an iterator to a mutable slice representing typed data.
/// Returs `None` if the given type `T` doesn't match the internal.
#[inline]
pub fn iter_mut<'a, T: Any + 'a>(&'a mut self) -> Option<slice::IterMut<T>> {
self.as_mut_slice::<T>().map(|x| x.iter_mut())
}
/// Append cloned items from this buffer to a given `Vec<T>`. Return the mutable reference
/// `Some(vec)` if type matched the internal type and `None` otherwise.
#[inline]
pub fn append_clone_to_vec<'a, T>(&self, vec: &'a mut Vec<T>) -> Option<&'a mut Vec<T>>
where
T: Any + Clone,
{
vec.extend_from_slice(self.as_slice()?);
Some(vec)
}
/// Append copied items from this buffer to a given `Vec<T>`. Return the mutable reference
/// `Some(vec)` if type matched the internal type and `None` otherwise. This may be faster than
/// `append_clone_to_vec`.
#[inline]
pub fn append_copy_to_vec<'a, T>(&self, vec: &'a mut Vec<T>) -> Option<&'a mut Vec<T>>
where
T: Any + Copy,
{
vec.extend(self.iter()?);
Some(vec)
}
/// Clones contents of `self` into the given `Vec`.
#[inline]
pub fn clone_into_vec<T: Any + Clone>(&self) -> Option<Vec<T>> {
let mut vec = Vec::<T>::with_capacity(self.len());
match self.append_clone_to_vec(&mut vec) {
Some(_) => Some(vec),
None => None,
}
}
/// Copies contents of `self` into the given `Vec`.
#[inline]
pub fn copy_into_vec<T: Any + Copy>(&self) -> Option<Vec<T>> {
let mut vec = Vec::<T>::with_capacity(self.len());
match self.append_copy_to_vec(&mut vec) {
Some(_) => Some(vec),
None => None,
}
}
/// An alternative to using the `Into` trait. This function helps the compiler
/// determine the type `T` automatically.
#[inline]
pub fn into_vec<T: Any>(self) -> Option<Vec<T>> {
unsafe { self.check::<T>().map(|x| x.reinterpret_into_vec()) }
}
/// Convert this buffer into a typed slice.
/// Returs `None` if the given type `T` doesn't match the internal.
#[inline]
pub fn as_slice<T: Any>(&self) -> Option<&[T]> {
let ptr = self.check_ref::<T>()?.data.as_ptr() as *const T;
Some(unsafe { slice::from_raw_parts(ptr, self.len()) })
}
/// Convert this buffer into a typed mutable slice.
/// Returs `None` if the given type `T` doesn't match the internal.
#[inline]
pub fn as_mut_slice<T: Any>(&mut self) -> Option<&mut [T]> {
let ptr = self.check_mut::<T>()?.data.as_mut_ptr() as *mut T;
Some(unsafe { slice::from_raw_parts_mut(ptr, self.len()) })
}
/// Get `i`'th element of the buffer by value.
#[inline]
pub fn get<T: Any + Copy>(&self, i: usize) -> Option<T> {
assert!(i < self.len());
let ptr = self.check_ref::<T>()?.data.as_ptr() as *const T;
Some(unsafe { *ptr.add(i) })
}
/// Get a `const` reference to the `i`'th element of the buffer.
#[inline]
pub fn get_ref<T: Any>(&self, i: usize) -> Option<&T> {
assert!(i < self.len());
let ptr = self.check_ref::<T>()?.data.as_ptr() as *const T;
Some(unsafe { &*ptr.add(i) })
}
/// Get a mutable reference to the `i`'th element of the buffer.
#[inline]
pub fn get_mut<T: Any>(&mut self, i: usize) -> Option<&mut T> {
assert!(i < self.len());
let ptr = self.check_mut::<T>()?.data.as_mut_ptr() as *mut T;
Some(unsafe { &mut *ptr.add(i) })
}
/*
* Advanced methods to probe buffer internals.
