allow multi account conversion (polkadot-evm#1295)

primitives/account/src/lib.rs

@@ -20,8 +20,9 @@
 use scale_codec::{Decode, Encode, MaxEncodedLen};
 use scale_info::TypeInfo;
 // Substrate
-use sp_core::{ecdsa, RuntimeDebug, H160, H256};
+use sp_core::{crypto::AccountId32, ecdsa, RuntimeDebug, H160, H256};
 use sp_io::hashing::keccak_256;
+use sp_runtime::MultiSignature;
 use sp_runtime_interface::pass_by::PassByInner;
 
 /// A fully Ethereum-compatible `AccountId`.
@@ -31,7 +32,7 @@ use sp_runtime_interface::pass_by::PassByInner;
 #[derive(Encode, Decode, MaxEncodedLen, TypeInfo)]
 pub struct AccountId20(pub [u8; 20]);
 
-#[cfg(feature = "std")]
+#[cfg(feature = "serde")]
 impl_serde::impl_fixed_hash_serde!(AccountId20, 20);
 
 #[cfg(feature = "std")]
@@ -84,6 +85,19 @@ impl From<[u8; 20]> for AccountId20 {
 	}
 }
 
+impl<'a> TryFrom<&'a [u8]> for AccountId20 {
+	type Error = ();
+	fn try_from(x: &'a [u8]) -> Result<AccountId20, ()> {
+		if x.len() == 20 {
+			let mut data = [0; 20];
+			data.copy_from_slice(x);
+			Ok(AccountId20(data))
+		} else {
+			Err(())
+		}
+	}
+}
+
 impl From<AccountId20> for [u8; 20] {
 	fn from(val: AccountId20) -> Self {
 		val.0
@@ -102,6 +116,30 @@ impl From<AccountId20> for H160 {
 	}
 }
 
+impl AsRef<[u8]> for AccountId20 {
+	fn as_ref(&self) -> &[u8] {
+		&self.0[..]
+	}
+}
+
+impl AsMut<[u8]> for AccountId20 {
+	fn as_mut(&mut self) -> &mut [u8] {
+		&mut self.0[..]
+	}
+}
+
+impl AsRef<[u8; 20]> for AccountId20 {
+	fn as_ref(&self) -> &[u8; 20] {
+		&self.0
+	}
+}
+
+impl AsMut<[u8; 20]> for AccountId20 {
+	fn as_mut(&mut self) -> &mut [u8; 20] {
+		&mut self.0
+	}
+}
+
 impl From<ecdsa::Public> for AccountId20 {
 	fn from(pk: ecdsa::Public) -> Self {
 		let decompressed = libsecp256k1::PublicKey::parse_compressed(&pk.0)
@@ -114,8 +152,23 @@ impl From<ecdsa::Public> for AccountId20 {
 	}
 }
 
-#[cfg_attr(feature = "std", derive(serde::Serialize, serde::Deserialize))]
-#[derive(Eq, PartialEq, Clone, Encode, Decode, RuntimeDebug, TypeInfo)]
+impl From<[u8; 32]> for AccountId20 {
+	fn from(bytes: [u8; 32]) -> Self {
+		let mut buffer = [0u8; 20];
+		buffer.copy_from_slice(&bytes[..20]);
+		Self(buffer)
+	}
+}
+
+impl From<AccountId32> for AccountId20 {
+	fn from(account: AccountId32) -> Self {
+		let bytes: &[u8; 32] = account.as_ref();
+		Self::from(*bytes)
+	}
+}
+
+#[derive(Eq, PartialEq, Clone, RuntimeDebug, Encode, Decode, TypeInfo)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct EthereumSignature(ecdsa::Signature);
 
 impl sp_runtime::traits::Verify for EthereumSignature {
@@ -140,9 +193,23 @@ impl sp_runtime::traits::Verify for EthereumSignature {
 	}
 }
 
+impl From<MultiSignature> for EthereumSignature {
+	fn from(signature: MultiSignature) -> Self {
+		match signature {
+			MultiSignature::Ed25519(_) => {
+				panic!("Ed25519 not supported for EthereumSignature")
+			}
+			MultiSignature::Sr25519(_) => {
+				panic!("Sr25519 not supported for EthereumSignature")
+			}
+			MultiSignature::Ecdsa(sig) => Self(sig),
+		}
+	}
+}
+
 impl EthereumSignature {
 	pub fn new(s: ecdsa::Signature) -> Self {
-		EthereumSignature(s)
+		Self(s)
 	}
 }
 
@@ -223,4 +290,4 @@ mod tests {
 		let account_fmt = format!("{}", account);
 		assert_eq!(account_fmt, "0xE04CC55ebEE1cBCE552f250e85c57B70B2E2625b");
 	}
-}
+}