Adds instance support for composite enums (paritytech#1857)

Fixes paritytech#1839

Currently, `composite_enum`s do not support pallet instances. This PR
allows the following:
```rust
	#[pallet::composite_enum]
	pub enum HoldReason<I: 'static = ()> {
		SomeHoldReason
	}
```

### Todo

- [x]  UI Test

substrate/frame/balances/src/lib.rs

@@ -256,7 +256,7 @@ pub mod pallet {
 
  /// The overarching hold reason.
  #[pallet::no_default_bounds]
- type RuntimeHoldReason: Parameter + Member + MaxEncodedLen + Ord + Copy;
+ type RuntimeHoldReason: Parameter + Member + MaxEncodedLen + Copy;
 
  /// Weight information for extrinsics in this pallet.
  type WeightInfo: WeightInfo;
@@ -300,7 +300,7 @@ pub mod pallet {
  type ReserveIdentifier: Parameter + Member + MaxEncodedLen + Ord + Copy;
 
  /// The ID type for freezes.
- type FreezeIdentifier: Parameter + Member + MaxEncodedLen + Ord + Copy;
+ type FreezeIdentifier: Parameter + Member + MaxEncodedLen + Copy;
 
  /// The maximum number of locks that should exist on an account.
  /// Not strictly enforced, but used for weight estimation.

substrate/frame/support/procedural/src/construct_runtime/expand/composite_helper.rs

@@ -0,0 +1,70 @@
+// This file is part of Substrate.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License
+
+use crate::construct_runtime::parse::PalletPath;
+use proc_macro2::{Ident, TokenStream};
+use quote::quote;
+
+pub(crate) fn expand_conversion_fn(
+ composite_name: &str,
+ path: &PalletPath,
+ instance: Option<&Ident>,
+ variant_name: &Ident,
+) -> TokenStream {
+ let composite_name = quote::format_ident!("{}", composite_name);
+ let runtime_composite_name = quote::format_ident!("Runtime{}", composite_name);
+
+ if let Some(inst) = instance {
+ quote! {
+ impl From<#path::#composite_name<#path::#inst>> for #runtime_composite_name {
+ fn from(hr: #path::#composite_name<#path::#inst>) -> Self {
+ #runtime_composite_name::#variant_name(hr)
+ }
+ }
+ }
+ } else {
+ quote! {
+ impl From<#path::#composite_name> for #runtime_composite_name {
+ fn from(hr: #path::#composite_name) -> Self {
+ #runtime_composite_name::#variant_name(hr)
+ }
+ }
+ }
+ }
+}
+
+pub(crate) fn expand_variant(
+ composite_name: &str,
+ index: u8,
+ path: &PalletPath,
+ instance: Option<&Ident>,
+ variant_name: &Ident,
+) -> TokenStream {
+ let composite_name = quote::format_ident!("{}", composite_name);
+
+ if let Some(inst) = instance {
+ quote! {
+ #[codec(index = #index)]
+ #variant_name(#path::#composite_name<#path::#inst>),
+ }
+ } else {
+ quote! {
+ #[codec(index = #index)]
+ #variant_name(#path::#composite_name),
+ }
+ }
+}

substrate/frame/support/procedural/src/construct_runtime/expand/freeze_reason.rs

@@ -15,8 +15,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License
 
-use crate::construct_runtime::{parse::PalletPath, Pallet};
-use proc_macro2::{Ident, TokenStream};
+use super::composite_helper;
+use crate::construct_runtime::Pallet;
+use proc_macro2::TokenStream;
 use quote::quote;
 
 pub fn expand_outer_freeze_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -> TokenStream {
@@ -27,17 +28,29 @@ pub fn expand_outer_freeze_reason(pallet_decls: &[Pallet], scrate: &TokenStream)
  let variant_name = &decl.name;
  let path = &decl.path;
  let index = decl.index;
+ let instance = decl.instance.as_ref();
 
- conversion_fns.push(expand_conversion_fn(path, variant_name));
+ conversion_fns.push(composite_helper::expand_conversion_fn(
+ "FreezeReason",
+ path,
+ instance,
+ variant_name,
+ ));
 
