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// Copyright 2019-2025 PureStake Inc.
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// This file is part of Moonbeam.
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// Moonbeam is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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// Moonbeam is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with Moonbeam.  If not, see <http://www.gnu.org/licenses/>.
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use sp_std::vec::Vec;
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use xcm::latest::prelude::*;
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use xcm_executor::traits::DropAssets;
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/// Morph a given `DropAssets` implementation into one which filter out erc20 assets.
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pub struct AssetTrapWrapper<AssetTrap, T>(core::marker::PhantomData<(AssetTrap, T)>);
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// Morph a given `DropAssets` implementation into one which filter out erc20 assets.
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impl<AssetTrap: DropAssets, T: crate::Config> DropAssets for AssetTrapWrapper<AssetTrap, T> {
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	fn drop_assets(
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		origin: &xcm::latest::Location,
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		mut assets: xcm_executor::AssetsInHolding,
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		context: &XcmContext,
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	) -> xcm::latest::Weight {
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		// Remove all erc20 assets
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		let assets_to_remove: Vec<_> = assets
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			.fungible_assets_iter()
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			.filter_map(|multiasset| {
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				crate::Pallet::<T>::is_erc20_asset(&multiasset).then_some(multiasset.id)
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			})
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			.collect();
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		for id in assets_to_remove {
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			assets.saturating_take(xcm::latest::AssetFilter::Wild(
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				xcm::latest::WildAsset::AllOf {
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					fun: WildFungible,
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					id,
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				},
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			));
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		}
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		AssetTrap::drop_assets(origin, assets, context)
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	}
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}