*/
/// Reserves capacity for at least `additional` more bytes to be inserted in this buffer.
#[inline]
pub fn reserve_bytes(&mut self, additional: usize) {
self.data.reserve(additional);
}
/// Get `i`'th element of the buffer by value without checking type.
/// This can be used to reinterpret the internal data as a different type. Note that if the
/// size of the given type `T` doesn't match the size of the internal type, `i` will really
/// index the `i`th `T` sized chunk in the current buffer. See the implementation for details.
#[inline]
pub unsafe fn get_unchecked<T: Any + Copy>(&self, i: usize) -> T {
let ptr = self.data.as_ptr() as *const T;
*ptr.add(i)
}
/// Get a `const` reference to the `i`'th element of the buffer.
/// This can be used to reinterpret the internal data as a different type. Note that if the
/// size of the given type `T` doesn't match the size of the internal type, `i` will really
/// index the `i`th `T` sized chunk in the current buffer. See the implementation for details.
#[inline]
pub unsafe fn get_unchecked_ref<T: Any>(&self, i: usize) -> &T {
let ptr = self.data.as_ptr() as *const T;
&*ptr.add(i)
}
/// Get a mutable reference to the `i`'th element of the buffer.
/// This can be used to reinterpret the internal data as a different type. Note that if the
/// size of the given type `T` doesn't match the size of the internal type, `i` will really
/// index the `i`th `T` sized chunk in the current buffer. See the implementation for details.
#[inline]
pub unsafe fn get_unchecked_mut<T: Any>(&mut self, i: usize) -> &mut T {
let ptr = self.data.as_mut_ptr() as *mut T;
&mut *ptr.add(i)
}
/// Get a `const` reference to the byte slice of the `i`'th element of the buffer.
#[inline]
pub fn get_bytes(&self, i: usize) -> &[u8] {
assert!(i < self.len());
let element_size = self.element_size();
&self.data[i * element_size..(i + 1) * element_size]
}
/// Get a mutable reference to the byte slice of the `i`'th element of the buffer.
#[inline]
pub fn get_bytes_mut(&mut self, i: usize) -> &mut [u8] {
assert!(i < self.len());
let element_size = self.element_size();
&mut self.data[i * element_size..(i + 1) * element_size]
}
/// Move buffer data to a vector with a given type, reinterpreting the data type as
/// required.
#[inline]
pub unsafe fn reinterpret_into_vec<T>(self) -> Vec<T> {
reinterpret::reinterpret_vec(self.data)
}
/// Borrow buffer data and reinterpret it as a slice of a given type.
#[inline]
pub unsafe fn reinterpret_as_slice<T>(&self) -> &[T] {
reinterpret::reinterpret_slice(self.data.as_slice())
}
/// Mutably borrow buffer data and reinterpret it as a mutable slice of a given type.
#[inline]
pub unsafe fn reinterpret_as_mut_slice<T>(&mut self) -> &mut [T] {
reinterpret::reinterpret_mut_slice(self.data.as_mut_slice())
}
/// Borrow buffer data and iterate over reinterpreted underlying data.
#[inline]
pub unsafe fn reinterpret_iter<T>(&self) -> slice::Iter<T> {
self.reinterpret_as_slice().iter()
}
/// Mutably borrow buffer data and mutably iterate over reinterpreted underlying data.
#[inline]
pub unsafe fn reinterpret_iter_mut<T>(&mut self) -> slice::IterMut<T> {
self.reinterpret_as_mut_slice().iter_mut()
}
/// Peak at the internal representation of the data.
#[inline]
pub fn as_bytes(&self) -> &[u8] {
self.data.as_slice()
}
/// Get a mutable reference to the internal data representation.
#[inline]
pub fn as_bytes_mut(&mut self) -> &mut [u8] {
self.data.as_mut_slice()
}
/// Iterate over chunks type sized chunks of bytes without interpreting them. This avoids
/// needing to know what type data you're dealing with. This type of iterator is useful for
/// transferring data from one place to another for a generic buffer.
