Switch to new proc-macro crate for implementing traits for tuples (#3598)

* Switch to new proc-macro crate for implementing traits for tuples

* Switch back to stable `Cargo.lock` format

* Reduce tuple number to match rusts default implementation

substrate/srml/authorship/Cargo.toml

@@ -14,6 +14,7 @@ sr-primitives = { path = "../../core/sr-primitives", default-features = false }
 support = { package = "srml-support", path = "../support", default-features = false }
 system = { package = "srml-system", path = "../system", default-features = false }
 runtime-io ={ package = "sr-io", path = "../../core/sr-io", default-features = false }
+impl-trait-for-tuples = "0.1"
 
 [features]
 default = ["std"]

substrate/srml/authorship/src/lib.rs

@@ -22,7 +22,7 @@
 
 use rstd::{result, prelude::*};
 use rstd::collections::btree_set::BTreeSet;
-use support::{decl_module, decl_storage, for_each_tuple, StorageValue};
+use support::{decl_module, decl_storage, StorageValue};
 use support::traits::{FindAuthor, VerifySeal, Get};
 use support::dispatch::Result as DispatchResult;
 use codec::{Encode, Decode};
@@ -112,6 +112,7 @@ pub trait Trait: system::Trait {
 
 /// An event handler for the authorship module. There is a dummy implementation
 /// for `()`, which does nothing.
+#[impl_trait_for_tuples::impl_for_tuples(30)]
 pub trait EventHandler<Author, BlockNumber> {
 	/// Note that the given account ID is the author of the current block.
 	fn note_author(author: Author);
@@ -121,30 +122,6 @@ pub trait EventHandler<Author, BlockNumber> {
 	fn note_uncle(author: Author, age: BlockNumber);
 }
 
-macro_rules! impl_event_handler {
-	() => (
-		impl<A, B> EventHandler<A, B> for () {
-			fn note_author(_author: A) { }
-			fn note_uncle(_author: A, _age: B) { }
-		}
-	);
-
-	( $($t:ident)* ) => {
-		impl<Author: Clone, BlockNumber: Clone, $($t: EventHandler<Author, BlockNumber>),*>
-			EventHandler<Author, BlockNumber> for ($($t,)*)
-		{
-			fn note_author(author: Author) {
-				$($t::note_author(author.clone());)*
-			}
-			fn note_uncle(author: Author, age: BlockNumber) {
-				$($t::note_uncle(author.clone(), age.clone());)*
-			}
-		}
-	}
-}
-
-for_each_tuple!(impl_event_handler);
-
 /// Additional filtering on uncles that pass preliminary ancestry checks.
 ///
 /// This should do work such as checking seals

substrate/srml/finality-tracker/Cargo.toml

@@ -12,6 +12,7 @@ rstd = { package = "sr-std", path = "../../core/sr-std", default-features = fals
 sr-primitives = { path = "../../core/sr-primitives", default-features = false }
 support = { package = "srml-support", path = "../support", default-features = false }
 srml-system = { path = "../system", default-features = false }
+impl-trait-for-tuples = "0.1"
 
 [dev-dependencies]
 primitives = { package = "substrate-primitives",  path = "../../core/primitives", default-features = false }

substrate/srml/finality-tracker/src/lib.rs

@@ -26,7 +26,7 @@ use support::StorageValue;
 use sr_primitives::traits::{One, Zero, SaturatedConversion};
 use rstd::{prelude::*, result, cmp, vec};
 use codec::Decode;
-use support::{decl_module, decl_storage, for_each_tuple};
+use support::{decl_module, decl_storage};
 use support::traits::Get;
 use srml_system::{ensure_none, Trait as SystemTrait};
 
@@ -214,30 +214,13 @@ impl<T: Trait> Module<T> {
 }
 
 /// Called when finalization stalled at a given number.
+#[impl_trait_for_tuples::impl_for_tuples(30)]
 pub trait OnFinalizationStalled<N> {
 	/// The parameter here is how many more blocks to wait before applying
 	/// changes triggered by finality stalling.
 	fn on_stalled(further_wait: N, median: N);
 }
 
