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// 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.
//! Support code for the runtime.
//!
//! ## Note on Tuple Traits
//!
//! Many of the traits defined in [`traits`] have auto-implementations on tuples as well. Usually,
//! the tuple is a function of number of pallets in the runtime. By default, the traits are
//! implemented for tuples of up to 64 items.
//
// If you have more pallets in your runtime, or for any other reason need more, enabled `tuples-96`
// or the `tuples-128` complication flag. Note that these features *will increase* the compilation
// of this crate.
#![cfg_attr(not(feature = "std"), no_std)]
/// Export ourself as `frame_support` to make tests happy.
#[doc(hidden)]
extern crate self as frame_support;
#[doc(hidden)]
extern crate alloc;
/// Private exports that are being used by macros.
///
/// The exports are not stable and should not be relied on.
#[doc(hidden)]
pub mod __private {
pub use alloc::{
boxed::Box,
rc::Rc,
vec,
vec::{IntoIter, Vec},
};
pub use codec;
pub use frame_metadata as metadata;
pub use log;
pub use paste;
pub use scale_info;
pub use serde;
pub use sp_core::{Get, OpaqueMetadata, Void};
pub use sp_crypto_hashing_proc_macro;
pub use sp_inherents;
#[cfg(feature = "std")]
pub use sp_io::TestExternalities;
pub use sp_io::{self, hashing, storage::root as storage_root};
pub use sp_metadata_ir as metadata_ir;
#[cfg(feature = "std")]
pub use sp_runtime::{bounded_btree_map, bounded_vec};
pub use sp_runtime::{
traits::Dispatchable, DispatchError, RuntimeDebug, StateVersion, TransactionOutcome,
};
#[cfg(feature = "std")]
pub use sp_state_machine::BasicExternalities;
pub use sp_std;
pub use sp_tracing;
pub use tt_call::*;
}
#[macro_use]
pub mod dispatch;
pub mod crypto;
pub mod dispatch_context;
mod hash;
pub mod inherent;
pub mod instances;
pub mod migrations;
pub mod storage;
#[cfg(test)]
mod tests;
pub mod traits;
pub mod weights;
#[doc(hidden)]
pub mod unsigned {
#[doc(hidden)]
pub use crate::sp_runtime::traits::ValidateUnsigned;
#[doc(hidden)]
pub use crate::sp_runtime::transaction_validity::{
TransactionSource, TransactionValidity, TransactionValidityError, UnknownTransaction,
};
}
#[cfg(any(feature = "std", feature = "runtime-benchmarks", feature = "try-runtime", test))]
pub use self::storage::storage_noop_guard::StorageNoopGuard;
pub use self::{
dispatch::{Callable, Parameter},
hash::{
Blake2_128, Blake2_128Concat, Blake2_256, Hashable, Identity, ReversibleStorageHasher,
StorageHasher, Twox128, Twox256, Twox64Concat,
},
storage::{
bounded_btree_map::BoundedBTreeMap,
bounded_btree_set::BoundedBTreeSet,
bounded_vec::{BoundedSlice, BoundedVec},
migration,
weak_bounded_vec::WeakBoundedVec,
IterableStorageDoubleMap, IterableStorageMap, IterableStorageNMap, StorageDoubleMap,
StorageMap, StorageNMap, StoragePrefixedMap, StorageValue,
},
};
pub use sp_runtime::{
self, print, traits::Printable, ConsensusEngineId, MAX_MODULE_ERROR_ENCODED_SIZE,
};
use codec::{Decode, Encode};
use scale_info::TypeInfo;
use sp_runtime::TypeId;
/// A unified log target for support operations.
pub const LOG_TARGET: &str = "runtime::frame-support";
/// A type that cannot be instantiated.
#[derive(Encode, Decode, Debug, PartialEq, Eq, Clone, TypeInfo)]
pub enum Never {}
/// A pallet identifier. These are per pallet and should be stored in a registry somewhere.
#[derive(Clone, Copy, Eq, PartialEq, Encode, Decode, TypeInfo)]
pub struct PalletId(pub [u8; 8]);
impl TypeId for PalletId {
const TYPE_ID: [u8; 4] = *b"modl";
}
/// Generate a [`#[pallet::storage]`](pallet_macros::storage) alias outside of a pallet.
///
/// This storage alias works similarly to the [`#[pallet::storage]`](pallet_macros::storage)
/// attribute macro. It supports [`StorageValue`](storage::types::StorageValue),
/// [`StorageMap`](storage::types::StorageMap),
/// [`StorageDoubleMap`](storage::types::StorageDoubleMap) and
/// [`StorageNMap`](storage::types::StorageNMap). The main difference to the normal
/// [`#[pallet::storage]`](pallet_macros::storage) is the flexibility around declaring the
/// storage prefix to use. The storage prefix determines where to find the value in the
/// storage. [`#[pallet::storage]`](pallet_macros::storage) uses the name of the pallet as
/// declared in [`construct_runtime!`].
///
/// The flexibility around declaring the storage prefix makes this macro very useful for
/// writing migrations etc.
///
/// # Examples
///
/// There are different ways to declare the `prefix` to use. The `prefix` type can either be
/// declared explicitly by passing it to the macro as an attribute or by letting the macro
/// guess on what the `prefix` type is. The `prefix` is always passed as the first generic
/// argument to the type declaration. When using [`#[pallet::storage]`](pallet_macros::storage)
/// this first generic argument is always `_`. Besides declaring the `prefix`, the rest of the
/// type declaration works as with [`#[pallet::storage]`](pallet_macros::storage).
///
/// 1. Use the `verbatim` prefix type. This prefix type uses the given identifier as the
/// `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", verbatim_attribute)]
///
/// 2. Use the `pallet_name` prefix type. This prefix type uses the name of the pallet as
/// configured in [`construct_runtime!`] as the `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", pallet_name_attribute)]
/// It requires that the given prefix type implements
/// [`PalletInfoAccess`](traits::PalletInfoAccess) (which is always the case for FRAME pallet
/// structs). In the example above, `Pallet<T>` is the prefix type.
///
/// 3. Use the `dynamic` prefix type. This prefix type calls [`Get::get()`](traits::Get::get)
/// to get the `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", dynamic_attribute)]
/// It requires that the given prefix type implements [`Get<'static str>`](traits::Get).
///
/// 4. Let the macro "guess" what kind of prefix type to use. This only supports verbatim or
/// pallet name. The macro uses the presence of generic arguments to the prefix type as an
/// indication that it should use the pallet name as the `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", storage_alias_guess)]
pub use frame_support_procedural::storage_alias;
pub use frame_support_procedural::derive_impl;
/// Experimental macros for defining dynamic params that can be used in pallet configs.
#[cfg(feature = "experimental")]
pub mod dynamic_params {
pub use frame_support_procedural::{
dynamic_aggregated_params_internal, dynamic_pallet_params, dynamic_params,
};
}
/// Create new implementations of the [`Get`](crate::traits::Get) trait.
///
/// The so-called parameter type can be created in four different ways:
///
/// - Using `const` to create a parameter type that provides a `const` getter. It is required that
/// the `value` is const.
///
/// - Declare the parameter type without `const` to have more freedom when creating the value.
///
/// - Using `storage` to create a storage parameter type. This type is special as it tries to load
/// the value from the storage under a fixed key. If the value could not be found in the storage,
/// the given default value will be returned. It is required that the value implements
/// [`Encode`](codec::Encode) and [`Decode`](codec::Decode). The key for looking up the value in
/// the storage is built using the following formula:
///
/// `twox_128(":" ++ NAME ++ ":")` where `NAME` is the name that is passed as type name.
///
/// - Using `static` to create a static parameter type. Its value is being provided by a static
/// variable with the equivalent name in `UPPER_SNAKE_CASE`. An additional `set` function is
/// provided in this case to alter the static variable. **This is intended for testing ONLY and is
/// ONLY available when `std` is enabled.**
///
/// # Examples
///
/// ```
/// # use frame_support::traits::Get;
/// # use frame_support::parameter_types;
/// // This function cannot be used in a const context.
/// fn non_const_expression() -> u64 { 99 }
///
/// const FIXED_VALUE: u64 = 10;
/// parameter_types! {
/// pub const Argument: u64 = 42 + FIXED_VALUE;
/// /// Visibility of the type is optional
/// OtherArgument: u64 = non_const_expression();
/// pub storage StorageArgument: u64 = 5;
/// pub static StaticArgument: u32 = 7;
/// }
///
/// trait Config {
/// type Parameter: Get<u64>;
/// type OtherParameter: Get<u64>;
/// type StorageParameter: Get<u64>;
/// type StaticParameter: Get<u32>;
/// }
///
/// struct Runtime;
/// impl Config for Runtime {
/// type Parameter = Argument;
/// type OtherParameter = OtherArgument;
/// type StorageParameter = StorageArgument;
/// type StaticParameter = StaticArgument;
/// }
///
/// // In testing, `StaticArgument` can be altered later: `StaticArgument::set(8)`.
/// ```
///
/// # Invalid example:
///
/// ```compile_fail
/// # use frame_support::traits::Get;
/// # use frame_support::parameter_types;
/// // This function cannot be used in a const context.