#[inline]
pub fn byte_chunks<'a>(&'a self) -> impl Iterator<Item = &'a [u8]> + 'a {
let chunk_size = self.element_size();
self.data.chunks(chunk_size)
}
/// Mutably iterate over chunks type sized chunks of bytes without interpreting them. This
/// avoids needing to know what type data you're dealing with. This type of iterator is useful
/// for transferring data from one place to another for a generic buffer, or modifying the
/// underlying untyped bytes (e.g. bit twiddling).
#[inline]
pub fn byte_chunks_mut<'a>(&'a mut self) -> impl Iterator<Item = &'a mut [u8]> + 'a {
let chunk_size = self.element_size();
self.data.chunks_mut(chunk_size)
}
/// Add bytes to this buffer. If the size of the given slice coincides with the number of bytes
/// occupied by the underlying element type, then these bytes are added to the underlying data
/// buffer and a mutable reference to the buffer is returned.
/// Otherwise, `None` is returned, and the buffer remains unmodified.
#[inline]
pub fn push_bytes(&mut self, bytes: &[u8]) -> Option<&mut Self> {
if bytes.len() == self.element_size() {
self.data.extend_from_slice(bytes);
Some(self)
} else {
None
}
}
/// Add bytes to this buffer. If the size of the given slice is a multiple of the number of bytes
/// occupied by the underlying element type, then these bytes are added to the underlying data
/// buffer and a mutable reference to the buffer is returned.
/// Otherwise, `None` is returned and the buffer is unmodified.
#[inline]
pub fn extend_bytes(&mut self, bytes: &[u8]) -> Option<&mut Self> {
let element_size = self.element_size();
if bytes.len() % element_size == 0 {
self.data.extend_from_slice(bytes);
Some(self)
} else {
None
}
}
/// Move bytes to this buffer. If the size of the given vector is a multiple of the number of bytes
/// occupied by the underlying element type, then these bytes are moved to the underlying data
/// buffer and a mutable reference to the buffer is returned.
/// Otherwise, `None` is returned and both the buffer and the input vector remain unmodified.
#[inline]
pub fn append_bytes(&mut self, bytes: &mut Vec<u8>) -> Option<&mut Self> {
let element_size = self.element_size();
if bytes.len() % element_size == 0 {
self.data.append(bytes);
Some(self)
} else {
None
}
}
/// Move bytes to this buffer. The given buffer must have the same underlying type as self.
#[inline]
pub fn append(&mut self, buf: &mut DataBuffer) -> Option<&mut Self> {
if buf.element_type_id() == self.element_type_id() {
self.data.append(&mut buf.data);
Some(self)
} else {
None
}
}
/// Rotates the slice in-place such that the first `mid` elements of the slice move to the end
/// while the last `self.len() - mid` elements move to the front. After calling `rotate_left`,
/// the element previously at index `mid` will become the first element in the slice.
///
/// # Example
///
/// ```
/// # use data_buffer::*;
/// let mut buf = DataBuffer::from_vec(vec![1u32,2,3,4,5]);
/// buf.rotate_left(3);
/// assert_eq!(buf.as_slice::<u32>().unwrap(), &[4,5,1,2,3]);
/// ```
#[inline]
pub fn rotate_left(&mut self, mid: usize) {
self.data.rotate_left(mid * self.element_size);
}
/// Rotates the slice in-place such that the first `self.len() - k` elements of the slice move
/// to the end while the last `k` elements move to the front. After calling `rotate_right`, the
/// element previously at index `k` will become the first element in the slice.
