BREAKING CHANGE: DecodeLimit and DecodeAll extensions now advance inp…

…ut (#314)

* BREAKING CHANGE: DecodeLimit and DecodeAll extensions now properly advance input

* Prepare for release 3.0.0

* This repo uses hard tabs

CHANGELOG.md

@@ -5,8 +5,21 @@ All notable changes to this crate are documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this crate adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## [3.0.0] - 2022-02-02
+
+### Fix
+
+- Optimised the Decode::decode for [T; N] [#299](https://github.com/paritytech/parity-scale-codec/pull/299)
+
+### Changed
+
 - Migrated to 2021 edition, enforcing MSRV of `1.56.1`. [#298](https://github.com/paritytech/parity-scale-codec/pull/298)
+- Upgrade to BitVec 1.0 [#311](https://github.com/paritytech/parity-scale-codec/pull/311)
+- DecodeLimit and DecodeAll extensions now advance input [#314](https://github.com/paritytech/parity-scale-codec/pull/314)
+
+### Added
+
+- Add bytes::Bytes implementation [#309](https://github.com/paritytech/parity-scale-codec/pull/309)
 
 ## [2.3.1] - 2021-09-28
 
@@ -17,6 +30,7 @@ and this crate adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.h
 ## [2.3.0] - 2021-09-11
 
 ### Added
+
 - `decode_and_advance_with_depth_limit` to the `DecodeLimit` trait. This allows advancing the cursor while decoding the input. PR #286
 
 ## [2.2.0] - 2021-07-02

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "parity-scale-codec"
 description = "SCALE - Simple Concatenating Aggregated Little Endians"
-version = "2.3.1"
+version = "3.0.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 license = "Apache-2.0"
 repository = "https://github.com/paritytech/parity-scale-codec"
@@ -12,8 +12,8 @@ rust-version = "1.56.1"
 [dependencies]
 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 = "1", default-features = false, features = ["alloc"], optional = true }
+parity-scale-codec-derive = { path = "derive", version = "3.0.0", default-features = false, optional = true }
+bitvec = { version = "1", default-features = false, features = [ "alloc" ], optional = true }
 bytes = { version = "1", default-features = false, optional = true }
 byte-slice-cast = { version = "1.0.0", default-features = false }
 generic-array = { version = "0.14.4", optional = true }
@@ -59,7 +59,4 @@ chain-error = []
 full = []
 
 [workspace]
-members = [
-	"derive",
-	"fuzzer",
-]
+members = ["derive", "fuzzer"]

derive/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "parity-scale-codec-derive"
 description = "Serialization and deserialization derive macro for Parity SCALE Codec"
-version = "2.3.1"
+version = "3.0.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 license = "Apache-2.0"
 edition = "2021"

rustfmt.toml

@@ -0,0 +1,23 @@
+# Basic
+hard_tabs = true
+max_width = 100
+use_small_heuristics = "Max"
+# Imports
+imports_granularity = "Crate"
+reorder_imports = true
+# Consistency
+newline_style = "Unix"
+# Format comments
+comment_width = 100
+wrap_comments = true
+# Misc
+chain_width = 80
+spaces_around_ranges = false
+binop_separator = "Back"
+reorder_impl_items = false
+match_arm_leading_pipes = "Preserve"
+match_arm_blocks = false
+match_block_trailing_comma = true
+trailing_comma = "Vertical"
+trailing_semicolon = false
+use_field_init_shorthand = true

src/decode_all.rs

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use crate::{Error, Decode};
+use crate::{Decode, Error};
 
