change div to checked_div method

pallets/channel-commission/src/mock.rs

@@ -32,9 +32,7 @@ use frame_support::{
 };
 use frame_system::EnsureSignedBy;
 use sp_core::ConstU32;
-use sp_runtime::traits::Scale;
 use sp_runtime::{traits::AccountIdConversion, AccountId32, BuildStorage, DispatchError};
-use std::ops::Div;
 
 pub type BlockNumber = u64;
 pub type Amount = i128;
@@ -185,7 +183,7 @@ impl VtokenMintingInterface<AccountId, CurrencyId, Balance> for SimpleVtokenMint
 		_vtoken_id: CurrencyId,
 		token_amount: Balance,
 	) -> Result<Balance, DispatchError> {
-		Ok(token_amount.div(2u64))
+		Ok(token_amount.checked_div(2u64).unwrap())
 	}
 
 	fn get_currency_amount_by_v_currency_amount(