///
/// # Example
///
/// ```
/// # use data_buffer::*;
/// let mut buf = DataBuffer::from_vec(vec![1u32,2,3,4,5]);
/// buf.rotate_right(3);
/// assert_eq!(buf.as_slice::<u32>().unwrap(), &[3,4,5,1,2]);
/// ```
#[inline]
pub fn rotate_right(&mut self, k: usize) {
self.data.rotate_right(k * self.element_size);
}
/*
* Methods specific to buffers storing numeric data
*/
#[cfg(feature = "numeric")]
/// Cast a numeric `DataBuffer` into the given output `Vec` type.
pub fn cast_into_vec<T>(self) -> Vec<T>
where
T: Any + Copy + NumCast + Zero,
{
// Helper function (generic on the input) to convert the given DataBuffer into Vec.
unsafe fn convert_into_vec<I, O>(buf: DataBuffer) -> Vec<O>
where
I: Any + NumCast,
O: Any + Copy + NumCast + Zero,
{
debug_assert_eq!(buf.element_type_id(), TypeId::of::<I>()); // Check invariant.
buf.reinterpret_into_vec()
.into_iter()
.map(|elem: I| cast(elem).unwrap_or(O::zero()))
.collect()
}
call_numeric_buffer_fn!( convert_into_vec::<_,T>(self) or { Vec::new() } )
}
#[cfg(feature = "numeric")]
/// Display the contents of this buffer reinterpreted in the given type.
unsafe fn reinterpret_display<T: Any + fmt::Display>(&self, f: &mut fmt::Formatter) {
debug_assert_eq!(self.element_type_id(), TypeId::of::<T>()); // Check invariant.
for item in self.reinterpret_iter::<T>() {
write!(f, "{} ", item).expect("Error occurred while writing an DataBuffer.");
}
}
}
/// Convert a `Vec<T>` to a `DataBuffer`.
impl<T> From<Vec<T>> for DataBuffer
where
T: Any,
{
#[inline]
fn from(vec: Vec<T>) -> DataBuffer {
DataBuffer::from_vec(vec)
}
}
/// Convert a `&[T]` to a `DataBuffer`.
impl<'a, T> From<&'a [T]> for DataBuffer
where
T: Any + Clone,
{
#[inline]
fn from(slice: &'a [T]) -> DataBuffer {
DataBuffer::from_slice(slice)
}
}
/// Convert a `DataBuffer` to a `Option<Vec<T>>`.
impl<T> Into<Option<Vec<T>>> for DataBuffer
where
T: Any + Clone,
{
#[inline]
fn into(self) -> Option<Vec<T>> {
self.into_vec()
}
}
#[cfg(feature = "numeric")]
/// Implement pretty printing of numeric `DataBuffer` data.
impl fmt::Display for DataBuffer {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
call_numeric_buffer_fn!( self.reinterpret_display::<_>(f) or {
println!("Unknown DataBuffer type for pretty printing.");
} );
write!(f, "")
}
}
#[cfg(test)]
mod tests {
use super::*;
/// Test various ways to create a data buffer.
#[test]
fn initialization_test() {
// Empty typed buffer.
let a = DataBuffer::with_type::<f32>();
assert_eq!(a.len(), 0);
assert_eq!(a.as_bytes().len(), 0);
assert_eq!(a.element_type_id(), TypeId::of::<f32>());
assert_eq!(a.byte_capacity(), 0); // Ensure nothing is allocated.
// Empty buffer typed by the given type id.
let b = DataBuffer::with_buffer_type(&a);
assert_eq!(b.len(), 0);
assert_eq!(b.as_bytes().len(), 0);
assert_eq!(b.element_type_id(), TypeId::of::<f32>());
assert_eq!(a.byte_capacity(), 0); // Ensure nothing is allocated.
// Empty typed buffer with a given capacity.
let a = DataBuffer::with_capacity::<f32>(4);
assert_eq!(a.len(), 0);
assert_eq!(a.as_bytes().len(), 0);
assert_eq!(a.byte_capacity(), 4 * size_of::<f32>());
assert_eq!(a.element_type_id(), TypeId::of::<f32>());
}
/// Test reserving capacity after creation.
#[test]
fn reserve_bytes() {
let mut a = DataBuffer::with_type::<f32>();
assert_eq!(a.byte_capacity(), 0);
a.reserve_bytes(10);
assert_eq!(a.len(), 0);
assert_eq!(a.as_bytes().len(), 0);
assert!(a.byte_capacity() >= 10);
}
/// Test resizing a buffer.