/// fn non_const_expression() -> u64 { 99 }
///
/// parameter_types! {
/// pub const Argument: u64 = non_const_expression();
/// }
/// ```
#[macro_export]
macro_rules! parameter_types {
(
$( #[ $attr:meta ] )*
$vis:vis const $name:ident $(< $($ty_params:ident),* >)?: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name $(
< $($ty_params),* >( $(core::marker::PhantomData<$ty_params>),* )
)?;
$crate::parameter_types!(IMPL_CONST $name , $type , $value $( $(, $ty_params)* )?);
$crate::parameter_types!( $( $rest )* );
);
(
$( #[ $attr:meta ] )*
$vis:vis $name:ident $(< $($ty_params:ident),* >)?: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name $(
< $($ty_params),* >( $(core::marker::PhantomData<$ty_params>),* )
)?;
$crate::parameter_types!(IMPL $name, $type, $value $( $(, $ty_params)* )?);
$crate::parameter_types!( $( $rest )* );
);
(
$( #[ $attr:meta ] )*
$vis:vis storage $name:ident $(< $($ty_params:ident),* >)?: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name $(
< $($ty_params),* >( $(core::marker::PhantomData<$ty_params>),* )
)?;
$crate::parameter_types!(IMPL_STORAGE $name, $type, $value $( $(, $ty_params)* )?);
$crate::parameter_types!( $( $rest )* );
);
() => ();
(IMPL_CONST $name:ident, $type:ty, $value:expr $(, $ty_params:ident)*) => {
impl< $($ty_params),* > $name< $($ty_params),* > {
/// Returns the value of this parameter type.
pub const fn get() -> $type {
$value
}
}
impl<_I: From<$type> $(, $ty_params)*> $crate::traits::Get<_I> for $name< $($ty_params),* > {
fn get() -> _I {
_I::from(Self::get())
}
}
impl< $($ty_params),* > $crate::traits::TypedGet for $name< $($ty_params),* > {
type Type = $type;
fn get() -> $type {
Self::get()
}
}
};
(IMPL $name:ident, $type:ty, $value:expr $(, $ty_params:ident)*) => {
impl< $($ty_params),* > $name< $($ty_params),* > {
/// Returns the value of this parameter type.
pub fn get() -> $type {
$value
}
}
impl<_I: From<$type>, $(, $ty_params)*> $crate::traits::Get<_I> for $name< $($ty_params),* > {
fn get() -> _I {
_I::from(Self::get())
}
}
impl< $($ty_params),* > $crate::traits::TypedGet for $name< $($ty_params),* > {
type Type = $type;
fn get() -> $type {
Self::get()
}
}
};
(IMPL_STORAGE $name:ident, $type:ty, $value:expr $(, $ty_params:ident)*) => {
#[allow(unused)]
impl< $($ty_params),* > $name< $($ty_params),* > {
/// Returns the key for this parameter type.
pub fn key() -> [u8; 16] {
$crate::__private::sp_crypto_hashing_proc_macro::twox_128!(b":", $name, b":")
}
/// Set the value of this parameter type in the storage.
///
/// This needs to be executed in an externalities provided environment.
pub fn set(value: &$type) {
$crate::storage::unhashed::put(&Self::key(), value);
}
/// Returns the value of this parameter type.
///
/// This needs to be executed in an externalities provided environment.
#[allow(unused)]
pub fn get() -> $type {
$crate::storage::unhashed::get(&Self::key()).unwrap_or_else(|| $value)
}
}
impl<_I: From<$type> $(, $ty_params)*> $crate::traits::Get<_I> for $name< $($ty_params),* > {
fn get() -> _I {
_I::from(Self::get())
}
}
impl< $($ty_params),* > $crate::traits::TypedGet for $name< $($ty_params),* > {
type Type = $type;
fn get() -> $type {
Self::get()
}
}
};
(
$( #[ $attr:meta ] )*
$vis:vis static $name:ident: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$crate::parameter_types_impl_thread_local!(
$( #[ $attr ] )*
$vis static $name: $type = $value;
);
$crate::parameter_types!( $( $rest )* );
);
}
#[cfg(not(feature = "std"))]
#[macro_export]
macro_rules! parameter_types_impl_thread_local {
( $( $any:tt )* ) => {
compile_error!("static parameter types is only available in std and for testing.");
};
}
#[cfg(feature = "std")]
#[macro_export]
macro_rules! parameter_types_impl_thread_local {
(
$(
$( #[ $attr:meta ] )*
$vis:vis static $name:ident: $type:ty = $value:expr;
)*
) => {
$crate::parameter_types_impl_thread_local!(
IMPL_THREAD_LOCAL $( $vis, $name, $type, $value, )*
);
$crate::__private::paste::item! {
$crate::parameter_types!(
$(
$( #[ $attr ] )*
$vis $name: $type = [<$name:snake:upper>].with(|v| v.borrow().clone());
)*
);
$(
impl $name {
/// Set the internal value.
pub fn set(t: $type) {
[<$name:snake:upper>].with(|v| *v.borrow_mut() = t);
}
/// Mutate the internal value in place.
#[allow(unused)]
pub fn mutate<R, F: FnOnce(&mut $type) -> R>(mutate: F) -> R{
let mut current = Self::get();
let result = mutate(&mut current);
Self::set(current);
result
}
/// Get current value and replace with initial value of the parameter type.
#[allow(unused)]
pub fn take() -> $type {
let current = Self::get();
Self::set($value);
current
}
}
)*
}
};
(IMPL_THREAD_LOCAL $( $vis:vis, $name:ident, $type:ty, $value:expr, )* ) => {
$crate::__private::paste::item! {
thread_local! {
$(
pub static [<$name:snake:upper>]: std::cell::RefCell<$type> =
std::cell::RefCell::new($value);
)*
}
}
};
}
/// Macro for easily creating a new implementation of both the `Get` and `Contains` traits. Use
/// exactly as with `parameter_types`, only the type must be `Ord`.
#[macro_export]
macro_rules! ord_parameter_types {
(
$( #[ $attr:meta ] )*
$vis:vis const $name:ident: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name;
$crate::parameter_types!{IMPL $name , $type , $value}
$crate::ord_parameter_types!{IMPL $name , $type , $value}
$crate::ord_parameter_types!{ $( $rest )* }
);
() => ();
(IMPL $name:ident , $type:ty , $value:expr) => {
impl $crate::traits::SortedMembers<$type> for $name {
fn contains(t: &$type) -> bool { &$value == t }
fn sorted_members() -> $crate::__private::Vec<$type> { vec![$value] }
fn count() -> usize { 1 }
#[cfg(feature = "runtime-benchmarks")]
fn add(_: &$type) {}
}
impl $crate::traits::Contains<$type> for $name {
fn contains(t: &$type) -> bool { &$value == t }
}
}
}
/// Print out a formatted message.
///
/// # Example
///
/// ```
/// frame_support::runtime_print!("my value is {}", 3);
/// ```
#[macro_export]
macro_rules! runtime_print {
($($arg:tt)+) => {
{
use core::fmt::Write;
let mut w = $crate::__private::sp_std::Writer::default();
let _ = core::write!(&mut w, $($arg)+);
$crate::__private::sp_io::misc::print_utf8(&w.inner())
}
}
}
/// Print out the debuggable type.
pub fn debug(data: &impl core::fmt::Debug) {
runtime_print!("{:?}", data);
}
#[doc(inline)]
pub use frame_support_procedural::{
construct_runtime, match_and_insert, transactional, PalletError, RuntimeDebugNoBound,
};
pub use frame_support_procedural::runtime;
#[doc(hidden)]
pub use frame_support_procedural::{__create_tt_macro, __generate_dummy_part_checker};
/// Derive [`Clone`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::CloneNoBound;
/// trait Config {
/// type C: Clone;
/// }
///
/// // Foo implements [`Clone`] because `C` bounds [`Clone`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Clone`].
/// #[derive(CloneNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::CloneNoBound;
/// Derive [`Eq`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::{EqNoBound, PartialEqNoBound};
/// trait Config {
/// type C: Eq;
/// }
///
/// // Foo implements [`Eq`] because `C` bounds [`Eq`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Eq`].
/// #[derive(PartialEqNoBound, EqNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::EqNoBound;
/// Derive [`PartialEq`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::PartialEqNoBound;
/// trait Config {
/// type C: PartialEq;
/// }
///
/// // Foo implements [`PartialEq`] because `C` bounds [`PartialEq`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`PartialEq`].
/// #[derive(PartialEqNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::PartialEqNoBound;
/// Derive [`Ord`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::{OrdNoBound, PartialOrdNoBound, EqNoBound, PartialEqNoBound};
/// trait Config {
/// type C: Ord;
/// }
///
/// // Foo implements [`Ord`] because `C` bounds [`Ord`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Ord`].
/// #[derive(EqNoBound, OrdNoBound, PartialEqNoBound, PartialOrdNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::OrdNoBound;
/// Derive [`PartialOrd`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::{OrdNoBound, PartialOrdNoBound, EqNoBound, PartialEqNoBound};
/// trait Config {
/// type C: PartialOrd;
/// }
///
/// // Foo implements [`PartialOrd`] because `C` bounds [`PartialOrd`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`PartialOrd`].
/// #[derive(PartialOrdNoBound, PartialEqNoBound, EqNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::PartialOrdNoBound;
/// Derive [`Debug`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::DebugNoBound;
/// # use core::fmt::Debug;
/// trait Config {
/// type C: Debug;
/// }
///
/// // Foo implements [`Debug`] because `C` bounds [`Debug`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Debug`].
/// #[derive(DebugNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::DebugNoBound;
/// Derive [`Default`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::DefaultNoBound;
/// # use core::default::Default;
/// trait Config {
/// type C: Default;
/// }
///
/// // Foo implements [`Default`] because `C` bounds [`Default`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Default`].
/// #[derive(DefaultNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
///
/// // Also works with enums, by specifying the default with #[default]:
/// #[derive(DefaultNoBound)]
/// enum Bar<T: Config> {
/// // Bar will implement Default as long as all of the types within Baz also implement default.
/// #[default]
/// Baz(T::C),
/// Quxx,
/// }
/// ```
pub use frame_support_procedural::DefaultNoBound;
/// Assert the annotated function is executed within a storage transaction.
///
/// The assertion is enabled for native execution and when `debug_assertions` are enabled.
///
/// # Example
///
/// ```
/// # use frame_support::{
/// # require_transactional, transactional, dispatch::DispatchResult
/// # };
///
/// #[require_transactional]
/// fn update_all(value: u32) -> DispatchResult {
/// // Update multiple storages.
/// // Return `Err` to indicate should revert.
