pub mod common;
use std::num::NonZero;
use common::{
field::huffman::{self, Reference as _},
wire::integer,
};
use o3::buffer::{
storage,
write::{Slice, SpareExt as _},
};
use sark_http::field::metadata::{
huffman::{
decoder::{self, DecodeError, Decoder},
source::{Encoded, Source},
},
integer::{Error, Overflow, PrefixedInt, Width},
};
#[test]
fn rfc_authority() {
let raw = huffman::AUTHORITY;
let expected = huffman::AUTHORITY_ENCODED;
let source = Source::new(raw)
.try_measure()
.expect("representable encoding");
let mut encoded = Vec::with_capacity(source.encoded_len());
source.encode(&mut encoded);
assert_eq!(source.encoded_len(), expected.len());
assert_eq!(encoded, expected);
assert!(matches!(Encoded::new(&encoded).decode(Vec::new()), Ok(decoded) if decoded == raw));
}
#[test]
fn every_symbol_round_trips() {
let raw: Vec<u8> = (0..=u8::MAX).collect();
let source = Source::new(&raw)
.try_measure()
.expect("representable encoding");
let mut encoded = Vec::new();
source.encode(&mut encoded);
assert_eq!(source.encoded_len(), encoded.len());
assert!(matches!(Encoded::new(&encoded).decode(Vec::new()), Ok(decoded) if decoded == raw));
assert!(matches!(Encoded::new(&encoded).decoded_len(), Ok(len) if len == raw.len()));
}
#[test]
fn split_state_round_trips() {
let raw: Vec<u8> = (0..=u8::MAX).collect();
let source = Source::new(&raw);
let mut encoded = Vec::new();
source.encode(&mut encoded);
for split in 0..=encoded.len() {
let (decoder, decoded, head) = (Decoder::new()
.feed_into(&encoded[..split], Vec::new())
.map(|output| output.into_parts())
.map_err(|failure| {
(
failure.cause,
failure.progress.consumed(),
failure.progress.decoded(),
)
}))
.expect("valid encoded prefix must decode");
let (decoder, decoded, tail) = (decoder
.feed_into(&encoded[split..], decoded)
.map(|output| output.into_parts())
.map_err(|failure| {
(
failure.cause,
failure.progress.consumed(),
failure.progress.decoded(),
)
}))
.expect("valid encoded suffix must decode");
(decoder.finish())
.as_ref()
.expect("test operation must succeed");
assert_eq!(head + tail, raw.len());
assert_eq!(decoded, raw, "split at encoded byte {split}");
let (counter, first) = (Decoder::new().feed_count(&encoded[..split]))
.expect("valid encoded prefix must count");
let (counter, second) =
(counter.feed_count(&encoded[split..])).expect("valid encoded suffix must count");
(counter.finish())
.as_ref()
.expect("test operation must succeed");
assert_eq!(
first + second,
raw.len(),
"count split at encoded byte {split}"
);
}
}
#[test]
fn rejects_eos_padding() {
for encoded in huffman::BAD_TAILS {
assert!(
Encoded::new(encoded).decode(Vec::new())
== Err(DecodeError::InvalidEncoding(decoder::Error))
);
}
}
#[test]
fn separates_sink_failure() {
let mut encoded = Vec::new();
Source::new(huffman::SHORT).encode(&mut encoded);
let failure = Encoded::new(&encoded)
.decode_with(Err::<(), _>)
.expect_err("failing sink must reject the encoded input");
assert!(failure.cause == DecodeError::Sink(b'a'));
assert_eq!(failure.progress.consumed(), 0);
assert_eq!(failure.progress.decoded(), 0);
}
#[test]
fn owner_paths_match() {
let raw = huffman::RETAINED;
let mut encoded = Vec::new();
Source::new(raw).encode(&mut encoded);
let encoded = Encoded::new(&encoded);
assert!(matches!(encoded.decoded_len(), Ok(len) if len == raw.len()));
let mut owner =
(storage::Owned::try_with(raw.len() + 16)).expect("the destination must allocate");
let mut writer = owner.spare();
let bounded = writer.bounded();
let (bounded, decoded) = encoded
.write_to(bounded)
.map_err(|failure| {
(
failure.cause,
failure.progress.consumed(),
failure.progress.decoded(),
)
})
.expect("valid input must fit its output owner");
assert_eq!(decoded, raw.len());
bounded.commit();
writer.commit();
assert_eq!(owner.as_slice(), raw);
}
#[test]
fn short_owner_rolls_back() {
let mut encoded = Vec::new();
Source::new(huffman::LONG).encode(&mut encoded);
let mut owner =
(storage::Owned::try_with(3)).expect("the three-byte destination must allocate");
let mut writer = owner.spare();
{
let failure = (Encoded::new(&encoded).write_to(writer.bounded()))
.err()
.expect("the bounded sink must reject longer output");