- freeze_reason_variants.push(expand_variant(index, path, variant_name));
+ freeze_reason_variants.push(composite_helper::expand_variant(
+ "FreezeReason",
+ index,
+ path,
+ instance,
+ variant_name,
+ ));
  }
  }
 
  quote! {
  /// A reason for placing a freeze on funds.
  #[derive(
- Copy, Clone, Eq, PartialEq, Ord, PartialOrd,
+ Copy, Clone, Eq, PartialEq,
  #scrate::__private::codec::Encode, #scrate::__private::codec::Decode, #scrate::__private::codec::MaxEncodedLen,
  #scrate::__private::scale_info::TypeInfo,
  #scrate::__private::RuntimeDebug,
@@ -49,20 +62,3 @@ pub fn expand_outer_freeze_reason(pallet_decls: &[Pallet], scrate: &TokenStream)
  #( #conversion_fns )*
  }
 }
-
-fn expand_conversion_fn(path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- impl From<#path::FreezeReason> for RuntimeFreezeReason {
- fn from(hr: #path::FreezeReason) -> Self {
- RuntimeFreezeReason::#variant_name(hr)
- }
- }
- }
-}
-
-fn expand_variant(index: u8, path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- #[codec(index = #index)]
- #variant_name(#path::FreezeReason),
- }
-}

substrate/frame/support/procedural/src/construct_runtime/expand/hold_reason.rs

@@ -15,8 +15,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License
 
-use crate::construct_runtime::{parse::PalletPath, Pallet};
-use proc_macro2::{Ident, TokenStream};
+use super::composite_helper;
+use crate::construct_runtime::Pallet;
+use proc_macro2::TokenStream;
 use quote::quote;
 
 pub fn expand_outer_hold_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -> TokenStream {
@@ -27,17 +28,29 @@ pub fn expand_outer_hold_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -
  let variant_name = &decl.name;
  let path = &decl.path;
  let index = decl.index;
+ let instance = decl.instance.as_ref();
 
- conversion_fns.push(expand_conversion_fn(path, variant_name));
+ conversion_fns.push(composite_helper::expand_conversion_fn(
+ "HoldReason",
+ path,
+ instance,
+ variant_name,
+ ));
 
- hold_reason_variants.push(expand_variant(index, path, variant_name));
+ hold_reason_variants.push(composite_helper::expand_variant(
+ "HoldReason",
+ index,
+ path,
+ instance,
+ variant_name,
+ ));
  }
  }
 
  quote! {
  /// A reason for placing a hold on funds.
  #[derive(
- Copy, Clone, Eq, PartialEq, Ord, PartialOrd,
+ Copy, Clone, Eq, PartialEq,
  #scrate::__private::codec::Encode, #scrate::__private::codec::Decode, #scrate::__private::codec::MaxEncodedLen,
  #scrate::__private::scale_info::TypeInfo,
  #scrate::__private::RuntimeDebug,
@@ -49,20 +62,3 @@ pub fn expand_outer_hold_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -
  #( #conversion_fns )*
  }
 }
-
-fn expand_conversion_fn(path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- impl From<#path::HoldReason> for RuntimeHoldReason {
- fn from(hr: #path::HoldReason) -> Self {
- RuntimeHoldReason::#variant_name(hr)
- }
- }
- }
-}
-
-fn expand_variant(index: u8, path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- #[codec(index = #index)]
- #variant_name(#path::HoldReason),
- }
-}

substrate/frame/support/procedural/src/construct_runtime/expand/lock_id.rs

@@ -15,8 +15,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License
 
-use crate::construct_runtime::{parse::PalletPath, Pallet};
-use proc_macro2::{Ident, TokenStream};
+use super::composite_helper;
+use crate::construct_runtime::Pallet;
+use proc_macro2::TokenStream;
 use quote::quote;
 
 pub fn expand_outer_lock_id(pallet_decls: &[Pallet], scrate: &TokenStream) -> TokenStream {
@@ -27,17 +28,29 @@ pub fn expand_outer_lock_id(pallet_decls: &[Pallet], scrate: &TokenStream) -> To
  let variant_name = &decl.name;
  let path = &decl.path;
  let index = decl.index;
+ let instance = decl.instance.as_ref();
 