/// Ok(())
/// }
///
/// #[transactional]
/// fn safe_update(value: u32) -> DispatchResult {
/// // This is safe
/// update_all(value)
/// }
///
/// fn unsafe_update(value: u32) -> DispatchResult {
/// // this may panic if unsafe_update is not called within a storage transaction
/// update_all(value)
/// }
/// ```
pub use frame_support_procedural::require_transactional;
/// Convert the current crate version into a [`CrateVersion`](crate::traits::CrateVersion).
///
/// It uses the `CARGO_PKG_VERSION_MAJOR`, `CARGO_PKG_VERSION_MINOR` and
/// `CARGO_PKG_VERSION_PATCH` environment variables to fetch the crate version.
/// This means that the [`CrateVersion`](crate::traits::CrateVersion)
/// object will correspond to the version of the crate the macro is called in!
///
/// # Example
///
/// ```
/// # use frame_support::{traits::CrateVersion, crate_to_crate_version};
/// const Version: CrateVersion = crate_to_crate_version!();
/// ```
pub use frame_support_procedural::crate_to_crate_version;
/// Return Err of the expression: `return Err($expression);`.
///
/// Used as `fail!(expression)`.
#[macro_export]
macro_rules! fail {
( $y:expr ) => {{
return Err($y.into());
}};
}
/// Evaluate `$x:expr` and if not true return `Err($y:expr)`.
///
/// Used as `ensure!(expression_to_ensure, expression_to_return_on_false)`.
#[macro_export]
macro_rules! ensure {
( $x:expr, $y:expr $(,)? ) => {{
if !$x {
$crate::fail!($y);
}
}};
}
/// Evaluate an expression, assert it returns an expected `Err` value and that
/// runtime storage has not been mutated (i.e. expression is a no-operation).
///
/// Used as `assert_noop(expression_to_assert, expected_error_expression)`.
#[macro_export]
macro_rules! assert_noop {
(
$x:expr,
$y:expr $(,)?
) => {
let h = $crate::__private::storage_root($crate::__private::StateVersion::V1);
$crate::assert_err!($x, $y);
assert_eq!(
h,
$crate::__private::storage_root($crate::__private::StateVersion::V1),
"storage has been mutated"
);
};
}
/// Evaluate any expression and assert that runtime storage has not been mutated
/// (i.e. expression is a storage no-operation).
///
/// Used as `assert_storage_noop(expression_to_assert)`.
#[macro_export]
macro_rules! assert_storage_noop {
(
$x:expr
) => {
let h = $crate::__private::storage_root($crate::__private::StateVersion::V1);
$x;
assert_eq!(h, $crate::__private::storage_root($crate::__private::StateVersion::V1));
};
}
/// Assert an expression returns an error specified.
///
/// Used as `assert_err!(expression_to_assert, expected_error_expression)`
#[macro_export]
macro_rules! assert_err {
( $x:expr , $y:expr $(,)? ) => {
assert_eq!($x, Err($y.into()));
};
}
/// Assert an expression returns an error specified.
///
/// This can be used on `DispatchResultWithPostInfo` when the post info should
/// be ignored.
#[macro_export]
macro_rules! assert_err_ignore_postinfo {
( $x:expr , $y:expr $(,)? ) => {
$crate::assert_err!($x.map(|_| ()).map_err(|e| e.error), $y);
};
}
/// Assert an expression returns error with the given weight.
#[macro_export]
macro_rules! assert_err_with_weight {
($call:expr, $err:expr, $weight:expr $(,)? ) => {
if let Err(dispatch_err_with_post) = $call {
$crate::assert_err!($call.map(|_| ()).map_err(|e| e.error), $err);
assert_eq!(dispatch_err_with_post.post_info.actual_weight, $weight);
} else {
::core::panic!("expected Err(_), got Ok(_).")
}
};
}
/// Panic if an expression doesn't evaluate to `Ok`.
///
/// Used as `assert_ok!(expression_to_assert, expected_ok_expression)`,
/// or `assert_ok!(expression_to_assert)` which would assert against `Ok(())`.
#[macro_export]
macro_rules! assert_ok {
( $x:expr $(,)? ) => {
let is = $x;
match is {
Ok(_) => (),
_ => assert!(false, "Expected Ok(_). Got {:#?}", is),
}
};
( $x:expr, $y:expr $(,)? ) => {
assert_eq!($x, Ok($y));
};
}
/// Assert that the maximum encoding size does not exceed the value defined in
/// [`MAX_MODULE_ERROR_ENCODED_SIZE`] during compilation.
///
/// This macro is intended to be used in conjunction with `tt_call!`.
#[macro_export]
macro_rules! assert_error_encoded_size {
{
path = [{ $($path:ident)::+ }]
runtime = [{ $runtime:ident }]
assert_message = [{ $assert_message:literal }]
error = [{ $error:ident }]
} => {
const _: () = assert!(
<
$($path::)+$error<$runtime> as $crate::traits::PalletError
>::MAX_ENCODED_SIZE <= $crate::MAX_MODULE_ERROR_ENCODED_SIZE,
$assert_message
);
};
{
path = [{ $($path:ident)::+ }]
runtime = [{ $runtime:ident }]
assert_message = [{ $assert_message:literal }]
} => {};
}
/// Do something hypothetically by rolling back any changes afterwards.
///
/// Returns the original result of the closure.
#[macro_export]
#[cfg(feature = "experimental")]
macro_rules! hypothetically {
( $e:expr ) => {
$crate::storage::transactional::with_transaction(|| -> $crate::__private::TransactionOutcome<Result<_, $crate::__private::DispatchError>> {
$crate::__private::TransactionOutcome::Rollback(Ok($e))
},
).expect("Always returning Ok; qed")
};
}
/// Assert something to be *hypothetically* `Ok`, without actually committing it.
///
/// Reverts any storage changes made by the closure.
#[macro_export]
#[cfg(feature = "experimental")]
macro_rules! hypothetically_ok {
($e:expr $(, $args:expr)* $(,)?) => {
$crate::assert_ok!($crate::hypothetically!($e) $(, $args)*);
};
}
#[doc(hidden)]
pub use serde::{Deserialize, Serialize};
#[doc(hidden)]
pub use macro_magic;
/// Prelude to be used for pallet testing, for ease of use.
#[cfg(feature = "std")]
pub mod testing_prelude {
pub use super::{
assert_err, assert_err_ignore_postinfo, assert_err_with_weight, assert_error_encoded_size,
assert_noop, assert_ok, assert_storage_noop, parameter_types, traits::Get,
};
pub use sp_arithmetic::assert_eq_error_rate;
pub use sp_runtime::{bounded_btree_map, bounded_vec};
}
/// Prelude to be used alongside pallet macro, for ease of use.
pub mod pallet_prelude {
pub use crate::{
defensive, defensive_assert,
dispatch::{DispatchClass, DispatchResult, DispatchResultWithPostInfo, Parameter, Pays},
ensure,
inherent::{InherentData, InherentIdentifier, ProvideInherent},
storage,
storage::{
bounded_btree_map::BoundedBTreeMap,
bounded_btree_set::BoundedBTreeSet,
bounded_vec::BoundedVec,
types::{
CountedStorageMap, CountedStorageNMap, Key as NMapKey, OptionQuery, ResultQuery,
StorageDoubleMap, StorageMap, StorageNMap, StorageValue, ValueQuery,
},
weak_bounded_vec::WeakBoundedVec,
StorageList,
},
traits::{
BuildGenesisConfig, ConstU32, EnsureOrigin, Get, GetDefault, GetStorageVersion, Hooks,
IsType, PalletInfoAccess, StorageInfoTrait, StorageVersion, Task, TypedGet,
},
Blake2_128, Blake2_128Concat, Blake2_256, CloneNoBound, DebugNoBound, EqNoBound, Identity,
PartialEqNoBound, RuntimeDebugNoBound, Twox128, Twox256, Twox64Concat,
};
pub use codec::{Decode, Encode, MaxEncodedLen};
pub use core::marker::PhantomData;
pub use frame_support::pallet_macros::*;
pub use frame_support_procedural::{inject_runtime_type, register_default_impl};
pub use scale_info::TypeInfo;
pub use sp_inherents::MakeFatalError;
pub use sp_runtime::{
traits::{MaybeSerializeDeserialize, Member, ValidateUnsigned},
transaction_validity::{
InvalidTransaction, TransactionLongevity, TransactionPriority, TransactionSource,
TransactionTag, TransactionValidity, TransactionValidityError, UnknownTransaction,
ValidTransaction,
},
DispatchError, RuntimeDebug, MAX_MODULE_ERROR_ENCODED_SIZE,
};
pub use sp_weights::Weight;
}
/// The pallet macro has 2 purposes:
///
/// * [For declaring a pallet as a rust module](#1---pallet-module-declaration)
/// * [For declaring the `struct` placeholder of a
/// pallet](#2---pallet-struct-placeholder-declaration)
///
/// # 1 - Pallet module declaration
///
/// The module to declare a pallet is organized as follows:
/// ```
/// #[frame_support::pallet] // <- the macro
/// mod pallet {
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {}
///
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// }
///
/// /* ... */
/// }
/// ```
///
/// The documentation for each individual part can be found at [frame_support::pallet_macros]
///
/// ## Dev Mode (`#[pallet(dev_mode)]`)
///
/// Syntax:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// /* ... */
/// }
/// ```
///
/// Specifying the argument `dev_mode` will allow you to enable dev mode for a pallet. The
/// aim of dev mode is to loosen some of the restrictions and requirements placed on
/// production pallets for easy tinkering and development. Dev mode pallets should not be
/// used in production. Enabling dev mode has the following effects:
///
/// * Weights no longer need to be specified on every `#[pallet::call]` declaration. By
/// default, dev mode pallets will assume a weight of zero (`0`) if a weight is not
/// specified. This is equivalent to specifying `#[weight(0)]` on all calls that do not
/// specify a weight.
/// * Call indices no longer need to be specified on every `#[pallet::call]` declaration. By
/// default, dev mode pallets will assume a call index based on the order of the call.
