Bump bitvec dependency to 0.22.3

There was a conflict between bitvec and a dependency of it (funty) that
caused a build failure. See:
- ferrilab/bitvec#105
- ferrilab/funty#3

Due to semver, when importing parity-scale-codec as a library and
resolving bitvec 0.20.1 dependencies, funty 0.12 is pulled, which causes
the aforementioned build failure.  I believe this is not happening when
testing parity-scale-codec itself because Cargo.lock pins funty to
1.1.0, but when importing parity-scale-codec from another crate, this
pinning is sometimes not possible.  Bumping bitvec to 0.22.3 solves this
issue, as it is compatible with funty 0.12.

Cargo.toml

@@ -12,7 +12,7 @@ edition = "2018"
 arrayvec = { version = "0.7", default-features = false }
 serde = { version = "1.0.102", optional = true }
 parity-scale-codec-derive = { path = "derive", version = "2.3.1", default-features = false, optional = true }
-bitvec = { version = "0.20.1", default-features = false, features = ["alloc"], optional = true }
+bitvec = { version = "0.22.3", default-features = false, features = ["alloc"], optional = true }
 byte-slice-cast = { version = "1.0.0", default-features = false }
 generic-array = { version = "0.14.4", optional = true }
 arbitrary = { version = "1.0.1", features = ["derive"], optional = true }

fuzzer/Cargo.toml

@@ -9,4 +9,4 @@ publish = false
 parity-scale-codec = { path = "..", features = ["derive", "bit-vec", "fuzz"] }
 honggfuzz = "0.5.54"
 arbitrary = { version = "1.0.1", features = ["derive"] }
-bitvec = { version = "0.20.1", features = ["alloc"] }
+bitvec = { version = "0.22.3", features = ["alloc"] }

src/bit_vec.rs

@@ -15,7 +15,8 @@
 //! `BitVec` specific serialization.
 
 use bitvec::{
-	vec::BitVec, store::BitStore, order::BitOrder, slice::BitSlice, boxed::BitBox, mem::BitMemory
+	boxed::BitBox, order::BitOrder, slice::BitSlice, store::BitStore, vec::BitVec,
+	view::BitViewSized,
 };
 use crate::{
 	EncodeLike, Encode, Decode, Input, Output, Error, Compact,
@@ -31,11 +32,11 @@ impl<O: BitOrder, T: BitStore + Encode> Encode for BitSlice<O, T> {
 		);
 		Compact(len as u32).encode_to(dest);
 
-		// NOTE: doc of `BitSlice::as_slice`:
+		// NOTE: doc of `BitSlice::as_raw_slice`:
 		// > The returned slice handle views all elements touched by self
 		//
 		// Thus we are sure the slice doesn't contain unused elements at the end.
-		let slice = self.as_slice();
+		let slice = self.as_raw_slice();
 
 		encode_slice_no_len(slice, dest)
 	}
@@ -97,7 +98,7 @@ impl<O: BitOrder, T: BitStore + Decode> Decode for BitBox<O, T> {
 /// NOTE: this should never happen if `bits` is already checked to be less than
 /// `BitStore::MAX_BITS`.
 fn required_elements<T: BitStore>(bits: u32) -> Result<u32, Error> {
-	let element_bits = T::Mem::BITS as u32;
+	let element_bits = T::BITS as u32;
 	let error = Error::from("Attempt to decode bitvec with too many bits");
 	Ok((bits.checked_add(element_bits).ok_or_else(|| error)?  - 1) / element_bits)
 }
@@ -170,6 +171,10 @@ mod tests {
 	}
 
 	#[test]
+	// Flaky test due to:
+	// * https://github.com/bitvecto-rs/bitvec/issues/135
+	// * https://github.com/rust-lang/miri/issues/1866
+	#[cfg(not(miri))]
 	fn bitvec_u8() {
 		for v in &test_data!(u8) {
 			let encoded = v.encode();
@@ -182,7 +187,6 @@ mod tests {
 	// * https://github.com/bitvecto-rs/bitvec/issues/135
 	// * https://github.com/rust-lang/miri/issues/1866
 	#[cfg(not(miri))]
-
 	fn bitvec_u16() {
 		for v in &test_data!(u16) {
 			let encoded = v.encode();