frame_support/storage/
weak_bounded_vec.rs

1// This file is part of Substrate.
2
3// Copyright (C) Parity Technologies (UK) Ltd.
4// SPDX-License-Identifier: Apache-2.0
5
6// Licensed under the Apache License, Version 2.0 (the "License");
7// you may not use this file except in compliance with the License.
8// You may obtain a copy of the License at
9//
10// 	http://www.apache.org/licenses/LICENSE-2.0
11//
12// Unless required by applicable law or agreed to in writing, software
13// distributed under the License is distributed on an "AS IS" BASIS,
14// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15// See the License for the specific language governing permissions and
16// limitations under the License.
17
18//! Traits, types and structs to support putting a bounded vector into storage, as a raw value, map
19//! or a double map.
20
21use crate::{
22	storage::{StorageDecodeLength, StorageTryAppend},
23	traits::Get,
24};
25pub use sp_runtime::WeakBoundedVec;
26
27impl<T, S> StorageDecodeLength for WeakBoundedVec<T, S> {}
28
29impl<T, S: Get<u32>> StorageTryAppend<T> for WeakBoundedVec<T, S> {
30	fn bound() -> usize {
31		S::get() as usize
32	}
33}
34
35#[cfg(test)]
36pub mod test {
37	use super::*;
38	use crate::Twox128;
39	use frame_support::traits::ConstU32;
40	use sp_io::TestExternalities;
41
42	#[crate::storage_alias]
43	type Foo = StorageValue<Prefix, WeakBoundedVec<u32, ConstU32<7>>>;
44	#[crate::storage_alias]
45	type FooMap = StorageMap<Prefix, Twox128, u32, WeakBoundedVec<u32, ConstU32<7>>>;
46	#[crate::storage_alias]
47	type FooDoubleMap =
48		StorageDoubleMap<Prefix, Twox128, u32, Twox128, u32, WeakBoundedVec<u32, ConstU32<7>>>;
49
50	#[test]
51	fn decode_len_works() {
52		TestExternalities::default().execute_with(|| {
53			let bounded: WeakBoundedVec<u32, ConstU32<7>> = vec![1, 2, 3].try_into().unwrap();
54			Foo::put(bounded);
55			assert_eq!(Foo::decode_len().unwrap(), 3);
56		});
57
58		TestExternalities::default().execute_with(|| {
59			let bounded: WeakBoundedVec<u32, ConstU32<7>> = vec![1, 2, 3].try_into().unwrap();
60			FooMap::insert(1, bounded);
61			assert_eq!(FooMap::decode_len(1).unwrap(), 3);
62			assert!(FooMap::decode_len(0).is_none());
63			assert!(FooMap::decode_len(2).is_none());
64		});
65
66		TestExternalities::default().execute_with(|| {
67			let bounded: WeakBoundedVec<u32, ConstU32<7>> = vec![1, 2, 3].try_into().unwrap();
68			FooDoubleMap::insert(1, 1, bounded);
69			assert_eq!(FooDoubleMap::decode_len(1, 1).unwrap(), 3);
70			assert!(FooDoubleMap::decode_len(2, 1).is_none());
71			assert!(FooDoubleMap::decode_len(1, 2).is_none());
72			assert!(FooDoubleMap::decode_len(2, 2).is_none());
73		});
74	}
75}