-macro_rules! impl_on_stalled {
-	() => (
-		impl<N> OnFinalizationStalled<N> for () {
-			fn on_stalled(_: N, _: N) {}
-		}
-	);
-
-	( $($t:ident)* ) => {
-		impl<NUM: Clone, $($t: OnFinalizationStalled<NUM>),*> OnFinalizationStalled<NUM> for ($($t,)*) {
-			fn on_stalled(further_wait: NUM, median: NUM) {
-				$($t::on_stalled(further_wait.clone(), median.clone());)*
-			}
-		}
-	}
-}
-
-for_each_tuple!(impl_on_stalled);
-
 impl<T: Trait> ProvideInherent for Module<T> {
 	type Call = Call<T>;
 	type Error = MakeFatalError<()>;

substrate/srml/session/Cargo.toml

@@ -16,6 +16,7 @@ system = { package = "srml-system", path = "../system", default-features = false
 timestamp = { package = "srml-timestamp", path = "../timestamp", default-features = false }
 substrate-trie = { path = "../../core/trie", default-features = false, optional = true }
 runtime-io ={ package = "sr-io", path = "../../core/sr-io", default-features = false }
+impl-trait-for-tuples = "0.1"
 
 [dev-dependencies]
 primitives = { package = "substrate-primitives",  path = "../../core/primitives" }

substrate/srml/session/src/lib.rs

@@ -126,8 +126,8 @@ use sr_primitives::weights::SimpleDispatchInfo;
 use sr_primitives::traits::{Convert, Zero, Member, OpaqueKeys};
 use sr_staking_primitives::SessionIndex;
 use support::{
-	dispatch::Result, ConsensusEngineId, StorageValue, StorageDoubleMap, for_each_tuple,
-	decl_module, decl_event, decl_storage,
+	dispatch::Result, ConsensusEngineId, StorageValue, StorageDoubleMap, decl_module, decl_event,
+	decl_storage,
 };
 use support::{ensure, traits::{OnFreeBalanceZero, Get, FindAuthor}, Parameter};
 use system::{self, ensure_signed};
@@ -251,63 +251,52 @@ pub trait OneSessionHandler<ValidatorId> {
 
 	/// A validator got disabled. Act accordingly until a new session begins.
 	fn on_disabled(_validator_index: usize);
-
 }
 
-macro_rules! impl_session_handlers {
-	() => (
-		impl<AId> SessionHandler<AId> for () {
-			fn on_genesis_session<Ks: OpaqueKeys>(_: &[(AId, Ks)]) {}
-			fn on_new_session<Ks: OpaqueKeys>(_: bool, _: &[(AId, Ks)], _: &[(AId, Ks)]) {}
-			fn on_before_session_ending() {}
-			fn on_disabled(_: usize) {}
-		}
-	);
+#[impl_trait_for_tuples::impl_for_tuples(30)]
+#[tuple_types_no_default_trait_bound]
+impl<AId> SessionHandler<AId> for Tuple {
+	for_tuples!( where #( Tuple: OneSessionHandler<AId> )* );
 
-	( $($t:ident)* ) => {
-		impl<AId, $( $t: OneSessionHandler<AId> ),*> SessionHandler<AId> for ( $( $t , )* ) {
-			fn on_genesis_session<Ks: OpaqueKeys>(validators: &[(AId, Ks)]) {
-				$(
-					let our_keys: Box<dyn Iterator<Item=_>> = Box::new(validators.iter()
-						.map(|k| (&k.0, k.1.get::<$t::Key>(<$t::Key as AppKey>::ID)
-							.unwrap_or_default())));
+	fn on_genesis_session<Ks: OpaqueKeys>(validators: &[(AId, Ks)]) {
+		for_tuples!(
+			#(
+				let our_keys: Box<dyn Iterator<Item=_>> = Box::new(validators.iter()
+					.map(|k| (&k.0, k.1.get::<Tuple::Key>(<Tuple::Key as AppKey>::ID)
+						.unwrap_or_default())));
 
-					$t::on_genesis_session(our_keys);
-				)*
-			}
-			fn on_new_session<Ks: OpaqueKeys>(
-				changed: bool,
-				validators: &[(AId, Ks)],
-				queued_validators: &[(AId, Ks)],
-			) {
-				$(
-					let our_keys: Box<dyn Iterator<Item=_>> = Box::new(validators.iter()
-						.map(|k| (&k.0, k.1.get::<$t::Key>(<$t::Key as AppKey>::ID)
-							.unwrap_or_default())));
-					let queued_keys: Box<dyn Iterator<Item=_>> = Box::new(queued_validators.iter()
-						.map(|k| (&k.0, k.1.get::<$t::Key>(<$t::Key as AppKey>::ID)
-							.unwrap_or_default())));
-					$t::on_new_session(changed, our_keys, queued_keys);
-				)*
-			}
+				Tuple::on_genesis_session(our_keys);
+			)*
+		)
+	}
 
