refactor(target_chains/starknet): move ByteArray to a separate module

Author: Riateche

target_chains/starknet/contracts/src/byte_array.cairo

@@ -0,0 +1,64 @@
+use core::fmt::{Debug, Formatter};
+
+/// A byte array with storage format similar to `core::ByteArray`, but
+/// suitable for reading data from it.
+#[derive(Drop, Clone, Serde)]
+pub struct ByteArray {
+    // Number of bytes stored in the last item of `self.data` (or 0 if it's empty).
+    num_last_bytes: u8,
+    // Bytes in big endian. Each item except the last one stores 31 bytes.
+    // If `num_last_bytes < 31`, unused most significant bytes of the last item will be unused.
+    data: Array<bytes31>,
+}
+
+impl DebugByteArray of Debug<ByteArray> {
+    fn fmt(self: @ByteArray, ref f: Formatter) -> Result<(), core::fmt::Error> {
+        write!(f, "ByteArray {{ num_last_bytes: {}, data: [", self.num_last_bytes)?;
+        let mut data = self.data.clone();
+        loop {
+            match data.pop_front() {
+                Option::Some(v) => {
+                    let v: u256 = v.into();
+                    write!(f, "{:?}, ", v).unwrap();
+                },
+                Option::None => { break; },
+            }
+        };
+        write!(f, "]}}")
+    }
+}
+
+#[generate_trait]
+pub impl ByteArrayImpl of ByteArrayTrait {
+    /// Creates a byte array with the data.
+    fn new(data: Array<bytes31>, num_last_bytes: u8) -> ByteArray {
+        if data.len() == 0 {
+            assert!(num_last_bytes == 0);
+        } else {
+            assert!(num_last_bytes <= 31);
+        // TODO: check that unused bytes are zeroed.
+        }
+        ByteArray { num_last_bytes, data }
+    }
+
+    /// Removes 31 or less bytes from the start of the array.
+    /// Returns the value and the number of bytes.
+    fn pop_front(ref self: ByteArray) -> Option<(bytes31, u8)> {
+        let item = self.data.pop_front()?;
+        if self.data.is_empty() {
+            let num_bytes = self.num_last_bytes;
+            self.num_last_bytes = 0;
+            Option::Some((item, num_bytes))
+        } else {
+            Option::Some((item, 31))
+        }
+    }
+
+    fn len(self: @ByteArray) -> usize {
+        if self.data.is_empty() {
+            0
+        } else {
+            (self.data.len() - 1) * 31 + (*self.num_last_bytes).into()
+        }
+    }
+}

target_chains/starknet/contracts/src/lib.cairo

@@ -1,5 +1,6 @@
 pub mod pyth;
 pub mod wormhole;
+pub mod byte_array;
 pub mod reader;
 pub mod hash;
 pub mod util;

target_chains/starknet/contracts/src/merkle_tree.cairo

@@ -1,5 +1,6 @@
 use super::hash::{Hasher, HasherImpl};
-use super::reader::{Reader, ReaderImpl, ByteArray};
+use super::reader::{Reader, ReaderImpl};
+use super::byte_array::ByteArray;
 use super::util::ONE_SHIFT_96;
 use core::cmp::{min, max};
 

target_chains/starknet/contracts/src/reader.cairo

@@ -4,6 +4,7 @@ use core::keccak::cairo_keccak;
 use core::integer::u128_byte_reverse;
 use core::fmt::{Debug, Formatter};
 use pyth::util::{UNEXPECTED_OVERFLOW, UNEXPECTED_ZERO, one_shift_left_bytes_u128};
+use super::byte_array::{ByteArray, ByteArrayImpl};
 
 #[derive(Copy, Drop, Debug, Serde, PartialEq)]
 pub enum Error {
@@ -18,69 +19,6 @@ impl ErrorIntoFelt252 of Into<Error, felt252> {
     }
 }
 
