Add must_pay_many

src/lib.rs

@@ -25,7 +25,7 @@ pub use parse_reply::{
     parse_reply_instantiate_data, MsgExecuteContractResponse, MsgInstantiateContractResponse,
     ParseReplyError,
 };
-pub use payment::{may_pay, must_pay, nonpayable, one_coin, PaymentError};
+pub use payment::{may_pay, must_pay, must_pay_many, nonpayable, one_coin, PaymentError};
 pub use threshold::{Threshold, ThresholdError, ThresholdResponse};
 
 pub use crate::balance::NativeBalance;

src/payment.rs

@@ -1,4 +1,5 @@
 use cosmwasm_std::{Coin, MessageInfo, Uint128};
+use std::collections::HashMap;
 use thiserror::Error;
 
 /// returns an error if any coins were sent
@@ -52,6 +53,39 @@ pub fn may_pay(info: &MessageInfo, denom: &str) -> Result<Uint128, PaymentError>
     }
 }
 
+pub fn must_pay_many(
+    info: &MessageInfo,
+    required_denoms: &[&str],
+) -> Result<Vec<Coin>, PaymentError> {
+    if info.funds.is_empty() {
+        return Err(PaymentError::NoFunds {});
+    }
+    if info.funds.len() != required_denoms.len() {
+        return Err(PaymentError::IncorrectNumberOfDenoms(required_denoms.len()));
+    }
+
+    let mut funds_map = HashMap::new();
+    for coin in &info.funds {
+        if funds_map.insert(coin.denom.as_str(), coin).is_some() {
+            return Err(PaymentError::DuplicateDenom(coin.denom.clone()));
+        }
+    }
+
+    let mut matched_coins: Vec<Coin> = Vec::new();
+    for &denom in required_denoms {
+        match funds_map.get(denom) {
+            Some(coin) => {
+                if coin.amount == Uint128::zero() {
+                    return Err(PaymentError::ZeroAmountDenom(denom.to_string()));
+                }
+                matched_coins.push((**coin).clone());
+            }
+            None => return Err(PaymentError::MissingDenom(denom.to_string())),
+        }
+    }
+    Ok(matched_coins)
+}
+
 #[derive(Error, Debug, PartialEq, Eq)]
 pub enum PaymentError {
     #[error("Must send reserve token '{0}'")]
@@ -68,6 +102,15 @@ pub enum PaymentError {
 
     #[error("This message does no accept funds")]
     NonPayable {},
+
+    #[error("Must send '{0}' denoms")]
+    IncorrectNumberOfDenoms(usize),
+
+    #[error("Zero amound sent for '{0}'")]
+    ZeroAmountDenom(String),
+
+    #[error("Received duplicate denom '{0}'")]
+    DuplicateDenom(String),
 }
 
 #[cfg(test)]
@@ -108,6 +151,36 @@ mod test {
         let err = may_pay(&mixed_payment, atom).unwrap_err();
         assert_eq!(err, PaymentError::ExtraDenom("wei".to_string()));
     }
+    #[test]
+    fn test_must_pay_many_works() {
+        let atom: &str = "uatom";
+        let eth: &str = "wei";
+
+        let no_payment = mock_info(SENDER, &[]);
+        let atom_payment = mock_info(SENDER, &coins(100, atom));
+        let zero_amount_payment = mock_info(SENDER, &[coin(0, atom), coin(120, eth)]);
+        let duplicate_atom_payment = mock_info(SENDER, &[coin(50, atom), coin(120, atom)]);
+        let eth_payment = mock_info(SENDER, &coins(100, eth));
+        let mixed_payment = mock_info(SENDER, &[coin(50, atom), coin(120, eth)]);
+
+        let err = must_pay_many(&no_payment, &[atom, eth]).unwrap_err();
+        assert_eq!(err, PaymentError::NoFunds {});
+
+        let err = must_pay_many(&atom_payment, &[atom, eth]).unwrap_err();
+        assert_eq!(err, PaymentError::IncorrectNumberOfDenoms(2));
+
+        let err = must_pay_many(&duplicate_atom_payment, &[atom, eth]).unwrap_err();
+        assert_eq!(err, PaymentError::DuplicateDenom(atom.to_string()));
+
+        let err = must_pay_many(&zero_amount_payment, &[atom, eth]).unwrap_err();
+        assert_eq!(err, PaymentError::ZeroAmountDenom(atom.to_string()));
+
+        let err = must_pay_many(&eth_payment, &[atom]).unwrap_err();
+        assert_eq!(err, PaymentError::MissingDenom(atom.to_string()));
+
+        let res = must_pay_many(&mixed_payment, &[atom, eth]).unwrap();
+        assert_eq!(res, vec![coin(50, atom), coin(120, eth)]);
+    }
 
     #[test]
     fn must_pay_works() {