#[test]
fn resize() {
let mut a = DataBuffer::with_type::<f32>();
// Increase the size of a.
a.resize(3, 1.0f32);
assert_eq!(a.len(), 3);
assert_eq!(a.as_bytes().len(), 12);
for i in 0..3 {
assert_eq!(a.get::<f32>(i).unwrap(), 1.0f32);
}
// Truncate a.
a.resize(2, 1.0f32);
assert_eq!(a.len(), 2);
assert_eq!(a.as_bytes().len(), 8);
for i in 0..2 {
assert_eq!(a.get::<f32>(i).unwrap(), 1.0f32);
}
}
#[test]
#[should_panic]
fn zero_size_with_type_test() {
let _a = DataBuffer::with_type::<()>();
}
#[test]
#[should_panic]
fn zero_size_with_capacity_test() {
let _a = DataBuffer::with_capacity::<()>(2);
}
#[test]
#[should_panic]
fn zero_size_from_vec_test() {
let _a = DataBuffer::from_vec(vec![(); 3]);
}
#[test]
#[should_panic]
fn zero_size_with_size_test() {
let _a = DataBuffer::with_size(3, ());
}
#[test]
#[should_panic]
fn zero_size_from_slice_test() {
let v = vec![(); 3];
let _a = DataBuffer::from_slice(&v);
}
#[test]
#[should_panic]
fn zero_size_copy_from_slice_test() {
let v = vec![(); 3];
let mut a = DataBuffer::with_size(0, 1i32);
a.copy_from_slice(&v);
}
#[test]
fn data_integrity_u8_test() {
let vec = vec![1u8, 3, 4, 1, 2];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<u8> = buf.copy_into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
let vec = vec![1u8, 3, 4, 1, 2, 52, 1, 3, 41, 23, 2];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<u8> = buf.copy_into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[test]
fn data_integrity_i16_test() {
let vec = vec![1i16, -3, 1002, -231, 32];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<i16> = buf.copy_into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
let vec = vec![1i16, -3, 1002, -231, 32, 42, -123, 4];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<i16> = buf.copy_into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[test]
fn data_integrity_i32_test() {
let vec = vec![1i32, -3, 1002, -231, 32];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<i32> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
let vec = vec![1i32, -3, 1002, -231, 32, 42, -123];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<i32> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[test]
fn data_integrity_f32_test() {
let vec = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<f32> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
let vec = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43, 2e-1];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<f32> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[test]
fn data_integrity_f64_test() {
let vec = vec![1f64, -3.0, 10.02, -23.1, 32e-1];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<f64> = buf.copy_into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
let vec = vec![1f64, -3.1, 100.2, -2.31, 3.2, 4e2, -1e23];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<f64> = buf.copy_into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[cfg(feature = "numeric")]
#[test]
fn convert_float_test() {
let vecf64 = vec![1f64, -3.0, 10.02, -23.1, 32e-1];
let buf = DataBuffer::from(vecf64.clone()); // Convert into buffer
let nu_vec: Vec<f32> = buf.cast_into_vec(); // Convert back into vec
let vecf32 = vec![1f32, -3.0, 10.02, -23.1, 32e-1];
assert_eq!(vecf32, nu_vec);
let buf = DataBuffer::from(vecf32.clone()); // Convert into buffer
let nu_vec: Vec<f64> = buf.cast_into_vec(); // Convert back into vec
for (&a, &b) in vecf64.iter().zip(nu_vec.iter()) {
assert!((a - b).abs() < 1e-6f64 * f64::max(a, b).abs());
}
let vecf64 = vec![1f64, -3.1, 100.2, -2.31, 3.2, 4e2, -1e23];
