refactor: build chain extension method (#121)

Co-authored-by: Daan van der Plas <[email protected]>
Co-authored-by: Daanvdplas <[email protected]>

pop-api/src/lib.rs

@@ -1,5 +1,7 @@
 #![cfg_attr(not(feature = "std"), no_std, no_main)]
 
+use ink::env::chain_extension::{ChainExtensionMethod, FromStatusCode};
+
 use constants::DECODING_FAILED;
 use ink::env::chain_extension::FromStatusCode;
 #[cfg(feature = "assets")]
@@ -27,6 +29,22 @@ mod constants {
 	pub(crate) const FUNGIBLES: u8 = 150;
 }
 
+/// Helper method to build `ChainExtensionMethod`.
+///
+/// Parameters:
+/// - 'version': The version of the chain extension
+/// - 'function': The ID of the function
+/// - 'module': The index of the runtime module
+/// - 'dispatchable': The index of the module dispatchable functions
+fn build_extension_method(
+	version: u8,
+	function: u8,
+	module: u8,
+	dispatchable: u8,
+) -> ChainExtensionMethod<(), (), (), false> {
+	ChainExtensionMethod::build(u32::from_le_bytes([version, function, module, dispatchable]))
+}
+
 /// Represents a status code returned by the runtime.
 ///
 /// `StatusCode` encapsulates a `u32` value that indicates the status of an operation performed

pop-api/src/v0/assets/fungibles.rs

@@ -9,6 +9,22 @@ use crate::{
 use constants::*;
 pub use metadata::*;
 