/// * All storages are marked as unbounded, meaning you do not need to implement
/// [`MaxEncodedLen`](frame_support::pallet_prelude::MaxEncodedLen) on storage types. This is
/// equivalent to specifying `#[pallet::unbounded]` on all storage type definitions.
/// * Storage hashers no longer need to be specified and can be replaced by `_`. In dev mode,
/// these will be replaced by `Blake2_128Concat`. In case of explicit key-binding, `Hasher`
/// can simply be ignored when in `dev_mode`.
///
/// Note that the `dev_mode` argument can only be supplied to the `#[pallet]` or
/// `#[frame_support::pallet]` attribute macro that encloses your pallet module. This
/// argument cannot be specified anywhere else, including but not limited to the
/// `#[pallet::pallet]` attribute macro.
///
/// <div class="example-wrap" style="display:inline-block"><pre class="compile_fail"
/// style="white-space:normal;font:inherit;">
/// <strong>WARNING</strong>:
/// You should never deploy or use dev mode pallets in production. Doing so can break your
/// chain. Once you are done tinkering, you should
/// remove the 'dev_mode' argument from your #[pallet] declaration and fix any compile
/// errors before attempting to use your pallet in a production scenario.
/// </pre></div>
///
/// # 2 - Pallet struct placeholder declaration
///
/// The pallet struct placeholder `#[pallet::pallet]` is mandatory and allows you to
/// specify pallet information.
///
/// The struct must be defined as follows:
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// #[pallet::pallet] // <- the macro
/// pub struct Pallet<T>(_); // <- the struct definition
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {}
/// }
/// ```
//
/// I.e. a regular struct definition named `Pallet`, with generic T and no where clause.
///
/// ## Macro expansion:
///
/// The macro adds this attribute to the Pallet struct definition:
/// ```ignore
/// #[derive(
/// frame_support::CloneNoBound,
/// frame_support::EqNoBound,
/// frame_support::PartialEqNoBound,
/// frame_support::RuntimeDebugNoBound,
/// )]
/// ```
/// and replaces the type `_` with `PhantomData<T>`.
///
/// It also implements on the pallet:
///
/// * [`GetStorageVersion`](frame_support::traits::GetStorageVersion)
/// * [`OnGenesis`](frame_support::traits::OnGenesis): contains some logic to write the pallet
/// version into storage.
/// * [`PalletInfoAccess`](frame_support::traits::PalletInfoAccess) to ease access to pallet
/// information given by [`frame_support::traits::PalletInfo`]. (The implementation uses the
/// associated type [`frame_support::traits::PalletInfo`]).
/// * [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) to give information about
/// storages.
///
/// If the attribute `set_storage_max_encoded_len` is set then the macro calls
/// [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) for each storage in the
/// implementation of [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) for the
/// pallet. Otherwise, it implements
/// [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) for the pallet using the
/// [`PartialStorageInfoTrait`](frame_support::traits::PartialStorageInfoTrait)
/// implementation of storages.
///
/// ## Note on deprecation.
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::pallet;
/// Contains macro stubs for all of the `pallet::` macros
pub mod pallet_macros {
/// Declare the storage as whitelisted from benchmarking.
///
/// Doing so will exclude reads of that value's storage key from counting towards weight
/// calculations during benchmarking.
///
/// This attribute should only be attached to storages that are known to be
/// read/used in every block. This will result in a more accurate benchmarking weight.
///
/// ### Example
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::whitelist_storage]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::whitelist_storage;
/// Allows specifying the weight of a call.
///
/// Each dispatchable needs to define a weight with the `#[pallet::weight($expr)]`
/// attribute. The first argument must be `origin: OriginFor<T>`.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// #[pallet::weight({0})] // <- set actual weight here
/// #[pallet::call_index(0)]
/// pub fn something(
/// _: OriginFor<T>,
/// foo: u32,
/// ) -> DispatchResult {
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::weight;
/// Allows whitelisting a storage item from decoding during try-runtime checks.
///
/// The optional attribute `#[pallet::disable_try_decode_storage]` will declare the
/// storage as whitelisted from decoding during try-runtime checks. This should only be
/// attached to transient storage which cannot be migrated during runtime upgrades.
///
/// ### Example
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::disable_try_decode_storage]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::disable_try_decode_storage;
/// Declares a storage as unbounded in potential size.
///
/// When implementing the storage info (when `#[pallet::generate_storage_info]` is
/// specified on the pallet struct placeholder), the size of the storage will be declared
/// as unbounded. This can be useful for storage which can never go into PoV (Proof of
/// Validity).
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::unbounded]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::unbounded;
/// Defines what storage prefix to use for a storage item when building the trie.
///
/// This is helpful if you wish to rename the storage field but don't want to perform a
/// migration.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::storage_prefix = "foo"]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::storage_prefix;
/// Ensures the generated `DefaultConfig` will not have any bounds for
/// that trait item.
///
/// Attaching this attribute to a trait item ensures that the generated trait
/// `DefaultConfig` will not have any bounds for this trait item.
///
/// As an example, if you have a trait item `type AccountId: SomeTrait;` in your `Config`
/// trait, the generated `DefaultConfig` will only have `type AccountId;` with no trait
/// bound.
pub use frame_support_procedural::no_default_bounds;
/// Ensures the trait item will not be used as a default with the
/// `#[derive_impl(..)]` attribute macro.
///
/// The optional attribute `#[pallet::no_default]` can be attached to trait items within a
/// `Config` trait impl that has [`#[pallet::config(with_default)]`](`config`)
/// attached.
pub use frame_support_procedural::no_default;
/// Declares a module as importable into a pallet via
/// [`#[import_section]`](`import_section`).
///
/// Note that sections are imported by their module name/ident, and should be referred to
/// by their _full path_ from the perspective of the target pallet. Do not attempt to make
/// use of `use` statements to bring pallet sections into scope, as this will not work
/// (unless you do so as part of a wildcard import, in which case it will work).
///
/// ## Naming Logistics
///
/// Also note that because of how `#[pallet_section]` works, pallet section names must be
/// globally unique _within the crate in which they are defined_. For more information on
/// why this must be the case, see macro_magic's
/// [`#[export_tokens]`](https://docs.rs/macro_magic/latest/macro_magic/attr.export_tokens.html) macro.
///
/// Optionally, you may provide an argument to `#[pallet_section]` such as
/// `#[pallet_section(some_ident)]`, in the event that there is another pallet section in
/// same crate with the same ident/name. The ident you specify can then be used instead of
/// the module's ident name when you go to import it via
/// [`#[import_section]`](`import_section`).
pub use frame_support_procedural::pallet_section;
/// The `#[pallet::inherent]` attribute allows the pallet to provide
/// [inherents](https://docs.substrate.io/fundamentals/transaction-types/#inherent-transactions).
///
/// An inherent is some piece of data that is inserted by a block authoring node at block
/// creation time and can either be accepted or rejected by validators based on whether the
/// data falls within an acceptable range.
///
/// The most common inherent is the `timestamp` that is inserted into every block. Since
/// there is no way to validate timestamps, validators simply check that the timestamp
/// reported by the block authoring node falls within an acceptable range.
///
/// Example usage:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_support::inherent::IsFatalError;
/// # use sp_timestamp::InherentError;
/// # use core::result;
/// #
/// // Example inherent identifier
/// pub const INHERENT_IDENTIFIER: InherentIdentifier = *b"timstap0";
///
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::inherent]
/// impl<T: Config> ProvideInherent for Pallet<T> {
/// type Call = Call<T>;
/// type Error = InherentError;
/// const INHERENT_IDENTIFIER: InherentIdentifier = INHERENT_IDENTIFIER;
///
/// fn create_inherent(data: &InherentData) -> Option<Self::Call> {
/// unimplemented!()
/// }
///
/// fn check_inherent(
/// call: &Self::Call,
/// data: &InherentData,
/// ) -> result::Result<(), Self::Error> {
/// unimplemented!()
/// }
///
/// fn is_inherent(call: &Self::Call) -> bool {
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// I.e. a trait implementation with bound `T: Config`, of trait `ProvideInherent` for type
/// `Pallet<T>`, and some optional where clause.
///
/// ## Macro expansion
///
/// The macro currently makes no use of this information, but it might use this information
/// in the future to give information directly to `construct_runtime`.
pub use frame_support_procedural::inherent;
/// Splits a pallet declaration into multiple parts.
///
/// An attribute macro that can be attached to a module declaration. Doing so will
/// import the contents of the specified external pallet section that is defined
/// elsewhere using [`#[pallet_section]`](`pallet_section`).
///
/// ## Example
/// ```
/// # use frame_support::pallet_macros::pallet_section;
/// # use frame_support::pallet_macros::import_section;
/// #
/// /// A [`pallet_section`] that defines the events for a pallet.
/// /// This can later be imported into the pallet using [`import_section`].
/// #[pallet_section]
/// mod events {
/// #[pallet::event]
/// #[pallet::generate_deposit(pub(super) fn deposit_event)]
/// pub enum Event<T: Config> {
/// /// Event documentation should end with an array that provides descriptive names for event
/// /// parameters. [something, who]
/// SomethingStored { something: u32, who: T::AccountId },
/// }
/// }
///
/// #[import_section(events)]
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {
/// # type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
/// # }
/// }
/// ```
///
/// This will result in the contents of `some_section` being _verbatim_ imported into
/// the pallet above. Note that since the tokens for `some_section` are essentially
/// copy-pasted into the target pallet, you cannot refer to imports that don't also
/// exist in the target pallet, but this is easily resolved by including all relevant
/// `use` statements within your pallet section, so they are imported as well, or by
/// otherwise ensuring that you have the same imports on the target pallet.
///
/// It is perfectly permissible to import multiple pallet sections into the same pallet,
/// which can be done by having multiple `#[import_section(something)]` attributes
/// attached to the pallet.
