pezkuwichain/pezkuwi-subxt
1
0
Fork 0
mirror of https://github.com/pezkuwichain/pezkuwi-subxt.git synced 2026-06-24 21:51:08 +00:00
Code Issues Packages Projects Releases Wiki Activity

[frame] #[pallet::composite_enum] improved variant count handling + removed pallet_balances's MaxHolds config (#2657)

Browse Source 
I started this investigation/issue based on @liamaharon question
[here](https://github.com/paritytech/polkadot-sdk/pull/1801#discussion_r1410452499).

## Problem

The `pallet_balances` integrity test should correctly detect that the
runtime has correct distinct `HoldReasons` variant count. I assume the
same situation exists for RuntimeFreezeReason.

It is not a critical problem, if we set `MaxHolds` with a sufficiently
large value, everything should be ok. However, in this case, the
integrity_test check becomes less useful.

**Situation for "any" runtime:**
- `HoldReason` enums from different pallets:
```rust
        /// from pallet_nis
        #[pallet::composite_enum]
	pub enum HoldReason {
		NftReceipt,
	}

        /// from pallet_preimage
        #[pallet::composite_enum]
	pub enum HoldReason {
		Preimage,
	}

        // from pallet_state-trie-migration
        #[pallet::composite_enum]
	pub enum HoldReason {
		SlashForContinueMigrate,
		SlashForMigrateCustomTop,
		SlashForMigrateCustomChild,
	}
```

- generated `RuntimeHoldReason` enum looks like:
```rust
pub enum RuntimeHoldReason {

    #[codec(index = 32u8)]
    Preimage(pallet_preimage::HoldReason),

    #[codec(index = 38u8)]
    Nis(pallet_nis::HoldReason),

    #[codec(index = 42u8)]
    StateTrieMigration(pallet_state_trie_migration::HoldReason),
}
```

- composite enum `RuntimeHoldReason` variant count is detected as `3`
- we set `type MaxHolds = ConstU32<3>`
- `pallet_balances::integrity_test` is ok with `3`(at least 3)

However, the real problem can occur in a live runtime where some
functionality might stop working. This is due to a total of 5 distinct
hold reasons (for pallets with multi-instance support, it is even more),
and not all of them can be used because of an incorrect `MaxHolds`,
which is deemed acceptable according to the `integrity_test`:
  ```
  // pseudo-code - if we try to call all of these:

T::Currency::hold(&pallet_nis::HoldReason::NftReceipt.into(),
&nft_owner, deposit)?;
T::Currency::hold(&pallet_preimage::HoldReason::Preimage.into(),
&nft_owner, deposit)?;

T::Currency::hold(&pallet_state_trie_migration::HoldReason::SlashForContinueMigrate.into(),
&nft_owner, deposit)?;

  // With `type MaxHolds = ConstU32<3>` these two will fail

T::Currency::hold(&pallet_state_trie_migration::HoldReason::SlashForMigrateCustomTop.into(),
&nft_owner, deposit)?;

T::Currency::hold(&pallet_state_trie_migration::HoldReason::SlashForMigrateCustomChild.into(),
&nft_owner, deposit)?;
  ```  


## Solutions

A macro `#[pallet::*]` expansion is extended of `VariantCount`
implementation for the `#[pallet::composite_enum]` enum type. This
expansion generates the `VariantCount` implementation for pallets'
`HoldReason`, `FreezeReason`, `LockId`, and `SlashReason`. Enum variants
must be plain enum values without fields to ensure a deterministic
count.

The composite runtime enum, `RuntimeHoldReason` and
`RuntimeFreezeReason`, now sets `VariantCount::VARIANT_COUNT` as the sum
of pallets' enum `VariantCount::VARIANT_COUNT`:
```rust
#[frame_support::pallet(dev_mode)]
mod module_single_instance {

	#[pallet::composite_enum]
	pub enum HoldReason {
		ModuleSingleInstanceReason1,
		ModuleSingleInstanceReason2,
	}
...
}

#[frame_support::pallet(dev_mode)]
mod module_multi_instance {

	#[pallet::composite_enum]
	pub enum HoldReason<I: 'static = ()> {
		ModuleMultiInstanceReason1,
		ModuleMultiInstanceReason2,
		ModuleMultiInstanceReason3,
	}
...
}


impl self::sp_api_hidden_includes_construct_runtime::hidden_include::traits::VariantCount
    for RuntimeHoldReason
{
    const VARIANT_COUNT: u32 = 0
        + module_single_instance::HoldReason::VARIANT_COUNT
        + module_multi_instance::HoldReason::<module_multi_instance::Instance1>::VARIANT_COUNT
        + module_multi_instance::HoldReason::<module_multi_instance::Instance2>::VARIANT_COUNT
        + module_multi_instance::HoldReason::<module_multi_instance::Instance3>::VARIANT_COUNT;
}
```

In addition, `MaxHolds` is removed (as suggested
[here](https://github.com/paritytech/polkadot-sdk/pull/2657#discussion_r1443324573))
from `pallet_balances`, and its `Holds` are now bounded to
`RuntimeHoldReason::VARIANT_COUNT`. Therefore, there is no need to let
the runtime specify `MaxHolds`.