-			fn on_before_session_ending() {
-				$(
-					$t::on_before_session_ending();
-				)*
-			}
+	fn on_new_session<Ks: OpaqueKeys>(
+		changed: bool,
+		validators: &[(AId, Ks)],
+		queued_validators: &[(AId, Ks)],
+	) {
+		for_tuples!(
+			#(
+				let our_keys: Box<dyn Iterator<Item=_>> = Box::new(validators.iter()
+					.map(|k| (&k.0, k.1.get::<Tuple::Key>(<Tuple::Key as AppKey>::ID)
+						.unwrap_or_default())));
+				let queued_keys: Box<dyn Iterator<Item=_>> = Box::new(queued_validators.iter()
+					.map(|k| (&k.0, k.1.get::<Tuple::Key>(<Tuple::Key as AppKey>::ID)
+						.unwrap_or_default())));
+				Tuple::on_new_session(changed, our_keys, queued_keys);
+			)*
+		)
+	}
 
-			fn on_disabled(i: usize) {
-				$(
-					$t::on_disabled(i);
-				)*
-			}
-		}
+	fn on_before_session_ending() {
+		for_tuples!( #( Tuple::on_before_session_ending(); )* )
+	}
+
+	fn on_disabled(i: usize) {
+		for_tuples!( #( Tuple::on_disabled(i); )* )
 	}
 }
 
-for_each_tuple!(impl_session_handlers);
-
 /// Handler for selecting the genesis validator set.
 pub trait SelectInitialValidators<ValidatorId> {
 	/// Returns the initial validator set. If `None` is returned

substrate/srml/support/Cargo.toml

@@ -17,6 +17,7 @@ srml-support-procedural = { package = "srml-support-procedural", path = "./proce
 paste = "0.1"
 once_cell = { version = "0.1.6", default-features = false, optional = true }
 bitmask = { version = "0.5", default-features = false }
+impl-trait-for-tuples = "0.1"
 
 [dev-dependencies]
 pretty_assertions = "0.6.1"

substrate/srml/support/src/lib.rs

@@ -266,21 +266,6 @@ pub enum Void {}
 #[doc(hidden)]
 pub use serde::{Serialize, Deserialize};
 
-/// Programatically create derivations for tuples of up to 19 elements. You provide a second macro
-/// which is called once per tuple size, along with a number of identifiers, one for each element
-/// of the tuple.
-#[macro_export]
-macro_rules! for_each_tuple {
-	($m:ident) => {
-		for_each_tuple! { @IMPL $m !! A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, }
-	};
-	(@IMPL $m:ident !!) => { $m! { } };
-	(@IMPL $m:ident !! $h:ident, $($t:ident,)*) => {
-		$m! { $h $($t)* }
-		for_each_tuple! { @IMPL $m !! $($t,)* }
-	}
-}
-
 #[cfg(test)]
 mod tests {
 	use super::*;

substrate/srml/support/src/traits.rs

@@ -24,8 +24,6 @@ use primitives::u32_trait::Value as U32;
 use crate::sr_primitives::traits::{MaybeSerializeDebug, SimpleArithmetic, Saturating};
 use crate::sr_primitives::ConsensusEngineId;
 
-use super::for_each_tuple;
-
 /// Anything that can have a `::len()` method.
 pub trait Len {
 	/// Return the length of data type.
@@ -63,29 +61,12 @@ impl<V: PartialEq, T: Get<V>> Contains<V> for T {
 }
 
 /// The account with the given id was killed.
+#[impl_trait_for_tuples::impl_for_tuples(30)]
 pub trait OnFreeBalanceZero<AccountId> {
 	/// The account was the given id was killed.
 	fn on_free_balance_zero(who: &AccountId);
 }
 