 /// The error message returned when `decode_all` fails.
 pub(crate) const DECODE_ALL_ERR_MSG: &str = "Input buffer has still data left after decoding!";
@@ -23,12 +23,11 @@ pub trait DecodeAll: Sized {
 	/// Decode `Self` and consume all of the given input data.
 	///
 	/// If not all data is consumed, an error is returned.
-	fn decode_all(input: &[u8]) -> Result<Self, Error>;
+	fn decode_all(input: &mut &[u8]) -> Result<Self, Error>;
 }
 
 impl<T: Decode> DecodeAll for T {
-	fn decode_all(input: &[u8]) -> Result<Self, Error> {
-		let input = &mut &input[..];
+	fn decode_all(input: &mut &[u8]) -> Result<Self, Error> {
 		let res = T::decode(input)?;
 
 		if input.is_empty() {
@@ -42,7 +41,7 @@ impl<T: Decode> DecodeAll for T {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use crate::{Encode, Input, Compact, EncodeLike};
+	use crate::{Compact, Encode, EncodeLike, Input};
 
 	macro_rules! test_decode_all {
 		(
@@ -51,13 +50,13 @@ mod tests {
 			$(
 				{
 					let mut encoded = <$type as Encode>::encode(&$value);
-					<$type>::decode_all(&encoded).expect(
+					<$type>::decode_all(&mut encoded.as_slice()).expect(
 						&format!("`{} => {}` decodes all!", stringify!($type), stringify!($value)),
 					);
 
 					encoded.extend(&[1, 2, 3, 4, 5, 6]);
 					assert_eq!(
-						<$type>::decode_all(&encoded).unwrap_err().to_string(),
+						<$type>::decode_all(&mut encoded.as_slice()).unwrap_err().to_string(),
 						"Input buffer has still data left after decoding!",
 					);
 				}
@@ -86,13 +85,11 @@ mod tests {
 
 	impl Decode for TestStruct {
 		fn decode<I: Input>(input: &mut I) -> Result<Self, Error> {
-			Ok(
-				Self {
-					data: Vec::<u32>::decode(input)?,
-					other: u8::decode(input)?,
-					compact: Compact::<u128>::decode(input)?,
-				}
-			)
+			Ok(Self {
+				data: Vec::<u32>::decode(input)?,
+				other: u8::decode(input)?,
+				compact: Compact::<u128>::decode(input)?,
+			})
 		}
 	}
 

src/depth_limit.rs

@@ -12,37 +12,32 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use crate::{Error, Decode, Input};
+use crate::{Decode, Error, Input};
 
 /// The error message returned when depth limit is reached.
 const DECODE_MAX_DEPTH_MSG: &str = "Maximum recursion depth reached when decoding";
 
 /// Extension trait to [`Decode`] for decoding with a maximum recursion depth.
 pub trait DecodeLimit: Sized {
-	/// Decode `Self` with the given maximum recursion depth.
+	/// Decode `Self` with the given maximum recursion depth and advance `input` by the number of
+	/// bytes consumed.
 	///
 	/// If `limit` is hit, an error is returned.
-	fn decode_with_depth_limit(limit: u32, input: &[u8]) -> Result<Self, Error>;
-
-	/// Decode `Self` and advance `input` by the number of bytes consumed.
-	///
-	/// If `limit` is hit, an error is returned.
-	fn decode_and_advance_with_depth_limit<I: Input>(limit: u32, input: &mut I) -> Result<Self, Error>;
+	fn decode_with_depth_limit<I: Input>(limit: u32, input: &mut I) -> Result<Self, Error>;
 
 	/// Decode `Self` and consume all of the given input data.
 	///
 	/// If not all data is consumed or `limit` is hit, an error is returned.
-	fn decode_all_with_depth_limit(limit: u32, input: &[u8]) -> Result<Self, Error>;
+	fn decode_all_with_depth_limit(limit: u32, input: &mut &[u8]) -> Result<Self, Error>;
 }
 
-
 struct DepthTrackingInput<'a, I> {
 	input: &'a mut I,
 	depth: u32,
 	max_depth: u32,
 }
 
