Merge pull request #5127 from mnaamani/prevent-amm-buy-sell-while-rev…

…enue-split

Amm buy/sell operations not allowed during revenue split

runtime-modules/project-token/src/lib.rs

@@ -890,6 +890,7 @@ decl_module! {
         /// - user usable JOY balance must be enough for buying (+ existential deposit)
         /// - slippage tolerance constraints respected if provided
         /// - token total supply and amount value must be s.t. `eval` function doesn't overflow
+        /// - token supply can be modified (there is no active revenue split)
         ///
         /// Postconditions
         /// - `amount` CRT minted into account (which is created if necessary with existential deposit transferred to it)
@@ -911,6 +912,8 @@ decl_module! {
             )?;
 
             let token_data = Self::ensure_token_exists(token_id)?;
+            token_data.ensure_can_modify_supply::<T>()?;
+
             let curve = token_data.amm_curve.ok_or(Error::<T>::NotInAmmState)?;
 
             let user_account_data_exists = AccountInfoByTokenAndMember::<T>::contains_key(token_id, member_id);
@@ -975,6 +978,7 @@ decl_module! {
         /// - slippage tolerance constraints respected if provided
         /// - token total supply and amount value must be s.t. `eval` function doesn't overflow
         /// - amm treasury account must have sufficient JOYs for the operation
+        /// - token supply can be modified (there is no active revenue split)
         ///
         /// Postconditions
         /// - `amount` burned from user account
@@ -997,6 +1001,8 @@ decl_module! {
             )?;
 
             let token_data = Self::ensure_token_exists(token_id)?;
+            token_data.ensure_can_modify_supply::<T>()?;
+
             let curve = token_data.amm_curve.ok_or(Error::<T>::NotInAmmState)?;
             let user_acc_data = Self::ensure_account_data_exists(token_id, &member_id)?;
 

runtime-modules/project-token/src/tests/amm.rs

@@ -151,6 +151,34 @@ fn amm_buy_succeeds_with_existing_user() {
     })
 }
 
+#[test]
+fn amm_buy_fails_with_revenue_split() {
+    let (user_member_id, user_account_id) = member!(1);
+    build_default_test_externalities_with_balances(vec![(
+        user_account_id,
+        DEFAULT_SPLIT_REVENUE
+            + amm_function_buy_values_with_tx_fees(DEFAULT_AMM_BUY_AMOUNT, Zero::zero())
+            + ed(),
+    )])
+    .execute_with(|| {
+        IssueTokenFixture::default().execute_call().unwrap();
+        ActivateAmmFixture::default().execute_call().unwrap();
+
+        IssueRevenueSplitFixture::default().execute_call().unwrap();
+
+        let result = AmmBuyFixture::default()
+            .with_sender(user_account_id)
+            .with_amount(DEFAULT_AMM_BUY_AMOUNT)
+            .with_member_id(user_member_id)
+            .execute_call();
+
+        assert_err!(
+            result,
+            Error::<Test>::CannotModifySupplyWhenRevenueSplitsAreActive
+        );
+    })
+}
+
 #[test]
 fn amm_buy_failed_with_slippage_constraint_violated() {
     let slippage_tolerance = (Permill::zero(), Balance::zero());
@@ -875,6 +903,29 @@ fn amm_sell_ok_with_event_deposited() {
     })
 }
 
+#[test]
+fn amm_sell_fails_with_revenue_split() {
+    build_default_test_externalities_with_balances(vec![(
+        member!(1).1,
+        DEFAULT_AMM_BUY_AMOUNT + DEFAULT_SPLIT_REVENUE + ExistentialDeposit::get(),
+    )])
+    .execute_with(|| {
+        IssueTokenFixture::default().execute_call().unwrap();
+        TransferFixture::default().execute_call().unwrap();
+        IssueRevenueSplitFixture::default().execute_call().unwrap();
+        ActivateAmmFixture::default().execute_call().unwrap();
+
+        let result = AmmSellFixture::default()
+            .with_amount(DEFAULT_AMM_BUY_AMOUNT)
+            .execute_call();
+
+        assert_err!(
+            result,
+            Error::<Test>::CannotModifySupplyWhenRevenueSplitsAreActive
+        );
+    })
+}
+
 // ------------------- DEACTIVATE ---------------------------------------
 
 #[test]