///
/// Note that sections are imported by their module name/ident, and should be referred to
/// by their _full path_ from the perspective of the target pallet.
pub use frame_support_procedural::import_section;
/// Allows defining getter functions on `Pallet` storage.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::getter(fn my_getter_fn_name)]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// See [`pallet::storage`](`frame_support::pallet_macros::storage`) for more info.
pub use frame_support_procedural::getter;
/// Defines constants that are added to the constant field of
/// [`PalletMetadata`](frame_metadata::v15::PalletMetadata) struct for this pallet.
///
/// Must be defined like:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// #
/// #[pallet::extra_constants]
/// impl<T: Config> Pallet<T> // $optional_where_clause
/// {
/// #[pallet::constant_name(SomeU32ConstantName)]
/// /// Some doc
/// fn some_u32_constant() -> u32 {
/// 100u32
/// }
/// }
/// }
/// ```
///
/// I.e. a regular rust `impl` block with some optional where clause and functions with 0
/// args, 0 generics, and some return type.
pub use frame_support_procedural::extra_constants;
#[rustfmt::skip]
/// Allows bypassing the `frame_system::Config` supertrait check.
///
/// To bypass the syntactic `frame_system::Config` supertrait check, use the attribute
/// `pallet::disable_frame_system_supertrait_check`.
///
/// Note this bypass is purely syntactic, and does not actually remove the requirement that your
/// pallet implements `frame_system::Config`. When using this check, your config is still required to implement
/// `frame_system::Config` either via
/// - Implementing a trait that itself implements `frame_system::Config`
/// - Tightly coupling it with another pallet which itself implements `frame_system::Config`
///
/// e.g.
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// trait OtherTrait: frame_system::Config {}
///
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config]
/// #[pallet::disable_frame_system_supertrait_check]
/// pub trait Config: OtherTrait {}
/// }
/// ```
///
/// To learn more about supertraits, see the
/// [trait_based_programming](../../polkadot_sdk_docs/reference_docs/trait_based_programming/index.html)
/// reference doc.
pub use frame_support_procedural::disable_frame_system_supertrait_check;
/// The mandatory attribute allowing definition of configurable types for the pallet.
///
/// Item must be defined as:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config // + $optionally_some_other_supertraits
/// // $optional_where_clause
/// {
/// // config items here
/// }
/// }
/// ```
///
/// I.e. a regular trait definition named `Config`, with the supertrait
/// [`frame_system::pallet::Config`](../../frame_system/pallet/trait.Config.html), and
/// optionally other supertraits and a where clause. (Specifying other supertraits here is
/// known as [tight coupling](https://docs.substrate.io/reference/how-to-guides/pallet-design/use-tight-coupling/))
///
/// The associated type `RuntimeEvent` is reserved. If defined, it must have the bounds
/// `From<Event>` and `IsType<<Self as frame_system::Config>::RuntimeEvent>`.
///
/// [`#[pallet::event]`](`event`) must be present if `RuntimeEvent`
/// exists as a config item in your `#[pallet::config]`.
///
/// ## Optional: `with_default`
///
/// An optional `with_default` argument may also be specified. Doing so will automatically
/// generate a `DefaultConfig` trait inside your pallet which is suitable for use with
/// [`#[derive_impl(..)`](`frame_support::derive_impl`) to derive a default testing
/// config:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// # use core::fmt::Debug;
/// # use frame_support::traits::Contains;
/// #
/// # pub trait SomeMoreComplexBound {}
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config(with_default)] // <- with_default is optional
/// pub trait Config: frame_system::Config {
/// /// The overarching event type.
/// #[pallet::no_default_bounds] // Default with bounds is not supported for RuntimeEvent
/// type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
///
/// /// A more complex type.
/// #[pallet::no_default] // Example of type where no default should be provided
/// type MoreComplexType: SomeMoreComplexBound;
///
/// /// A simple type.
/// // Default with bounds is supported for simple types
/// type SimpleType: From<u32>;
/// }
///
/// #[pallet::event]
/// pub enum Event<T: Config> {
/// SomeEvent(u16, u32),
/// }
/// }
/// ```
///
/// As shown above:
/// * you may attach the [`#[pallet::no_default]`](`no_default`)
/// attribute to specify that a particular trait item _cannot_ be used as a default when a
/// test `Config` is derived using the [`#[derive_impl(..)]`](`frame_support::derive_impl`)
/// attribute macro. This will cause that particular trait item to simply not appear in
/// default testing configs based on this config (the trait item will not be included in
/// `DefaultConfig`).
/// * you may attach the [`#[pallet::no_default_bounds]`](`no_default_bounds`)
/// attribute to specify that a particular trait item can be used as a default when a
/// test `Config` is derived using the [`#[derive_impl(..)]`](`frame_support::derive_impl`)
/// attribute macro. But its bounds cannot be enforced at this point and should be
/// discarded when generating the default config trait.
/// * you may not specify any attribute to generate a trait item in the default config
/// trait.
///
/// In case origin of error is not clear it is recommended to disable all default with
/// [`#[pallet::no_default]`](`no_default`) and enable them one by one.
///
/// ### `DefaultConfig` Caveats
///
/// The auto-generated `DefaultConfig` trait:
/// - is always a _subset_ of your pallet's `Config` trait.
/// - can only contain items that don't rely on externalities, such as
/// `frame_system::Config`.
///
/// Trait items that _do_ rely on externalities should be marked with
/// [`#[pallet::no_default]`](`no_default`)
///
/// Consequently:
/// - Any items that rely on externalities _must_ be marked with
/// [`#[pallet::no_default]`](`no_default`) or your trait will fail to compile when used
/// with [`derive_impl`](`frame_support::derive_impl`).
/// - Items marked with [`#[pallet::no_default]`](`no_default`) are entirely excluded from
/// the `DefaultConfig` trait, and therefore any impl of `DefaultConfig` doesn't need to
/// implement such items.
///
/// For more information, see:
/// * [`frame_support::derive_impl`].
/// * [`#[pallet::no_default]`](`no_default`)
/// * [`#[pallet::no_default_bounds]`](`no_default_bounds`)
pub use frame_support_procedural::config;
/// Allows defining an enum that gets composed as an aggregate enum by `construct_runtime`.
///
/// The `#[pallet::composite_enum]` attribute allows you to define an enum that gets
/// composed as an aggregate enum by `construct_runtime`. This is similar in principle with
/// [frame_support_procedural::event] and [frame_support_procedural::error].
///
/// The attribute currently only supports enum definitions, and identifiers that are named
/// `FreezeReason`, `HoldReason`, `LockId` or `SlashReason`. Arbitrary identifiers for the
/// enum are not supported. The aggregate enum generated by
/// [`frame_support::construct_runtime`] will have the name of `RuntimeFreezeReason`,
/// `RuntimeHoldReason`, `RuntimeLockId` and `RuntimeSlashReason` respectively.
///
/// NOTE: The aggregate enum generated by `construct_runtime` generates a conversion
/// function from the pallet enum to the aggregate enum, and automatically derives the
/// following traits:
///
/// ```ignore
/// Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, MaxEncodedLen, TypeInfo,
/// RuntimeDebug
/// ```
///
/// For ease of usage, when no `#[derive]` attributes are found for the enum under
/// [`#[pallet::composite_enum]`](composite_enum), the aforementioned traits are
/// automatically derived for it. The inverse is also true: if there are any `#[derive]`
/// attributes found for the enum, then no traits will automatically be derived for it.
///
/// e.g, defining `HoldReason` in a pallet
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::composite_enum]
/// pub enum HoldReason {
/// /// The NIS Pallet has reserved it for a non-fungible receipt.
/// #[codec(index = 0)]
/// SomeHoldReason,
/// #[codec(index = 1)]
/// SomeOtherHoldReason,
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
pub use frame_support_procedural::composite_enum;
/// Allows the pallet to validate unsigned transactions.
///
/// Item must be defined as:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::validate_unsigned]
/// impl<T: Config> sp_runtime::traits::ValidateUnsigned for Pallet<T> {
/// type Call = Call<T>;
///
/// fn validate_unsigned(_source: TransactionSource, _call: &Self::Call) -> TransactionValidity {
/// // Your implementation details here
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// I.e. a trait implementation with bound `T: Config`, of trait
/// [`ValidateUnsigned`](frame_support::pallet_prelude::ValidateUnsigned) for
/// type `Pallet<T>`, and some optional where clause.
///
/// NOTE: There is also the [`sp_runtime::traits::SignedExtension`] trait that can be used
/// to add some specific logic for transaction validation.
///
/// ## Macro expansion
///
/// The macro currently makes no use of this information, but it might use this information
/// in the future to give information directly to [`frame_support::construct_runtime`].
pub use frame_support_procedural::validate_unsigned;
/// Allows defining a struct implementing the [`Get`](frame_support::traits::Get) trait to
/// ease the use of storage types.
///
/// This attribute is meant to be used alongside [`#[pallet::storage]`](`storage`) to
/// define a storage's default value. This attribute can be used multiple times.
///
/// Item must be defined as:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use sp_runtime::FixedU128;
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// pub(super) type SomeStorage<T: Config> =
/// StorageValue<_, FixedU128, ValueQuery, DefaultForSomeValue>;
///
/// // Define default for ParachainId
/// #[pallet::type_value]
/// pub fn DefaultForSomeValue() -> FixedU128 {
/// FixedU128::from_u32(1)
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// ## Macro expansion
///
/// The macro renames the function to some internal name, generates a struct with the
/// original name of the function and its generic, and implements `Get<$ReturnType>` by
/// calling the user defined function.
pub use frame_support_procedural::type_value;
/// Allows defining a storage version for the pallet.
///
/// Because the `pallet::pallet` macro implements
/// [`GetStorageVersion`](frame_support::traits::GetStorageVersion), the current storage
/// version needs to be communicated to the macro. This can be done by using the
/// `pallet::storage_version` attribute:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::StorageVersion;
/// # use frame_support::traits::GetStorageVersion;
/// #
/// const STORAGE_VERSION: StorageVersion = StorageVersion::new(5);
///
/// #[pallet::pallet]
/// #[pallet::storage_version(STORAGE_VERSION)]
/// pub struct Pallet<T>(_);
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// If not present, the current storage version is set to the default value.
pub use frame_support_procedural::storage_version;
/// The `#[pallet::hooks]` attribute allows you to specify a
/// [`frame_support::traits::Hooks`] implementation for `Pallet` that specifies
/// pallet-specific logic.
