Move runtime upgrade to frame-executive (#5197)

* Move runtime upgrade to `frame-executive`

Instead of storing the runtime upgraded in the space of `frame-system`,
this moves it to `frame-executive`. We also start storing the
`spec_version` and `impl_version` the last runtime upgrade was applied.

This scheme has multiple advantages:
- We don't need to make sure that runtime upgrade was set.
- This will work in the future when we want to test a runtime upgrade,
because the `on_runtime_upgrade` will be executed automatically when the
runtime changes.

* Move `LAST_RUNTIME_UPGRADE` key to `frame-executive`

* Add some more documentation

* Make sure `spec_version` always increases between runtime upgrades

* Fix test

* Upgrade `parity-multiaddr` to fix compilation

* Also check if the `spec_name` changed

* Remove `RuntimeUpgraded` storage entry

* Don't run on genesis

substrate/frame/system/src/lib.rs

@@ -307,6 +307,33 @@ pub struct AccountInfo<Index, AccountData> {
 	pub data: AccountData,
 }
 
+/// Stores the `spec_version` and `spec_name` of when the last runtime upgrade
+/// happened.
+#[derive(sp_runtime::RuntimeDebug, Encode, Decode)]
+#[cfg_attr(feature = "std", derive(PartialEq))]
+pub struct LastRuntimeUpgradeInfo {
+	pub spec_version: codec::Compact<u32>,
+	pub spec_name: sp_runtime::RuntimeString,
+}
+
+impl LastRuntimeUpgradeInfo {
+	/// Returns if the runtime was upgraded in comparison of `self` and `current`.
+	///
+	/// Checks if either the `spec_version` increased or the `spec_name` changed.
+	pub fn was_upgraded(&self, current: &sp_version::RuntimeVersion) -> bool {
+		current.spec_version > self.spec_version.0 || current.spec_name != self.spec_name
+	}
+}
+
+impl From<sp_version::RuntimeVersion> for LastRuntimeUpgradeInfo {
+	fn from(version: sp_version::RuntimeVersion) -> Self {
+		Self {
+			spec_version: version.spec_version.into(),
+			spec_name: version.spec_name,
+		}
+	}
+}
+
 decl_storage! {
 	trait Store for Module<T: Trait> as System {
 		/// The full account information for a particular account ID.
@@ -368,8 +395,8 @@ decl_storage! {
 		/// no notification will be triggered thus the event might be lost.
 		EventTopics get(fn event_topics): map hasher(blake2_256) T::Hash => Vec<(T::BlockNumber, EventIndex)>;
 
-		/// A bool to track if the runtime was upgraded last block.
-		pub RuntimeUpgraded: bool;
+		/// Stores the `spec_version` and `spec_name` of when the last runtime upgrade happened.
+		pub LastRuntimeUpgrade build(|_| Some(LastRuntimeUpgradeInfo::from(T::Version::get()))): Option<LastRuntimeUpgradeInfo>;
 	}
 	add_extra_genesis {
 		config(changes_trie_config): Option<ChangesTrieConfiguration>;
@@ -416,13 +443,7 @@ decl_error! {
 		InvalidSpecName,
 		/// The specification version is not allowed to decrease between the current runtime
 		/// and the new runtime.
-		SpecVersionNotAllowedToDecrease,
-		/// The implementation version is not allowed to decrease between the current runtime
-		/// and the new runtime.
-		ImplVersionNotAllowedToDecrease,
-		/// The specification or the implementation version need to increase between the
-		/// current runtime and the new runtime.
-		SpecOrImplVersionNeedToIncrease,
+		SpecVersionNeedsToIncrease,
 		/// Failed to extract the runtime version from the new runtime.
 		///
 		/// Either calling `Core_version` or decoding `RuntimeVersion` failed.
@@ -478,18 +499,11 @@ decl_module! {
 				Err(Error::<T>::InvalidSpecName)?
 			}
 
-			if new_version.spec_version < current_version.spec_version {
-				Err(Error::<T>::SpecVersionNotAllowedToDecrease)?
-			} else if new_version.spec_version == current_version.spec_version {
-				if new_version.impl_version < current_version.impl_version {
-					Err(Error::<T>::ImplVersionNotAllowedToDecrease)?
-				} else if new_version.impl_version == current_version.impl_version {
-					Err(Error::<T>::SpecOrImplVersionNeedToIncrease)?
-				}
+			if new_version.spec_version <= current_version.spec_version {
+				Err(Error::<T>::SpecVersionNeedsToIncrease)?
 			}
 
 			storage::unhashed::put_raw(well_known_keys::CODE, &code);
-			RuntimeUpgraded::put(true);
 			Self::deposit_event(RawEvent::CodeUpdated);
 		}
 
@@ -498,7 +512,6 @@ decl_module! {
 		pub fn set_code_without_checks(origin, code: Vec<u8>) {
 			ensure_root(origin)?;
 			storage::unhashed::put_raw(well_known_keys::CODE, &code);
-			RuntimeUpgraded::put(true);
 			Self::deposit_event(RawEvent::CodeUpdated);
 		}
 
@@ -526,9 +539,6 @@ decl_module! {
 			ensure_root(origin)?;
 			for i in &items {
 				storage::unhashed::put_raw(&i.0, &i.1);
-				if i.0 == well_known_keys::CODE {
-					RuntimeUpgraded::put(true);
-				}
 			}
 		}
 
@@ -558,6 +568,13 @@ decl_module! {
 			ensure!(account.data == T::AccountData::default(), Error::<T>::NonDefaultComposite);
 			Account::<T>::remove(who);
 		}
+
+		fn on_runtime_upgrade() {
+			// Remove the old `RuntimeUpgraded` storage entry.
+			let mut runtime_upgraded_key = sp_io::hashing::twox_128(b"System").to_vec();
+			runtime_upgraded_key.extend(&sp_io::hashing::twox_128(b"RuntimeUpgraded"));
+			sp_io::storage::clear(&runtime_upgraded_key);
+		}
 	}
 }
 
@@ -1935,12 +1952,12 @@ mod tests {
 		}
 
 		let test_data = vec![
-			("test", 1, 2, Ok(())),
-			("test", 1, 1, Err(Error::<Test>::SpecOrImplVersionNeedToIncrease)),
+			("test", 1, 2, Err(Error::<Test>::SpecVersionNeedsToIncrease)),
+			("test", 1, 1, Err(Error::<Test>::SpecVersionNeedsToIncrease)),
 			("test2", 1, 1, Err(Error::<Test>::InvalidSpecName)),
 			("test", 2, 1, Ok(())),
-			("test", 0, 1, Err(Error::<Test>::SpecVersionNotAllowedToDecrease)),
-			("test", 1, 0, Err(Error::<Test>::ImplVersionNotAllowedToDecrease)),
+			("test", 0, 1, Err(Error::<Test>::SpecVersionNeedsToIncrease)),
+			("test", 1, 0, Err(Error::<Test>::SpecVersionNeedsToIncrease)),
 		];
 
 		for (spec_name, spec_version, impl_version, expected) in test_data.into_iter() {
@@ -1980,8 +1997,6 @@ mod tests {
 				System::events(),
 				vec![EventRecord { phase: Phase::ApplyExtrinsic(0), event: 102u16, topics: vec![] }],
 			);
-
-			assert_eq!(RuntimeUpgraded::get(), true);
 		});
 	}
 
@@ -1998,8 +2013,6 @@ mod tests {
 					substrate_test_runtime_client::runtime::WASM_BINARY.to_vec()
 				)],
 			).unwrap();
-
-			assert_eq!(RuntimeUpgraded::get(), true);
 		});
 	}
 }