let buf = DataBuffer::from(vecf64.clone()); // Convert into buffer
let nu_vec: Vec<f32> = buf.cast_into_vec(); // Convert back into vec
let vecf32 = vec![1f32, -3.1, 100.2, -2.31, 3.2, 4e2, -1e23];
assert_eq!(vecf32, nu_vec);
let buf = DataBuffer::from(vecf32.clone()); // Convert into buffer
let nu_vec: Vec<f64> = buf.cast_into_vec(); // Convert back into vec
for (&a, &b) in vecf64.iter().zip(nu_vec.iter()) {
assert!((a - b).abs() < 1e-6 * f64::max(a, b).abs());
}
}
#[derive(Clone, Debug, PartialEq)]
struct Foo {
a: u8,
b: i64,
c: f32,
}
#[test]
fn from_empty_vec_test() {
let vec: Vec<u32> = Vec::new();
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<u32> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
let vec: Vec<String> = Vec::new();
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<String> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
let vec: Vec<Foo> = Vec::new();
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<Foo> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[test]
fn from_struct_test() {
let f1 = Foo {
a: 3,
b: -32,
c: 54.2,
};
let f2 = Foo {
a: 33,
b: -3342432412,
c: 323454.2,
};
let vec = vec![f1.clone(), f2.clone()];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
assert_eq!(f1, buf.get_ref::<Foo>(0).unwrap().clone());
assert_eq!(f2, buf.get_ref::<Foo>(1).unwrap().clone());
let nu_vec: Vec<Foo> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[test]
fn from_strings_test() {
let vec = vec![
String::from("hi"),
String::from("hello"),
String::from("goodbye"),
String::from("bye"),
String::from("supercalifragilisticexpialidocious"),
String::from("42"),
];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
assert_eq!("hi", buf.get_ref::<String>(0).unwrap());
assert_eq!("hello", buf.get_ref::<String>(1).unwrap());
assert_eq!("goodbye", buf.get_ref::<String>(2).unwrap());
let nu_vec: Vec<String> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
#[test]
fn iter_test() {
// Check iterating over data with a larger size than 8 bits.
let vec_f32 = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
let buf = DataBuffer::from(vec_f32.clone()); // Convert into buffer
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
// Check iterating over data with the same size.
let vec_u8 = vec![1u8, 3, 4, 1, 2, 4, 128, 32];
let buf = DataBuffer::from(vec_u8.clone()); // Convert into buffer
for (i, &val) in buf.iter::<u8>().unwrap().enumerate() {
assert_eq!(val, vec_u8[i]);
}
// Check unsafe functions:
unsafe {
// TODO: feature gate these two tests for little endian platforms.
// Check iterating over data with a larger size than input.
let vec_u32 = vec![17_040_129u32, 545_260_546]; // little endian
let buf = DataBuffer::from(vec_u8.clone()); // Convert into buffer
for (i, &val) in buf.reinterpret_iter::<u32>().enumerate() {
assert_eq!(val, vec_u32[i]);
}
// Check iterating over data with a smaller size than input
let mut buf2 = DataBuffer::from(vec_u32); // Convert into buffer
for (i, &val) in buf2.reinterpret_iter::<u8>().enumerate() {
assert_eq!(val, vec_u8[i]);
}
// Check mut iterator
buf2.reinterpret_iter_mut::<u8>().for_each(|val| *val += 1);
let u8_check_vec = vec![2u8, 4, 5, 2, 3, 5, 129, 33];
assert_eq!(buf2.reinterpret_into_vec::<u8>(), u8_check_vec);
}
}
#[test]
fn large_sizes_test() {
for i in 1000000..1000010 {
let vec = vec![32u8; i];
let buf = DataBuffer::from(vec.clone()); // Convert into buffer
let nu_vec: Vec<u8> = buf.into_vec().unwrap(); // Convert back into vec
assert_eq!(vec, nu_vec);
}
}
/// This test checks that an error is returned whenever the user tries to access data with the
/// wrong type data.