///
/// The item the attribute attaches to must be defined as follows:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::hooks]
/// impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {
/// // Implement hooks here
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
/// I.e. a regular trait implementation with generic bound: `T: Config`, for the trait
/// `Hooks<BlockNumberFor<T>>` (they are defined in preludes), for the type `Pallet<T>`.
///
/// Optionally, you could add a where clause.
///
/// ## Macro expansion
///
/// The macro implements the traits
/// [`OnInitialize`](frame_support::traits::OnInitialize),
/// [`OnIdle`](frame_support::traits::OnIdle),
/// [`OnFinalize`](frame_support::traits::OnFinalize),
/// [`OnRuntimeUpgrade`](frame_support::traits::OnRuntimeUpgrade),
/// [`OffchainWorker`](frame_support::traits::OffchainWorker), and
/// [`IntegrityTest`](frame_support::traits::IntegrityTest) using
/// the provided [`Hooks`](frame_support::traits::Hooks) implementation.
///
/// NOTE: `OnRuntimeUpgrade` is implemented with `Hooks::on_runtime_upgrade` and some
/// additional logic. E.g. logic to write the pallet version into storage.
///
/// NOTE: The macro also adds some tracing logic when implementing the above traits. The
/// following hooks emit traces: `on_initialize`, `on_finalize` and `on_runtime_upgrade`.
pub use frame_support_procedural::hooks;
/// Generates a helper function on `Pallet` that handles deposit events.
///
/// NOTE: For instantiable pallets, the event must be generic over `T` and `I`.
///
/// ## Macro expansion
///
/// The macro will add on enum `Event` the attributes:
/// * `#[derive(`[`frame_support::CloneNoBound`]`)]`
/// * `#[derive(`[`frame_support::EqNoBound`]`)]`
/// * `#[derive(`[`frame_support::PartialEqNoBound`]`)]`
/// * `#[derive(`[`frame_support::RuntimeDebugNoBound`]`)]`
/// * `#[derive(`[`codec::Encode`]`)]`
/// * `#[derive(`[`codec::Decode`]`)]`
///
/// The macro implements `From<Event<..>>` for ().
///
/// The macro implements a metadata function on `Event` returning the `EventMetadata`.
///
/// If `#[pallet::generate_deposit]` is present then the macro implements `fn
/// deposit_event` on `Pallet`.
pub use frame_support_procedural::generate_deposit;
/// Allows defining logic to make an extrinsic call feeless.
///
/// Each dispatchable may be annotated with the `#[pallet::feeless_if($closure)]`
/// attribute, which explicitly defines the condition for the dispatchable to be feeless.
///
/// The arguments for the closure must be the referenced arguments of the dispatchable
/// function.
///
/// The closure must return `bool`.
///
/// ### Example
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// #[pallet::call_index(0)]
/// /// Marks this call as feeless if `foo` is zero.
/// #[pallet::feeless_if(|_origin: &OriginFor<T>, foo: &u32| -> bool {
/// *foo == 0
/// })]
/// pub fn something(
/// _: OriginFor<T>,
/// foo: u32,
/// ) -> DispatchResult {
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// Please note that this only works for signed dispatchables and requires a signed
/// extension such as [`pallet_skip_feeless_payment::SkipCheckIfFeeless`] to wrap the
/// existing payment extension. Else, this is completely ignored and the dispatchable is
/// still charged.
///
/// ### Macro expansion
///
/// The macro implements the [`pallet_skip_feeless_payment::CheckIfFeeless`] trait on the
/// dispatchable and calls the corresponding closure in the implementation.
///
/// [`pallet_skip_feeless_payment::SkipCheckIfFeeless`]: ../../pallet_skip_feeless_payment/struct.SkipCheckIfFeeless.html
/// [`pallet_skip_feeless_payment::CheckIfFeeless`]: ../../pallet_skip_feeless_payment/struct.SkipCheckIfFeeless.html
pub use frame_support_procedural::feeless_if;
/// Allows defining an error enum that will be returned from the dispatchable when an error
/// occurs.
///
/// The information for this error type is then stored in runtime metadata.
///
/// Item must be defined as so:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::error]
/// pub enum Error<T> {
/// /// SomeFieldLessVariant doc
/// SomeFieldLessVariant,
/// /// SomeVariantWithOneField doc
/// SomeVariantWithOneField(u32),
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
/// I.e. a regular enum named `Error`, with generic `T` and fieldless or multiple-field
/// variants.
///
/// Any field type in the enum variants must implement [`scale_info::TypeInfo`] in order to
/// be properly used in the metadata, and its encoded size should be as small as possible,
/// preferably 1 byte in size in order to reduce storage size. The error enum itself has an
/// absolute maximum encoded size specified by
/// [`frame_support::MAX_MODULE_ERROR_ENCODED_SIZE`].
///
/// (1 byte can still be 256 different errors. The more specific the error, the easier it
/// is to diagnose problems and give a better experience to the user. Don't skimp on having
/// lots of individual error conditions.)
///
/// Field types in enum variants must also implement [`frame_support::PalletError`],
/// otherwise the pallet will fail to compile. Rust primitive types have already
/// implemented the [`frame_support::PalletError`] trait along with some commonly used
/// stdlib types such as [`Option`] and [`core::marker::PhantomData`], and hence
/// in most use cases, a manual implementation is not necessary and is discouraged.
///
/// The generic `T` must not bound anything and a `where` clause is not allowed. That said,
/// bounds and/or a where clause should not needed for any use-case.
///
/// ## Macro expansion
///
/// The macro implements the [`Debug`] trait and functions `as_u8` using variant position,
/// and `as_str` using variant doc.
///
/// The macro also implements `From<Error<T>>` for `&'static str` and `From<Error<T>>` for
/// `DispatchError`.
///
/// ## Note on deprecation of Errors
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
/// - It's possible to deprecated either certain variants inside the `Error` or the whole
/// `Error` itself. If both the `Error` and its variants are deprecated a compile error
/// will be returned.
pub use frame_support_procedural::error;
/// Allows defining pallet events.
///
/// Pallet events are stored under the `system` / `events` key when the block is applied
/// (and then replaced when the next block writes it's events).
///
/// The Event enum can be defined as follows:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// # use frame_support::pallet_prelude::IsType;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::event]
/// #[pallet::generate_deposit(fn deposit_event)] // Optional
/// pub enum Event<T> {
/// /// SomeEvent doc
/// SomeEvent(u16, u32), // SomeEvent with two fields
/// }
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {
/// /// The overarching runtime event type.
/// type RuntimeEvent: From<Event<Self>>
/// + IsType<<Self as frame_system::Config>::RuntimeEvent>;
/// }
/// }
/// ```
///
/// I.e. an enum (with named or unnamed fields variant), named `Event`, with generic: none
/// or `T` or `T: Config`, and optional w here clause.
///
/// `RuntimeEvent` must be defined in the `Config`, as shown in the example.
///
/// Each field must implement [`Clone`], [`Eq`], [`PartialEq`], [`codec::Encode`],
/// [`codec::Decode`], and [`Debug`] (on std only). For ease of use, bound by the trait
/// `Member`, available in [`frame_support::pallet_prelude`].
///
/// ## Note on deprecation of Events
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
/// - It's possible to deprecated either certain variants inside the `Event` or the whole
/// `Event` itself. If both the `Event` and its variants are deprecated a compile error
/// will be returned.
pub use frame_support_procedural::event;
/// Allows a pallet to declare a set of functions as a *dispatchable extrinsic*.
///
/// In slightly simplified terms, this macro declares the set of "transactions" of a
/// pallet.
///
/// > The exact definition of **extrinsic** can be found in
/// > [`sp_runtime::generic::UncheckedExtrinsic`].
///
/// A **dispatchable** is a common term in FRAME, referring to process of constructing a
/// function, and dispatching it with the correct inputs. This is commonly used with
/// extrinsics, for example "an extrinsic has been dispatched". See
/// [`sp_runtime::traits::Dispatchable`] and [`crate::traits::UnfilteredDispatchable`].
///
/// ## Call Enum
///
/// The macro is called `call` (rather than `#[pallet::extrinsics]`) because of the
/// generation of a `enum Call`. This enum contains only the encoding of the function
/// arguments of the dispatchable, alongside the information needed to route it to the
/// correct function.
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// pub mod custom_pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::BuildGenesisConfig;
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// pub fn some_dispatchable(_origin: OriginFor<T>, _input: u32) -> DispatchResult {
/// Ok(())
/// }
/// pub fn other(_origin: OriginFor<T>, _input: u64) -> DispatchResult {
/// Ok(())
/// }
/// }
///
/// // generates something like:
/// // enum Call<T: Config> {
/// // some_dispatchable { input: u32 }
/// // other { input: u64 }
/// // }
/// }
///
/// fn main() {
/// # use frame_support::{derive_impl, construct_runtime};
/// # use frame_support::__private::codec::Encode;
/// # use frame_support::__private::TestExternalities;
/// # use frame_support::traits::UnfilteredDispatchable;
/// # impl custom_pallet::Config for Runtime {}
/// # #[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
/// # impl frame_system::Config for Runtime {
/// # type Block = frame_system::mocking::MockBlock<Self>;
/// # }
/// construct_runtime! {
/// pub enum Runtime {
/// System: frame_system,
/// Custom: custom_pallet
/// }
/// }
///
/// # TestExternalities::new_empty().execute_with(|| {
/// let origin: RuntimeOrigin = frame_system::RawOrigin::Signed(10).into();
/// // calling into a dispatchable from within the runtime is simply a function call.
