Struct Null 

pub struct Null { /* private fields */ }

Available on crate features test-util only.

A Read and Write that does nothing.

Any data written to it is discarded and it never returns any data when read from. Intended for simple tests and examples only.

Implementations

impl Null

pub fn builder() -> NullBuilder

Starts building a new NullStream.

pub fn new() -> Self

Creates a new NullStream with the default configuration.

pub async fn read_at_most_into( &mut self, _len: usize, into: BytesBuf, ) -> Result<(usize, BytesBuf), Infallible>

Reads 0 bytes into the provided buffer, returning it as-is.

Errors

This call never fails.

pub async fn read_more_into( &mut self, into: BytesBuf, ) -> Result<(usize, BytesBuf), Infallible>

Reads 0 bytes into the provided buffer, returning it as-is.

Errors

This call never fails.

pub async fn read_any(&mut self) -> Result<BytesBuf, Infallible>

Reads 0 bytes.

Errors

This call never fails.

pub async fn write(&mut self, _sequence: BytesView) -> Result<(), Infallible>

“Writes” the provided data, discarding it.

Errors

This call never fails.

pub fn memory(&self) -> impl MemoryShared

Returns the memory provider that was configured in the builder.

pub fn reserve(&self, min_bytes: usize) -> BytesBuf

Reserves at least min_bytes bytes of memory capacity.

Returns an empty BytesBuf that can be used to fill the reserved memory with data.

The memory provider may provide more memory than requested.

The memory reservation request will always be fulfilled, obtaining more memory from the operating system if necessary.

Zero-sized reservations

Reserving zero bytes of memory is a valid operation and will return a BytesBuf with zero or more bytes of capacity.

Panics

May panic if the operating system runs out of memory.

Trait Implementations

impl Debug for Null

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Null

fn default() -> Self

Returns the “default value” for a type.

impl HasMemory for Null

fn memory(&self) -> impl MemoryShared

Returns a sharing-compatible memory provider.

impl Memory for Null

fn reserve(&self, min_bytes: usize) -> BytesBuf

Reserves at least min_bytes bytes of memory capacity.

impl Read for Null

type Error = Infallible

Type used to signal errors by the implementation of this trait.

async fn read_at_most_into( &mut self, len: usize, into: BytesBuf, ) -> Result<(usize, BytesBuf), Infallible>

Reads at most len bytes into the provided buffer.

async fn read_more_into( &mut self, into: BytesBuf, ) -> Result<(usize, BytesBuf), Infallible>

Reads an unspecified number of bytes into the provided buffer.

async fn read_any(&mut self) -> Result<BytesBuf, Infallible>

Reads an unspecified number of bytes as a new buffer.

impl Write for Null

type Error = Infallible

Type used to signal errors by the implementation of this trait.

async fn write(&mut self, _sequence: BytesView) -> Result<(), Infallible>

Writes the provided byte sequence.