#[test]
fn wrong_type_test() {
let vec = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
let mut buf = DataBuffer::from(vec.clone()); // Convert into buffer
assert_eq!(vec, buf.clone_into_vec::<f32>().unwrap());
assert!(buf.copy_into_vec::<f64>().is_none());
assert!(buf.as_slice::<f64>().is_none());
assert!(buf.as_mut_slice::<u8>().is_none());
assert!(buf.iter::<[f32; 3]>().is_none());
assert!(buf.get::<i32>(0).is_none());
assert!(buf.get_ref::<i32>(1).is_none());
assert!(buf.get_mut::<i32>(2).is_none());
}
/// Test iterating over chunks of data without having to interpret them.
#[test]
fn byte_chunks_test() {
let vec_f32 = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
let buf = DataBuffer::from(vec_f32.clone()); // Convert into buffer
for (i, val) in buf.byte_chunks().enumerate() {
assert_eq!(
unsafe { reinterpret::reinterpret_slice::<u8, f32>(val)[0] },
vec_f32[i]
);
}
}
/// Test pushing values and bytes to a buffer.
#[test]
fn push_test() {
let mut vec_f32 = vec![1.0_f32, 23.0, 0.01];
let mut buf = DataBuffer::from(vec_f32.clone()); // Convert into buffer
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
vec_f32.push(42.0f32);
buf.push(42.0f32).unwrap(); // must provide explicit type
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
vec_f32.push(11.43);
buf.push(11.43f32).unwrap();
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
// Zero float is always represented by four zero bytes in IEEE format.
vec_f32.push(0.0);
vec_f32.push(0.0);
buf.extend_bytes(&[0, 0, 0, 0, 0, 0, 0, 0]).unwrap();
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
// Test byte getters
for i in 5..7 {
assert_eq!(buf.get_bytes(i), &[0, 0, 0, 0]);
assert_eq!(buf.get_bytes_mut(i), &[0, 0, 0, 0]);
}
vec_f32.push(0.0);
buf.push_bytes(&[0, 0, 0, 0]).unwrap();
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
}
/// Test appending to a data buffer from another data buffer.
#[test]
fn append_test() {
let mut buf = DataBuffer::with_type::<f32>(); // Create an empty buffer.
let data = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
// Append an ordianry vector of data.
let mut other_buf = DataBuffer::from_vec(data.clone());
buf.append(&mut other_buf);
assert!(other_buf.is_empty());
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, data[i]);
}
}
/// Test appending to a data buffer from other slices and vectors.
#[test]
fn extend_append_bytes_test() {
let mut buf = DataBuffer::with_type::<f32>(); // Create an empty buffer.
// Append an ordianry vector of data.
let vec_f32 = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
let mut vec_bytes: Vec<u8> = unsafe { reinterpret::reinterpret_vec(vec_f32.clone()) };
buf.append_bytes(&mut vec_bytes);
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
buf.clear();
assert_eq!(buf.len(), 0);
// Append a temporary vec.
buf.append_bytes(&mut vec![0u8; 4]);
assert_eq!(buf.get::<f32>(0).unwrap(), 0.0f32);
buf.clear();
assert_eq!(buf.len(), 0);
// Extend buffer with a slice
let slice_bytes: &[u8] = unsafe { reinterpret::reinterpret_slice(&vec_f32) };
buf.extend_bytes(slice_bytes);
for (i, &val) in buf.iter::<f32>().unwrap().enumerate() {
assert_eq!(val, vec_f32[i]);
}
}
#[cfg(feature = "serde")]
#[test]
fn serde_test() {
let vec_f32 = vec![1.0_f32, 23.0, 0.01, 42.0, 11.43];
let buf = DataBuffer::from(vec_f32.clone()); // Convert into buffer
dbg!(&buf);
let buf_str = serde_json::to_string(&buf).expect("Failed to serialize DataBuffer.");
dbg!(&buf_str);
let new_buf = serde_json::from_str(&buf_str).expect("Failed to deserialize DataBuffer.");
dbg!(&new_buf);
assert_eq!(buf, new_buf);
}
}