## For reviewers

Relevant changes can be found here:
- `substrate/frame/support/procedural/src/lib.rs` 
-  `substrate/frame/support/procedural/src/pallet/parse/composite.rs`
-  `substrate/frame/support/procedural/src/pallet/expand/composite.rs`
-
`substrate/frame/support/procedural/src/construct_runtime/expand/composite_helper.rs`
-
`substrate/frame/support/procedural/src/construct_runtime/expand/hold_reason.rs`
-
`substrate/frame/support/procedural/src/construct_runtime/expand/freeze_reason.rs`
- `substrate/frame/support/src/traits/misc.rs`

And the rest of the files is just about removed `MaxHolds` from
`pallet_balances`

## Next steps

Do the same for `MaxFreezes`
https://github.com/paritytech/polkadot-sdk/issues/2997.

---------

Co-authored-by: command-bot <>
Co-authored-by: Bastian Köcher <git@kchr.de>
Co-authored-by: Dónal Murray <donal.murray@parity.io>
Co-authored-by: gupnik <nikhilgupta.iitk@gmail.com>
This commit is contained in:
Branislav Kontur
2024-01-31 07:19:16 +01:00
committed by GitHub
parent cc4805b51e
commit bb8ddc46c1
118 changed files with 610 additions and 315 deletions
Download Patch File Download Diff File Expand all files Collapse all files
substrate/frame/support/procedural/src/construct_runtime/expand/composite_helper.rs
+31
View File
@@ -68,3 +68,34 @@ pub(crate) fn expand_variant(
}
}
}
pub(crate) fn expand_variant_count(
composite_name: &str,
path: &PalletPath,
instance: Option<&Ident>,
) -> TokenStream {
let composite_name = quote::format_ident!("{}", composite_name);
if let Some(inst) = instance {
quote! {
#path::#composite_name::<#path::#inst>::VARIANT_COUNT
}
} else {
// Wrapped `<`..`>` means: use default type parameter for enum.
//
// This is used for pallets without instance support or pallets with instance support when
// we don't specify instance:
//
// ```nocompile
// pub struct Pallet<T, I = ()>{..}
//
// #[pallet::composite_enum]
// pub enum HoldReason<I: 'static = ()> {..}
//
// Pallet1: pallet_x, // <- default type parameter
// ```
quote! {
<#path::#composite_name>::VARIANT_COUNT
}
}
}
substrate/frame/support/procedural/src/construct_runtime/expand/freeze_reason.rs
+8 -2
View File
@@ -23,6 +23,7 @@ use quote::quote;
pub fn expand_outer_freeze_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -> TokenStream {
let mut conversion_fns = Vec::new();
let mut freeze_reason_variants = Vec::new();
let mut freeze_reason_variants_count = Vec::new();
for decl in pallet_decls {
if let Some(_) = decl.find_part("FreezeReason") {
let variant_name = &decl.name;
@@ -44,9 +45,14 @@ pub fn expand_outer_freeze_reason(pallet_decls: &[Pallet], scrate: &TokenStream)
instance,
variant_name,
));
freeze_reason_variants_count.push(composite_helper::expand_variant_count(
"FreezeReason",
path,
instance,
));
}
}
let freeze_reason_variants_count = freeze_reason_variants.len() as u32;
quote! {
/// A reason for placing a freeze on funds.
@@ -61,7 +67,7 @@ pub fn expand_outer_freeze_reason(pallet_decls: &[Pallet], scrate: &TokenStream)
}
impl #scrate::traits::VariantCount for RuntimeFreezeReason {
const VARIANT_COUNT: u32 = #freeze_reason_variants_count;
const VARIANT_COUNT: u32 = 0 #( + #freeze_reason_variants_count )*;
}
#( #conversion_fns )*
substrate/frame/support/procedural/src/construct_runtime/expand/hold_reason.rs
+8 -2
View File
@@ -23,6 +23,7 @@ use quote::quote;
pub fn expand_outer_hold_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -> TokenStream {
let mut conversion_fns = Vec::new();
let mut hold_reason_variants = Vec::new();
let mut hold_reason_variants_count = Vec::new();
for decl in pallet_decls {
if let Some(_) = decl.find_part("HoldReason") {
let variant_name = &decl.name;
@@ -44,9 +45,14 @@ pub fn expand_outer_hold_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -
instance,
variant_name,
));
hold_reason_variants_count.push(composite_helper::expand_variant_count(
"HoldReason",
path,
instance,
));
}
}
let hold_reason_variants_count = hold_reason_variants.len() as u32;
quote! {
/// A reason for placing a hold on funds.
@@ -61,7 +67,7 @@ pub fn expand_outer_hold_reason(pallet_decls: &[Pallet], scrate: &TokenStream) -
}
impl #scrate::traits::VariantCount for RuntimeHoldReason {
const VARIANT_COUNT: u32 = #hold_reason_variants_count;
const VARIANT_COUNT: u32 = 0 #( + #hold_reason_variants_count )*;
}
#( #conversion_fns )*