-/// A byte array with storage format similar to `core::ByteArray`, but
-/// suitable for reading data from it.
-#[derive(Drop, Clone, Serde)]
-pub struct ByteArray {
-    // Number of bytes stored in the last item of `self.data` (or 0 if it's empty).
-    num_last_bytes: u8,
-    // Bytes in big endian. Each item except the last one stores 31 bytes.
-    // If `num_last_bytes < 31`, unused most significant bytes of the last item will be unused.
-    data: Array<bytes31>,
-}
-
-impl DebugByteArray of Debug<ByteArray> {
-    fn fmt(self: @ByteArray, ref f: Formatter) -> Result<(), core::fmt::Error> {
-        write!(f, "ByteArray {{ num_last_bytes: {}, data: [", self.num_last_bytes)?;
-        let mut data = self.data.clone();
-        loop {
-            match data.pop_front() {
-                Option::Some(v) => {
-                    let v: u256 = v.into();
-                    write!(f, "{:?}, ", v).unwrap();
-                },
-                Option::None => { break; },
-            }
-        };
-        write!(f, "]}}")
-    }
-}
-
-#[generate_trait]
-pub impl ByteArrayImpl of ByteArrayTrait {
-    /// Creates a byte array with the data.
-    fn new(data: Array<bytes31>, num_last_bytes: u8) -> ByteArray {
-        if data.len() == 0 {
-            assert!(num_last_bytes == 0);
-        } else {
-            assert!(num_last_bytes <= 31);
-        // TODO: check that unused bytes are zeroed.
-        }
-        ByteArray { num_last_bytes, data }
-    }
-
-    /// Removes 31 or less bytes from the start of the array.
-    /// Returns the value and the number of bytes.
-    fn pop_front(ref self: ByteArray) -> Option<(bytes31, u8)> {
-        let item = self.data.pop_front()?;
-        if self.data.is_empty() {
-            let num_bytes = self.num_last_bytes;
-            self.num_last_bytes = 0;
-            Option::Some((item, num_bytes))
-        } else {
-            Option::Some((item, 31))
-        }
-    }
-
-    fn len(self: @ByteArray) -> usize {
-        if self.data.is_empty() {
-            0
-        } else {
-            (self.data.len() - 1) * 31 + (*self.num_last_bytes).into()
-        }
-    }
-}
-
 /// Allows to read data from a byte array as big endian integers.
 /// All methods return `EOF` error if attempted to
 /// read more bytes than is available.

target_chains/starknet/contracts/src/wormhole.cairo

@@ -1,4 +1,4 @@
-use pyth::reader::ByteArray;
+use super::byte_array::ByteArray;
 use core::starknet::secp256_trait::Signature;
 use pyth::util::UnwrapWithFelt252;
 
@@ -114,7 +114,8 @@ mod wormhole {
     use super::{
         VM, IWormhole, GuardianSignature, quorum, ParseAndVerifyVmError, SubmitNewGuardianSetError
     };
-    use pyth::reader::{Reader, ReaderImpl, ByteArray};
+    use pyth::reader::{Reader, ReaderImpl};
+    use pyth::byte_array::ByteArray;
     use core::starknet::secp256_trait::{Signature, recover_public_key, Secp256PointTrait};
     use core::starknet::secp256k1::Secp256k1Point;
     use core::starknet::{

target_chains/starknet/contracts/tests/wormhole.cairo

@@ -1,6 +1,7 @@
 use snforge_std::{declare, ContractClassTrait, start_prank, stop_prank, CheatTarget};
 use pyth::wormhole::{IWormholeDispatcher, IWormholeDispatcherTrait, ParseAndVerifyVmError};
-use pyth::reader::{ByteArray, ByteArrayImpl, ReaderImpl};
+use pyth::reader::ReaderImpl;
+use pyth::byte_array::{ByteArray, ByteArrayImpl};
 use pyth::util::{UnwrapWithFelt252, array_felt252_to_bytes31};
 use core::starknet::ContractAddress;
 use core::panic_with_felt252;