From 68058b4890a6ade3cb0d3aee26f23609e5b658fb Mon Sep 17 00:00:00 2001
From: Yaroslav Bolyukin <iam@lach.pw>
Date: Tue, 12 Jul 2022 16:51:57 +0000
Subject: [PATCH] doc(pallet-evm-migration): document public api


---
--- /dev/null
+++ b/pallets/evm-migration/README.md
@@ -0,0 +1,18 @@
+# EVM contract migration pallet
+
+This pallet is only callable by root, it has functionality to migrate contract
+from other ethereum chain to pallet-evm
+
+Contract data includes contract code, and contract storage,
+where contract storage is a mapping from evm word to evm word (evm word = 32 byte)
+
+To import contract data into pallet-evm admin should call this pallet multiple times:
+1. Start migration via `begin`
+2. Insert all contract data using single or
+   multiple (If data can't be fit into single extrinsic) calls
+   to `set_data`
+3. Finish migration using `finish`, providing contract code
+
+During migration no one can insert code at address of this contract,
+as [`pallet::OnMethodCall`] prevents this, and no one can call this contract,
+as code is only supplied at final stage of contract deployment
\ No newline at end of file
--- a/pallets/evm-migration/src/benchmarking.rs
+++ b/pallets/evm-migration/src/benchmarking.rs
@@ -14,6 +14,8 @@
 // You should have received a copy of the GNU General Public License
 // along with Unique Network. If not, see <http://www.gnu.org/licenses/>.
 
+#![allow(missing_docs)]
+
 use super::{Call, Config, Pallet};
 use frame_benchmarking::benchmarks;
 use frame_system::RawOrigin;
--- a/pallets/evm-migration/src/lib.rs
+++ b/pallets/evm-migration/src/lib.rs
@@ -14,7 +14,9 @@
 // You should have received a copy of the GNU General Public License
 // along with Unique Network. If not, see <http://www.gnu.org/licenses/>.
 
+#![doc = include_str!("../README.md")]
 #![cfg_attr(not(feature = "std"), no_std)]
+#![deny(missing_docs)]
 
 pub use pallet::*;
 #[cfg(feature = "runtime-benchmarks")]
@@ -32,6 +34,7 @@
 
 	#[pallet::config]
 	pub trait Config: frame_system::Config + pallet_evm::Config {
+		/// Weights
 		type WeightInfo: WeightInfo;
 	}
 
@@ -43,7 +46,9 @@
 
 	#[pallet::error]
 	pub enum Error<T> {
+		/// Can only migrate to empty address.
 		AccountNotEmpty,
+		/// Migration of this account is not yet started, or already finished.
 		AccountIsNotMigrating,
 	}
 
@@ -53,6 +58,8 @@
 
 	#[pallet::call]
 	impl<T: Config> Pallet<T> {
+		/// Start contract migration, inserts contract stub at target address,
+		/// and marks account as pending, allowing to insert storage
 		#[pallet::weight(<SelfWeightOf<T>>::begin())]
 		pub fn begin(origin: OriginFor<T>, address: H160) -> DispatchResult {
 			ensure_root(origin)?;
@@ -65,6 +72,8 @@
 			Ok(())
 		}
 
+		/// Insert items into contract storage, this method can be called
+		/// multiple times
 		#[pallet::weight(<SelfWeightOf<T>>::set_data(data.len() as u32))]
 		pub fn set_data(
 			origin: OriginFor<T>,
@@ -83,6 +92,9 @@
 			Ok(())
 		}
 
+		/// Finish contract migration, allows it to be called.
+		/// It is not possible to alter contract storage via [`Self::set_data`]
+		/// after this call.
 		#[pallet::weight(<SelfWeightOf<T>>::finish(code.len() as u32))]
 		pub fn finish(origin: OriginFor<T>, address: H160, code: Vec<u8>) -> DispatchResult {
 			ensure_root(origin)?;
@@ -97,6 +109,7 @@
 		}
 	}
 
+	/// Implements [`pallet_evm::OnMethodCall`], which reserves accounts with pending migration
 	pub struct OnMethodCall<T>(PhantomData<T>);
 	impl<T: Config> pallet_evm::OnMethodCall<T> for OnMethodCall<T> {
 		fn is_reserved(contract: &H160) -> bool {
--- a/pallets/evm-migration/src/weights.rs
+++ b/pallets/evm-migration/src/weights.rs
@@ -26,6 +26,7 @@
 #![cfg_attr(rustfmt, rustfmt_skip)]
 #![allow(unused_parens)]
 #![allow(unused_imports)]
+#![allow(missing_docs)]
 #![allow(clippy::unnecessary_cast)]
 
 use frame_support::{traits::Get, weights::{Weight, constants::RocksDbWeight}};

-- 
gitstuff