+/// Helper method to build a dispatch call `ChainExtensionMethod` for fungibles `v0`
+///
+/// Parameters:
+/// - 'dispatchable': The index of the module dispatchable functions
+fn build_dispatch(dispatchable: u8) -> ChainExtensionMethod<(), (), (), false> {
+	crate::v0::build_dispatch(FUNGIBLES, dispatchable)
+}
+
+/// Helper method to build a dispatch call `ChainExtensionMethod` for fungibles `v0``
+///
+/// Parameters:
+/// - 'state_query': The index of the runtime state query
+fn build_read_state(state_query: u8) -> ChainExtensionMethod<(), (), (), false> {
+	crate::v0::build_read_state(FUNGIBLES, state_query)
+}
+
 /// Local Fungibles:
 /// 1. PSP-22 Interface
 /// 2. PSP-22 Metadata Interface
@@ -60,7 +76,7 @@ mod constants {
 /// The total supply of the token, or an error if the operation fails.
 #[inline]
 pub fn total_supply(id: AssetId) -> Result<Balance> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, READ_STATE, FUNGIBLES, TOTAL_SUPPLY]))
+	build_read_state(TOTAL_SUPPLY)
 		.input::<AssetId>()
 		.output::<Result<Vec<u8>>, true>()
 		.handle_error_code::<StatusCode>()
@@ -79,7 +95,7 @@ pub fn total_supply(id: AssetId) -> Result<Balance> {
 /// The balance of the specified account, or an error if the operation fails.
 #[inline]
 pub fn balance_of(id: AssetId, owner: AccountId) -> Result<Balance> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, READ_STATE, FUNGIBLES, BALANCE_OF]))
+	build_read_state(BALANCE_OF)
 		.input::<(AssetId, AccountId)>()
 		.output::<Result<Vec<u8>>, true>()
 		.handle_error_code::<StatusCode>()
@@ -99,7 +115,7 @@ pub fn balance_of(id: AssetId, owner: AccountId) -> Result<Balance> {
 /// The remaining allowance, or an error if the operation fails.
 #[inline]
 pub fn allowance(id: AssetId, owner: AccountId, spender: AccountId) -> Result<Balance> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, READ_STATE, FUNGIBLES, ALLOWANCE]))
+	build_read_state(ALLOWANCE)
 		.input::<(AssetId, AccountId, AccountId)>()
 		.output::<Result<Vec<u8>>, true>()
 		.handle_error_code::<StatusCode>()
@@ -119,7 +135,7 @@ pub fn allowance(id: AssetId, owner: AccountId, spender: AccountId) -> Result<Ba
 /// Returns `Ok(())` if successful, or an error if the transfer fails.
 #[inline]
 pub fn transfer(id: AssetId, target: AccountId, amount: Balance) -> Result<()> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, DISPATCH, FUNGIBLES, TRANSFER]))
+	build_dispatch(TRANSFER)
 		.input::<(AssetId, AccountId, Balance)>()
 		.output::<Result<()>, true>()
 		.handle_error_code::<StatusCode>()
@@ -140,7 +156,7 @@ pub fn transfer(id: AssetId, target: AccountId, amount: Balance) -> Result<()> {
 /// Returns `Ok(())` if successful, or an error if the transfer fails.
 #[inline]
 pub fn transfer_from(id: AssetId, from: AccountId, to: AccountId, amount: Balance) -> Result<()> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, DISPATCH, FUNGIBLES, TRANSFER_FROM]))
+	build_dispatch(TRANSFER_FROM)
 		.input::<(AssetId, AccountId, AccountId, Balance)>()
 		.output::<Result<()>, true>()
 		.handle_error_code::<StatusCode>()
@@ -158,7 +174,7 @@ pub fn transfer_from(id: AssetId, from: AccountId, to: AccountId, amount: Balanc
 /// Returns `Ok(())` if successful, or an error if the approval fails.
 #[inline]
 pub fn approve(id: AssetId, spender: AccountId, amount: Balance) -> Result<()> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, DISPATCH, FUNGIBLES, APPROVE]))
+	build_dispatch(APPROVE)
 		.input::<(AssetId, AccountId, Balance)>()
 		.output::<Result<()>, true>()
 		.handle_error_code::<StatusCode>()
@@ -176,7 +192,7 @@ pub fn approve(id: AssetId, spender: AccountId, amount: Balance) -> Result<()> {
 /// Returns `Ok(())` if successful, or an error if the operation fails.
 #[inline]
 pub fn increase_allowance(id: AssetId, spender: AccountId, value: Balance) -> Result<()> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, DISPATCH, FUNGIBLES, INCREASE_ALLOWANCE]))
+	build_dispatch(INCREASE_ALLOWANCE)
 		.input::<(AssetId, AccountId, Balance)>()
 		.output::<Result<()>, true>()
 		.handle_error_code::<StatusCode>()
@@ -194,7 +210,7 @@ pub fn increase_allowance(id: AssetId, spender: AccountId, value: Balance) -> Re
 /// Returns `Ok(())` if successful, or an error if the operation fails.
 #[inline]
 pub fn decrease_allowance(id: AssetId, spender: AccountId, value: Balance) -> Result<()> {
-	ChainExtensionMethod::build(u32::from_le_bytes([V0, DISPATCH, FUNGIBLES, DECREASE_ALLOWANCE]))
+	build_dispatch(DECREASE_ALLOWANCE)
 		.input::<(AssetId, AccountId, Balance)>()
 		.output::<Result<()>, true>()
 		.handle_error_code::<StatusCode>()
@@ -212,7 +228,7 @@ pub mod metadata {
 	/// The name of the token as a byte vector, or an error if the operation fails.
 	#[inline]
 	pub fn token_name(id: AssetId) -> Result<Vec<u8>> {
-		ChainExtensionMethod::build(u32::from_le_bytes([V0, READ_STATE, FUNGIBLES, TOKEN_NAME]))
+		build_read_state(TOKEN_NAME)
 			.input::<AssetId>()
 			.output::<Result<Vec<u8>>, true>()
 			.handle_error_code::<StatusCode>()
@@ -229,7 +245,7 @@ pub mod metadata {
 	///  The symbol of the token as a byte vector, or an error if the operation fails.
 	#[inline]
 	pub fn token_symbol(id: AssetId) -> Result<Vec<u8>> {
-		ChainExtensionMethod::build(u32::from_le_bytes([V0, READ_STATE, FUNGIBLES, TOKEN_SYMBOL]))
+		build_read_state(TOKEN_SYMBOL)
 			.input::<AssetId>()
 			.output::<Result<Vec<u8>>, true>()
 			.handle_error_code::<StatusCode>()
@@ -246,7 +262,7 @@ pub mod metadata {
 	///  The number of decimals of the token as a byte vector, or an error if the operation fails.
 	#[inline]
 	pub fn token_decimals(id: AssetId) -> Result<u8> {
-		ChainExtensionMethod::build(u32::from_le_bytes([V0, READ_STATE, FUNGIBLES, TOKEN_DECIMALS]))
+		build_read_state(TOKEN_DECIMALS)
 			.input::<AssetId>()
 			.output::<Result<Vec<u8>>, true>()
 			.handle_error_code::<StatusCode>()

pop-api/src/v0/assets/mod.rs

@@ -1,2 +1,3 @@
 #[cfg(feature = "fungibles")]
 pub mod fungibles;
+

pop-api/src/v0/mod.rs

@@ -1,4 +1,10 @@
-use crate::{primitives::error::Error, StatusCode};
+use crate::{
+	build_extension_method,
+	constants::{DISPATCH, READ_STATE},
+	primitives::error::Error,
+	StatusCode,
+};
+use ink::env::chain_extension::ChainExtensionMethod;
 
 #[cfg(feature = "assets")]
 pub mod assets;
@@ -10,3 +16,21 @@ impl From<StatusCode> for Error {
 		value.0.into()
 	}
 }
+
+/// Helper method to build a dispatch call `ChainExtensionMethod`
+///
+/// Parameters:
+/// - 'module': The index of the runtime module
+/// - 'dispatchable': The index of the module dispatchable functions
+fn build_dispatch(module: u8, dispatchable: u8) -> ChainExtensionMethod<(), (), (), false> {
+	build_extension_method(V0, DISPATCH, module, dispatchable)
+}
+
+/// Helper method to build a dispatch call `ChainExtensionMethod`
+///
+/// Parameters:
+/// - 'module': The index of the runtime module
+/// - 'state_query': The index of the runtime state query
+fn build_read_state(module: u8, state_query: u8) -> ChainExtensionMethod<(), (), (), false> {
+	build_extension_method(V0, READ_STATE, module, state_query)
+}