/// let _ = custom_pallet::Pallet::<Runtime>::some_dispatchable(origin.clone(), 10);
///
/// // calling into a dispatchable from the outer world involves constructing the bytes of
/// let call = custom_pallet::Call::<Runtime>::some_dispatchable { input: 10 };
/// let _ = call.clone().dispatch_bypass_filter(origin);
///
/// // the routing of a dispatchable is simply done through encoding of the `Call` enum,
/// // which is the index of the variant, followed by the arguments.
/// assert_eq!(call.encode(), vec![0u8, 10, 0, 0, 0]);
///
/// // notice how in the encoding of the second function, the first byte is different and
/// // referring to the second variant of `enum Call`.
/// let call = custom_pallet::Call::<Runtime>::other { input: 10 };
/// assert_eq!(call.encode(), vec![1u8, 10, 0, 0, 0, 0, 0, 0, 0]);
/// # });
/// }
/// ```
///
/// Further properties of dispatchable functions are as follows:
///
/// - Unless if annotated by `dev_mode`, it must contain [`weight`] to denote the
/// pre-dispatch weight consumed.
/// - The dispatchable must declare its index via [`call_index`], which can override the
/// position of a function in `enum Call`.
/// - The first argument is always an `OriginFor` (or `T::RuntimeOrigin`).
/// - The return type is always [`crate::dispatch::DispatchResult`] (or
/// [`crate::dispatch::DispatchResultWithPostInfo`]).
///
/// **WARNING**: modifying dispatchables, changing their order (i.e. using [`call_index`]),
/// removing some, etc., must be done with care. This will change the encoding of the , and
/// the call can be stored on-chain (e.g. in `pallet-scheduler`). Thus, migration might be
/// needed. This is why the use of `call_index` is mandatory by default in FRAME.
///
/// ## Default Behavior
///
/// If no `#[pallet::call]` exists, then a default implementation corresponding to the
/// following code is automatically generated:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::call] // <- automatically generated
/// impl<T: Config> Pallet<T> {} // <- automatically generated
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// ## Note on deprecation of Calls
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::call;
/// Enforce the index of a variant in the generated `enum Call`.
///
/// See [`call`] for more information.
///
/// All call indexes start from 0, until it encounters a dispatchable function with a
/// defined call index. The dispatchable function that lexically follows the function with
/// a defined call index will have that call index, but incremented by 1, e.g. if there are
/// 3 dispatchable functions `fn foo`, `fn bar` and `fn qux` in that order, and only `fn
/// bar` has a call index of 10, then `fn qux` will have an index of 11, instead of 1.
pub use frame_support_procedural::call_index;
/// Declares the arguments of a [`call`] function to be encoded using
/// [`codec::Compact`].
///
/// This will results in smaller extrinsic encoding.
///
/// A common example of `compact` is for numeric values that are often times far far away
/// from their theoretical maximum. For example, in the context of a crypto-currency, the
/// balance of an individual account is oftentimes way less than what the numeric type
/// allows. In all such cases, using `compact` is sensible.
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// pub mod custom_pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::BuildGenesisConfig;
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// pub fn some_dispatchable(_origin: OriginFor<T>, #[pallet::compact] _input: u32) -> DispatchResult {
/// Ok(())
/// }
/// }
/// }
pub use frame_support_procedural::compact;
/// Allows you to define the genesis configuration for the pallet.
///
/// Item is defined as either an enum or a struct. It needs to be public and implement the
/// trait [`frame_support::traits::BuildGenesisConfig`].
///
/// See [`genesis_build`] for an example.
pub use frame_support_procedural::genesis_config;
/// Allows you to define how the state of your pallet at genesis is built. This
/// takes as input the `GenesisConfig` type (as `self`) and constructs the pallet's initial
/// state.
///
/// The fields of the `GenesisConfig` can in turn be populated by the chain-spec.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// pub mod pallet {
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::BuildGenesisConfig;
/// #[pallet::genesis_config]
/// #[derive(frame_support::DefaultNoBound)]
/// pub struct GenesisConfig<T: Config> {
/// foo: Vec<T::AccountId>
/// }
///
/// #[pallet::genesis_build]
/// impl<T: Config> BuildGenesisConfig for GenesisConfig<T> {
/// fn build(&self) {
/// // use &self to access fields.
/// let foo = &self.foo;
/// todo!()
/// }
/// }
/// }
/// ```
///
/// ## Former Usage
///
/// Prior to <https://github.com/paritytech/substrate/pull/14306>, the following syntax was used.
/// This is deprecated and will soon be removed.
///
/// ```
/// #[frame_support::pallet]
/// pub mod pallet {
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::GenesisBuild;
/// #[pallet::genesis_config]
/// #[derive(frame_support::DefaultNoBound)]
/// pub struct GenesisConfig<T: Config> {
/// foo: Vec<T::AccountId>
/// }
///
/// #[pallet::genesis_build]
/// impl<T: Config> GenesisBuild<T> for GenesisConfig<T> {
/// fn build(&self) {
/// todo!()
/// }
/// }
/// }
/// ```
pub use frame_support_procedural::genesis_build;
/// Allows adding an associated type trait bounded by
/// [`Get`](frame_support::pallet_prelude::Get) from [`pallet::config`](`macro@config`)
/// into metadata.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// use frame_support::pallet_prelude::*;
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// #[pallet::config]
/// pub trait Config: frame_system::Config {
/// /// This is like a normal `Get` trait, but it will be added into metadata.
/// #[pallet::constant]
/// type Foo: Get<u32>;
/// }
/// }
/// ```
///
/// ## Note on deprecation of constants
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::constant;
/// Declares a type alias as a storage item.
///
/// Storage items are pointers to data stored on-chain (the *blockchain state*), under a
/// specific key. The exact key is dependent on the type of the storage.
///
/// > From the perspective of this pallet, the entire blockchain state is abstracted behind
/// > a key-value api, namely [`sp_io::storage`].
///
/// ## Storage Types
///
/// The following storage types are supported by the `#[storage]` macro. For specific
/// information about each storage type, refer to the documentation of the respective type.
///
/// * [`StorageValue`](crate::storage::types::StorageValue)
/// * [`StorageMap`](crate::storage::types::StorageMap)
/// * [`CountedStorageMap`](crate::storage::types::CountedStorageMap)
/// * [`StorageDoubleMap`](crate::storage::types::StorageDoubleMap)
/// * [`StorageNMap`](crate::storage::types::StorageNMap)
/// * [`CountedStorageNMap`](crate::storage::types::CountedStorageNMap)
///
/// ## Storage Type Usage
///
/// The following details are relevant to all of the aforementioned storage types.
/// Depending on the exact storage type, it may require the following generic parameters:
///
/// * [`Prefix`](#prefixes) - Used to give the storage item a unique key in the underlying
/// storage.
/// * `Key` - Type of the keys used to store the values,
/// * `Value` - Type of the value being stored,
/// * [`Hasher`](#hashers) - Used to ensure the keys of a map are uniformly distributed,
/// * [`QueryKind`](#querykind) - Used to configure how to handle queries to the underlying
/// storage,
/// * `OnEmpty` - Used to handle missing values when querying the underlying storage,
/// * `MaxValues` - _not currently used_.
///
/// Each `Key` type requires its own designated `Hasher` declaration, so that
/// [`StorageDoubleMap`](frame_support::storage::types::StorageDoubleMap) needs two of
/// each, and [`StorageNMap`](frame_support::storage::types::StorageNMap) needs `N` such
/// pairs. Since [`StorageValue`](frame_support::storage::types::StorageValue) only stores
/// a single element, no configuration of hashers is needed.
///
/// ### Syntax
///
/// Two general syntaxes are supported, as demonstrated below:
///
/// 1. Named type parameters, e.g., `type Foo<T> = StorageValue<Value = u32>`.
/// 2. Positional type parameters, e.g., `type Foo<T> = StorageValue<_, u32>`.
///
/// In both instances, declaring the generic parameter `<T>` is mandatory. Optionally, it
/// can also be explicitly declared as `<T: Config>`. In the compiled code, `T` will
/// automatically include the trait bound `Config`.
///
/// Note that in positional syntax, the first generic type parameter must be `_`.
///
/// #### Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// /// Positional syntax, without bounding `T`.
/// #[pallet::storage]
/// pub type Foo<T> = StorageValue<_, u32>;
///
/// /// Positional syntax, with bounding `T`.
/// #[pallet::storage]
/// pub type Bar<T: Config> = StorageValue<_, u32>;
///
/// /// Named syntax.
/// #[pallet::storage]
/// pub type Baz<T> = StorageMap<Hasher = Blake2_128Concat, Key = u32, Value = u32>;
/// }
/// ```
///
/// ### Value Trait Bounds
///
/// To use a type as the value of a storage type, be it `StorageValue`, `StorageMap` or
/// anything else, you need to meet a number of trait bound constraints.
///
/// See: <https://paritytech.github.io/polkadot-sdk/master/polkadot_sdk_docs/reference_docs/frame_storage_derives/index.html>.
///
/// Notably, all value types need to implement `Encode`, `Decode`, `MaxEncodedLen` and
/// `TypeInfo`, and possibly `Default`, if
/// [`ValueQuery`](frame_support::storage::types::ValueQuery) is used, explained in the
/// next section.
///
/// ### QueryKind
///
/// Every storage type mentioned above has a generic type called
/// [`QueryKind`](frame_support::storage::types::QueryKindTrait) that determines its
/// "query" type. This refers to the kind of value returned when querying the storage, for
/// instance, through a `::get()` method.
///
/// There are three types of queries:
///
/// 1. [`OptionQuery`](frame_support::storage::types::OptionQuery): The default query type.
/// It returns `Some(V)` if the value is present, or `None` if it isn't, where `V` is
/// the value type.
/// 2. [`ValueQuery`](frame_support::storage::types::ValueQuery): Returns the value itself
/// if present; otherwise, it returns `Default::default()`. This behavior can be
/// adjusted with the `OnEmpty` generic parameter, which defaults to `OnEmpty =
/// GetDefault`.
/// 3. [`ResultQuery`](frame_support::storage::types::ResultQuery): Returns `Result<V, E>`,
/// where `V` is the value type.