-macro_rules! impl_on_free_balance_zero {
-	() => (
-		impl<AccountId> OnFreeBalanceZero<AccountId> for () {
-			fn on_free_balance_zero(_: &AccountId) {}
-		}
-	);
-
-	( $($t:ident)* ) => {
-		impl<AccountId, $($t: OnFreeBalanceZero<AccountId>),*> OnFreeBalanceZero<AccountId> for ($($t,)*) {
-			fn on_free_balance_zero(who: &AccountId) {
-				$($t::on_free_balance_zero(who);)*
-			}
-		}
-	}
-}
-
-for_each_tuple!(impl_on_free_balance_zero);
-
 /// Trait for a hook to get called when some balance has been minted, causing dilution.
 pub trait OnDilution<Balance> {
 	/// Some `portion` of the total balance just "grew" by `minted`. `portion` is the pre-growth

substrate/srml/system/Cargo.toml

@@ -14,6 +14,7 @@ runtime-io ={ package = "sr-io", path = "../../core/sr-io", default-features = f
 sr-primitives = { path = "../../core/sr-primitives", default-features = false }
 sr-version = { path = "../../core/sr-version", default-features = false }
 support = { package = "srml-support", path = "../support", default-features = false }
+impl-trait-for-tuples = "0.1"
 
 [dev-dependencies]
 criterion = "0.2"

substrate/srml/system/src/lib.rs

@@ -112,7 +112,7 @@ use sr_primitives::{
 use primitives::storage::well_known_keys;
 use support::{
 	storage, decl_module, decl_event, decl_storage, StorageDoubleMap, StorageValue, StorageMap,
-	Parameter, for_each_tuple, traits::{Contains, Get}, decl_error,
+	Parameter, traits::{Contains, Get}, decl_error,
 };
 use safe_mix::TripletMix;
 use codec::{Encode, Decode};
@@ -126,29 +126,12 @@ use primitives::ChangesTrieConfiguration;
 pub mod offchain;
 
 /// Handler for when a new account has been created.
+#[impl_trait_for_tuples::impl_for_tuples(30)]
 pub trait OnNewAccount<AccountId> {
 	/// A new account `who` has been registered.
 	fn on_new_account(who: &AccountId);
 }
 
-macro_rules! impl_on_new_account {
-	() => (
-		impl<AccountId> OnNewAccount<AccountId> for () {
-			fn on_new_account(_: &AccountId) {}
-		}
-	);
-
-	( $($t:ident)* ) => {
-		impl<AccountId, $($t: OnNewAccount<AccountId>),*> OnNewAccount<AccountId> for ($($t,)*) {
-			fn on_new_account(who: &AccountId) {
-				$($t::on_new_account(who);)*
-			}
-		}
-	}
-}
-
-for_each_tuple!(impl_on_new_account);
-
 /// Determiner to say whether a given account is unused.
 pub trait IsDeadAccount<AccountId> {
 	/// Is the given account dead?

substrate/srml/timestamp/Cargo.toml

@@ -12,6 +12,7 @@ sr-primitives = { path = "../../core/sr-primitives", default-features = false }
 inherents = { package = "substrate-inherents", path = "../../core/inherents", default-features = false }
 support = { package = "srml-support", path = "../support", default-features = false }
 system = { package = "srml-system", path = "../system", default-features = false }
+impl-trait-for-tuples = "0.1"
 
 [dev-dependencies]
 runtime-io ={ package = "sr-io", path = "../../core/sr-io" }

substrate/srml/timestamp/src/lib.rs

@@ -96,7 +96,7 @@ use codec::Encode;
 use codec::Decode;
 #[cfg(feature = "std")]
 use inherents::ProvideInherentData;
-use support::{StorageValue, Parameter, decl_storage, decl_module, for_each_tuple};
+use support::{StorageValue, Parameter, decl_storage, decl_module};
 use support::traits::{Time, Get};
 use sr_primitives::traits::{
 	SimpleArithmetic, Zero, SaturatedConversion, Scale
@@ -183,28 +183,11 @@ impl ProvideInherentData for InherentDataProvider {
 }
 
 /// A trait which is called when the timestamp is set.
+#[impl_trait_for_tuples::impl_for_tuples(30)]
 pub trait OnTimestampSet<Moment> {
 	fn on_timestamp_set(moment: Moment);
 }
 
-macro_rules! impl_timestamp_set {
-	() => (
-		impl<Moment> OnTimestampSet<Moment> for () {
-			fn on_timestamp_set(_: Moment) {}
-		}
-	);
-
-	( $($t:ident)* ) => {
-		impl<Moment: Copy, $($t: OnTimestampSet<Moment>),*> OnTimestampSet<Moment> for ($($t,)*) {
-			fn on_timestamp_set(moment: Moment) {
-				$($t::on_timestamp_set(moment);)*
-			}
-		}
-	}
-}
-
-for_each_tuple!(impl_timestamp_set);
-
 /// The module configuration trait
 pub trait Trait: system::Trait {
 	/// Type used for expressing timestamp.