let error = match failure.cause {
DecodeError::Sink(error) => Some(error),
_ => None,
}
.expect("valid encoding must fail at the bounded sink");
assert_eq!(error.into_parts(), (NonZero::<usize>::MIN, 0));
assert_eq!(failure.progress.decoded(), 3);
assert!(failure.progress.consumed() < encoded.len());
}
assert_eq!(writer.len(), 0);
assert!(owner.as_slice().is_empty());
}
#[test]
fn invalid_owner_rolls_back() {
let invalid = huffman::INVALID;
let mut owner =
(storage::Owned::try_with(16)).expect("the sixteen-byte destination must allocate");
let mut writer = owner.spare();
{
let failure = (Encoded::new(invalid).write_to(writer.bounded()))
.err()
.expect("invalid input must be rejected");
assert!(matches!(
failure.cause,
DecodeError::InvalidEncoding(decoder::Error)
));
assert_eq!(failure.progress.decoded(), 3);
assert!(failure.progress.consumed() < invalid.len());
}
assert_eq!(writer.len(), 0);
assert!(owner.as_slice().is_empty());
}
#[test]
fn keeps_prefix() {
let mut out = Vec::with_capacity(huffman::PREFIX.len() + huffman::AUTHORITY.len());
out.extend_from_slice(huffman::PREFIX);
let pointer = out.as_ptr();
let out = Encoded::new(huffman::AUTHORITY_ENCODED)
.decode(out)
.expect("valid encoded suffix");
assert_eq!(out.as_ptr(), pointer);
assert_eq!(&out[..huffman::PREFIX.len()], huffman::PREFIX);
assert_eq!(&out[huffman::PREFIX.len()..], huffman::AUTHORITY);
}
#[test]
fn dfa_matches_reference() {
for byte in 0..=u8::MAX {
let input = [byte];
assert!(
Encoded::new(&input).decode(Vec::new())
== input.try_decode().map_err(DecodeError::InvalidEncoding),
"{input:02x?}"
);
}
let mut random = 0x9e37_79b9_7f4a_7c15u64;
let mut input = [0u8; 8];
for case in 0..8192usize {
random ^= random << 13;
random ^= random >> 7;
random ^= random << 17;
let len = case % input.len() + 1;
for byte in &mut input[..len] {
random ^= random << 13;
random ^= random >> 7;
random ^= random << 17;
*byte = random as u8;
}
assert!(
Encoded::new(&input[..len]).decode(Vec::new())
== input[..len]
.try_decode()
.map_err(DecodeError::InvalidEncoding),
"{:02x?}",
&input[..len]
);
}
}
#[test]
fn roundtrips_boundaries() {
check::<1>(0x80);
check::<2>(0x80);
check::<3>(0x80);
check::<4>(0x80);
check::<5>(0x80);
check::<6>(0x80);
check::<7>(0x80);
check::<8>(0x00);
}
#[test]
fn separates_decode_errors() {
for bytes in [integer::TRUNCATED, integer::OVERFLOW] {
let mut input = bytes;
assert!(
PrefixedInt::<5>::take(&mut input)
== PrefixedInt::<5>::decode(bytes).map(|(value, _)| value)
);
assert_eq!(input, bytes);
}
assert!(PrefixedInt::<5>::decode(integer::TRUNCATED) == Err(Error::NeedMore));
assert!(
PrefixedInt::<5>::decode(integer::OVERFLOW)
== Err(Error::Overflow(Overflow {
value: (1 << 63) + 30,
shift: 63,
byte: 1,
}))
);
let mut bytes = [0x80; 11];
bytes[0] = 0x1f;
for terminal in 2..=0x7f {
bytes[10] = terminal;
assert!(
PrefixedInt::<5>::decode(&bytes)
== Err(Error::Overflow(Overflow {
value: 31,
shift: 63,
byte: terminal,
})),
"terminal {terminal:#x} must not lose its high bits at shift 63",
);
}
}
#[test]
fn preserves_write_error() {
let mut bytes = [0xa5; 3];
let mut output = Slice::new(&mut bytes[..2]);
let error = PrefixedInt::<5>::new(1337)
.try_encode(0, &mut output)
.expect_err("third byte exceeds the output");
assert_eq!(error.into_parts(), (NonZero::<usize>::MIN, 0));
assert_eq!(output.finish(), 2);
assert_eq!(bytes, [31, 154, 0xa5]);
}
fn check<const BITS: u8>(prefix: u8)
where
PrefixedInt<BITS>: Width,
{
for &value in integer::VALUES {
let integer = PrefixedInt::<BITS>::new(value);
let mut encoded = Vec::new();
integer.encode(prefix, &mut encoded);
assert_eq!(integer.encoded_len().get(), encoded.len());
assert!(PrefixedInt::<BITS>::decode(&encoded) == Ok((integer, integer.encoded_len())));
assert_eq!(integer.pack::<11>(prefix).as_ref(), encoded);
let mut bytes = [0; 11];
let mut output = Slice::new(&mut bytes);
integer.try_encode(prefix, &mut output).expect("wire bytes");
let written = output.finish();
assert_eq!(&bytes[..written], encoded);
encoded.push(0xa5);
let mut input = encoded.as_slice();
assert!(PrefixedInt::<BITS>::take(&mut input) == Ok(integer));
assert_eq!(input, &[0xa5]);
}
}