///
/// See [`QueryKind`](frame_support::storage::types::QueryKindTrait) for further examples.
///
/// ### Optimized Appending
///
/// All storage items — such as
/// [`StorageValue`](frame_support::storage::types::StorageValue),
/// [`StorageMap`](frame_support::storage::types::StorageMap), and their variants—offer an
/// `::append()` method optimized for collections. Using this method avoids the
/// inefficiency of decoding and re-encoding entire collections when adding items. For
/// instance, consider the storage declaration `type MyVal<T> = StorageValue<_, Vec<u8>,
/// ValueQuery>`. With `MyVal` storing a large list of bytes, `::append()` lets you
/// directly add bytes to the end in storage without processing the full list. Depending on
/// the storage type, additional key specifications may be needed.
///
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_append)]
/// Similarly, there also exists a `::try_append()` method, which can be used when handling
/// types where an append operation might fail, such as a
/// [`BoundedVec`](frame_support::BoundedVec).
///
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_try_append)]
/// ### Optimized Length Decoding
///
/// All storage items — such as
/// [`StorageValue`](frame_support::storage::types::StorageValue),
/// [`StorageMap`](frame_support::storage::types::StorageMap), and their counterparts —
/// incorporate the `::decode_len()` method. This method allows for efficient retrieval of
/// a collection's length without the necessity of decoding the entire dataset.
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_decode_len)]
/// ### Hashers
///
/// For all storage types, except
/// [`StorageValue`](frame_support::storage::types::StorageValue), a set of hashers needs
/// to be specified. The choice of hashers is crucial, especially in production chains. The
/// purpose of storage hashers in maps is to ensure the keys of a map are
/// uniformly distributed. An unbalanced map/trie can lead to inefficient performance.
///
/// In general, hashers are categorized as either cryptographically secure or not. The
/// former is slower than the latter. `Blake2` and `Twox` serve as examples of each,
/// respectively.
///
/// As a rule of thumb:
///
/// 1. If the map keys are not controlled by end users, or are cryptographically secure by
/// definition (e.g., `AccountId`), then the use of cryptographically secure hashers is NOT
/// required.
/// 2. If the map keys are controllable by the end users, cryptographically secure hashers
/// should be used.
///
/// For more information, look at the types that implement
/// [`frame_support::StorageHasher`](frame_support::StorageHasher).
///
/// Lastly, it's recommended for hashers with "concat" to have reversible hashes. Refer to
/// the implementors section of
/// [`hash::ReversibleStorageHasher`](frame_support::hash::ReversibleStorageHasher).
///
/// ### Prefixes
///
/// Internally, every storage type generates a "prefix". This prefix serves as the initial
/// segment of the key utilized to store values in the on-chain state (i.e., the final key
/// used in [`sp_io::storage`](sp_io::storage)). For all storage types, the following rule
/// applies:
///
/// > The storage prefix begins with `twox128(pallet_prefix) ++ twox128(STORAGE_PREFIX)`,
/// > where
/// > `pallet_prefix` is the name assigned to the pallet instance in
/// > [`frame_support::construct_runtime`](frame_support::construct_runtime), and
/// > `STORAGE_PREFIX` is the name of the `type` aliased to a particular storage type, such
/// > as
/// > `Foo` in `type Foo<T> = StorageValue<..>`.
///
/// For [`StorageValue`](frame_support::storage::types::StorageValue), no additional key is
/// required. For map types, the prefix is extended with one or more keys defined by the
/// map.
///
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_map_prefixes)]
/// ## Related Macros
///
/// The following attribute macros can be used in conjunction with the `#[storage]` macro:
///
/// * [`macro@getter`]: Creates a custom getter function.
/// * [`macro@storage_prefix`]: Overrides the default prefix of the storage item.
/// * [`macro@unbounded`]: Declares the storage item as unbounded.
/// * [`macro@disable_try_decode_storage`]: Declares that try-runtime checks should not
/// attempt to decode the storage item.
///
/// #### Example
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// /// A kitchen-sink StorageValue, with all possible additional attributes.
/// #[pallet::storage]
/// #[pallet::getter(fn foo)]
/// #[pallet::storage_prefix = "OtherFoo"]
/// #[pallet::unbounded]
/// #[pallet::disable_try_decode_storage]
/// pub type Foo<T> = StorageValue<_, u32, ValueQuery>;
/// }
/// ```
///
/// ## Note on deprecation of storage items
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the storage item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::storage;
pub use frame_support_procedural::{
task_condition, task_index, task_list, task_weight, tasks_experimental,
};
/// Allows a pallet to declare a type as an origin.
///
/// If defined as such, this type will be amalgamated at the runtime level into
/// `RuntimeOrigin`, very similar to [`call`], [`error`] and [`event`]. See
/// [`composite_enum`] for similar cases.
///
/// Origin is a complex FRAME topics and is further explained in `polkadot_sdk_docs`.
///
/// ## Syntax Variants
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// /// On the spot declaration.
/// #[pallet::origin]
/// #[derive(PartialEq, Eq, Clone, RuntimeDebug, Encode, Decode, TypeInfo, MaxEncodedLen)]
/// pub enum Origin {
/// Foo,
/// Bar,
/// }
/// }
/// ```
///
/// Or, more commonly used:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// #[derive(PartialEq, Eq, Clone, RuntimeDebug, Encode, Decode, TypeInfo, MaxEncodedLen)]
/// pub enum RawOrigin {
/// Foo,
/// Bar,
/// }
///
/// #[pallet::origin]
/// pub type Origin = RawOrigin;
/// }
/// ```
///
/// ## Warning
///
/// Modifying any pallet's origin type will cause the runtime level origin type to also
/// change in encoding. If stored anywhere on-chain, this will require a data migration.
///
/// Read more about origins at the [Origin Reference
/// Docs](../../polkadot_sdk_docs/reference_docs/frame_origin/index.html).
pub use frame_support_procedural::origin;
}
#[deprecated(note = "Will be removed after July 2023; Use `sp_runtime::traits` directly instead.")]
pub mod error {
#[doc(hidden)]
pub use sp_runtime::traits::{BadOrigin, LookupError};
}
#[doc(inline)]
pub use frame_support_procedural::register_default_impl;
// Generate a macro that will enable/disable code based on `std` feature being active.
sp_core::generate_feature_enabled_macro!(std_enabled, feature = "std", $);
// Generate a macro that will enable/disable code based on `try-runtime` feature being active.
sp_core::generate_feature_enabled_macro!(try_runtime_enabled, feature = "try-runtime", $);
sp_core::generate_feature_enabled_macro!(try_runtime_or_std_enabled, any(feature = "try-runtime", feature = "std"), $);
sp_core::generate_feature_enabled_macro!(try_runtime_and_std_not_enabled, all(not(feature = "try-runtime"), not(feature = "std")), $);
// Helper for implementing GenesisBuilder runtime API
pub mod genesis_builder_helper;
#[cfg(test)]
mod test {
// use super::*;
use crate::{
hash::*,
storage::types::{StorageMap, StorageValue, ValueQuery},
traits::{ConstU32, StorageInstance},
BoundedVec,
};
use sp_io::{hashing::twox_128, TestExternalities};
struct Prefix;
impl StorageInstance for Prefix {
fn pallet_prefix() -> &'static str {
"test"
}
const STORAGE_PREFIX: &'static str = "foo";
}
struct Prefix1;
impl StorageInstance for Prefix1 {
fn pallet_prefix() -> &'static str {
"test"
}
const STORAGE_PREFIX: &'static str = "MyVal";
}
struct Prefix2;
impl StorageInstance for Prefix2 {
fn pallet_prefix() -> &'static str {
"test"
}
const STORAGE_PREFIX: &'static str = "MyMap";
}
#[docify::export]
#[test]
pub fn example_storage_value_try_append() {
type MyVal = StorageValue<Prefix, BoundedVec<u8, ConstU32<10>>, ValueQuery>;
TestExternalities::default().execute_with(|| {
MyVal::set(BoundedVec::try_from(vec![42, 43]).unwrap());
assert_eq!(MyVal::get(), vec![42, 43]);
// Try to append a single u32 to BoundedVec stored in `MyVal`
assert_ok!(MyVal::try_append(40));
assert_eq!(MyVal::get(), vec![42, 43, 40]);
});
}
#[docify::export]
#[test]
pub fn example_storage_value_append() {
type MyVal = StorageValue<Prefix, Vec<u8>, ValueQuery>;
TestExternalities::default().execute_with(|| {
MyVal::set(vec![42, 43]);
assert_eq!(MyVal::get(), vec![42, 43]);
// Append a single u32 to Vec stored in `MyVal`
MyVal::append(40);
assert_eq!(MyVal::get(), vec![42, 43, 40]);
});
}
#[docify::export]
#[test]
pub fn example_storage_value_decode_len() {
type MyVal = StorageValue<Prefix, BoundedVec<u8, ConstU32<10>>, ValueQuery>;
TestExternalities::default().execute_with(|| {
MyVal::set(BoundedVec::try_from(vec![42, 43]).unwrap());
assert_eq!(MyVal::decode_len().unwrap(), 2);
});
}
#[docify::export]
#[test]
pub fn example_storage_value_map_prefixes() {
type MyVal = StorageValue<Prefix1, u32, ValueQuery>;
type MyMap = StorageMap<Prefix2, Blake2_128Concat, u16, u32, ValueQuery>;
TestExternalities::default().execute_with(|| {
// This example assumes `pallet_prefix` to be "test"
// Get storage key for `MyVal` StorageValue
assert_eq!(
MyVal::hashed_key().to_vec(),
[twox_128(b"test"), twox_128(b"MyVal")].concat()
);
// Get storage key for `MyMap` StorageMap and `key` = 1
let mut k: Vec<u8> = vec![];
k.extend(&twox_128(b"test"));
k.extend(&twox_128(b"MyMap"));
k.extend(&1u16.blake2_128_concat());
assert_eq!(MyMap::hashed_key_for(1).to_vec(), k);
});
}
}