- conversion_fns.push(expand_conversion_fn(path, variant_name));
+ conversion_fns.push(composite_helper::expand_conversion_fn(
+ "LockId",
+ path,
+ instance,
+ variant_name,
+ ));
 
- lock_id_variants.push(expand_variant(index, path, variant_name));
+ lock_id_variants.push(composite_helper::expand_variant(
+ "LockId",
+ index,
+ path,
+ instance,
+ variant_name,
+ ));
  }
  }
 
  quote! {
  /// An identifier for each lock placed on funds.
  #[derive(
- Copy, Clone, Eq, PartialEq, Ord, PartialOrd,
+ Copy, Clone, Eq, PartialEq,
  #scrate::__private::codec::Encode, #scrate::__private::codec::Decode, #scrate::__private::codec::MaxEncodedLen,
  #scrate::__private::scale_info::TypeInfo,
  #scrate::__private::RuntimeDebug,
@@ -49,20 +62,3 @@ pub fn expand_outer_lock_id(pallet_decls: &[Pallet], scrate: &TokenStream) -> To
  #( #conversion_fns )*
  }
 }
-
-fn expand_conversion_fn(path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- impl From<#path::LockId> for RuntimeLockId {
- fn from(hr: #path::LockId) -> Self {
- RuntimeLockId::#variant_name(hr)
- }
- }
- }
-}
-
-fn expand_variant(index: u8, path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- #[codec(index = #index)]
- #variant_name(#path::LockId),
- }
-}

substrate/frame/support/procedural/src/construct_runtime/expand/mod.rs

@@ -16,6 +16,7 @@
 // limitations under the License
 
 mod call;
+pub mod composite_helper;
 mod config;
 mod freeze_reason;
 mod hold_reason;

substrate/frame/support/procedural/src/construct_runtime/expand/slash_reason.rs

@@ -15,8 +15,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License
 
-use crate::construct_runtime::{parse::PalletPath, Pallet};
-use proc_macro2::{Ident, TokenStream};
+use super::composite_helper;
+use crate::construct_runtime::Pallet;
+use proc_macro2::TokenStream;
 use quote::quote;
 
 pub fn expand_outer_slash_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -> TokenStream {
@@ -27,17 +28,29 @@ pub fn expand_outer_slash_reason(pallet_decls: &[Pallet], scrate: &TokenStream)
  let variant_name = &decl.name;
  let path = &decl.path;
  let index = decl.index;
+ let instance = decl.instance.as_ref();
 
- conversion_fns.push(expand_conversion_fn(path, variant_name));
+ conversion_fns.push(composite_helper::expand_conversion_fn(
+ "SlashReason",
+ path,
+ instance,
+ variant_name,
+ ));
 
- slash_reason_variants.push(expand_variant(index, path, variant_name));
+ slash_reason_variants.push(composite_helper::expand_variant(
+ "SlashReason",
+ index,
+ path,
+ instance,
+ variant_name,
+ ));
  }
  }
 
  quote! {
  /// A reason for slashing funds.
  #[derive(
- Copy, Clone, Eq, PartialEq, Ord, PartialOrd,
+ Copy, Clone, Eq, PartialEq,
  #scrate::__private::codec::Encode, #scrate::__private::codec::Decode, #scrate::__private::codec::MaxEncodedLen,
  #scrate::__private::scale_info::TypeInfo,
  #scrate::__private::RuntimeDebug,
@@ -49,20 +62,3 @@ pub fn expand_outer_slash_reason(pallet_decls: &[Pallet], scrate: &TokenStream)
  #( #conversion_fns )*
  }
 }
-
-fn expand_conversion_fn(path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- impl From<#path::SlashReason> for RuntimeSlashReason {
- fn from(hr: #path::SlashReason) -> Self {
- RuntimeSlashReason::#variant_name(hr)
- }
- }
- }
-}
-
-fn expand_variant(index: u8, path: &PalletPath, variant_name: &Ident) -> TokenStream {
- quote! {
- #[codec(index = #index)]
- #variant_name(#path::SlashReason),
- }
-}