-impl<'a, I:Input> Input for DepthTrackingInput<'a, I> {
+impl<'a, I: Input> Input for DepthTrackingInput<'a, I> {
 	fn remaining_len(&mut self) -> Result<Option<usize>, Error> {
 		self.input.remaining_len()
 	}
@@ -72,36 +67,18 @@ impl<'a, I:Input> Input for DepthTrackingInput<'a, I> {
 }
 
 impl<T: Decode> DecodeLimit for T {
-	fn decode_all_with_depth_limit(limit: u32, input: &[u8]) -> Result<Self, Error> {
-		let mut input = DepthTrackingInput {
-			input: &mut &input[..],
-			depth: 0,
-			max_depth: limit,
-		};
-		let res = T::decode(&mut input)?;
-
-		if input.input.is_empty() {
-			Ok(res)
+	fn decode_all_with_depth_limit(limit: u32, input: &mut &[u8]) -> Result<Self, Error> {
+		let t = <Self as DecodeLimit>::decode_with_depth_limit(limit, input)?;
+
+		if input.is_empty() {
+			Ok(t)
 		} else {
 			Err(crate::decode_all::DECODE_ALL_ERR_MSG.into())
 		}
 	}
 
-	fn decode_and_advance_with_depth_limit<I: Input>(limit: u32, input: &mut I) -> Result<Self, Error> {
-		let mut input = DepthTrackingInput {
-			input,
-			depth: 0,
-			max_depth: limit,
-		};
-		T::decode(&mut input)
-	}
-
-	fn decode_with_depth_limit(limit: u32, input: &[u8]) -> Result<Self, Error> {
-		let mut input = DepthTrackingInput {
-			input: &mut &input[..],
-			depth: 0,
-			max_depth: limit,
-		};
+	fn decode_with_depth_limit<I: Input>(limit: u32, input: &mut I) -> Result<Self, Error> {
+		let mut input = DepthTrackingInput { input, depth: 0, max_depth: limit };
 		T::decode(&mut input)
 	}
 }
@@ -117,19 +94,38 @@ mod tests {
 		let nested: NestedVec = vec![vec![vec![vec![1]]]];
 		let encoded = nested.encode();
 
-		let decoded = NestedVec::decode_with_depth_limit(3, &encoded).unwrap();
+		let decoded = NestedVec::decode_with_depth_limit(3, &mut encoded.as_slice()).unwrap();
 		assert_eq!(decoded, nested);
-		assert!(NestedVec::decode_with_depth_limit(2, &encoded).is_err());
+		assert!(NestedVec::decode_with_depth_limit(2, &mut encoded.as_slice()).is_err());
 	}
 
 	#[test]
-	fn decode_and_advance_works() {
+	fn decode_limit_advances_input() {
 		type NestedVec = Vec<Vec<Vec<Vec<u8>>>>;
 		let nested: NestedVec = vec![vec![vec![vec![1]]]];
-		let encoded = &mut &nested.encode()[..];
+		let encoded = nested.encode();
+		let encoded_slice = &mut encoded.as_slice();
 
-		let decoded = Vec::<u8>::decode_and_advance_with_depth_limit(1, encoded).unwrap();
+		let decoded = Vec::<u8>::decode_with_depth_limit(1, encoded_slice).unwrap();
 		assert_eq!(decoded, vec![4]);
-		assert!(NestedVec::decode_with_depth_limit(3, encoded).is_err());
+		assert!(NestedVec::decode_with_depth_limit(3, encoded_slice).is_err());
+	}
+
+	#[test]
+	fn decode_all_with_limit_advances_input() {
+		type NestedVec = Vec<Vec<Vec<Vec<u8>>>>;
+		let nested: NestedVec = vec![vec![vec![vec![1]]]];
+		let mut encoded = NestedVec::encode(&nested);
+
+		let decoded = NestedVec::decode_all_with_depth_limit(3, &mut encoded.as_slice()).unwrap();
+		assert_eq!(decoded, nested);
+
+		encoded.extend(&[1, 2, 3, 4, 5, 6]);
+		assert_eq!(
+			NestedVec::decode_all_with_depth_limit(3, &mut encoded.as_slice())
+				.unwrap_err()
+				.to_string(),
+			"Input buffer has still data left after decoding!",
+		);
 	}
 }