feat: add transfer_batch — send tokens to multiple recipients in one call

veritixpay/contract/token/src/batch.rs

@@ -0,0 +1,28 @@
+use crate::balance::{receive_balance, spend_balance};
+use crate::validation::require_positive_amount;
+use soroban_sdk::{contracttype, symbol_short, Address, Env, Vec};
+
+/// Represents a single entry in a batch transfer.
+#[contracttype]
+#[derive(Clone)]
+pub struct BatchEntry {
+    pub address: Address,
+    pub amount: i128,
+}
+
+/// Transfers tokens from `from` to multiple recipients in one call.
+/// Maximum 50 recipients per batch.
+pub fn transfer_batch(e: &Env, from: Address, recipients: Vec<BatchEntry>) {
+    from.require_auth();
+    if recipients.len() > 50 {
+        panic!("BatchLimit: maximum 50 recipients per call");
+    }
+    let mut total: i128 = 0;
+    for entry in recipients.iter() {
+        require_positive_amount(entry.amount);
+        spend_balance(e, from.clone(), entry.amount);
+        receive_balance(e, entry.address.clone(), entry.amount);
+        total = total.checked_add(entry.amount).expect("overflow");
+    }
+    e.events().publish((symbol_short!("batch_xfer"), from), total);
+}

veritixpay/contract/token/src/batch_test.rs

@@ -0,0 +1,43 @@
+use soroban_sdk::{testutils::Address as _, Address, Env, Vec};
+use crate::balance::read_balance;
+use crate::batch::{transfer_batch, BatchEntry};
+use crate::contract::VeritixToken;
+
+fn setup_env() -> Env { let e = Env::default(); e.mock_all_auths(); e }
+
+#[test]
+fn test_transfer_batch_distributes_correctly() {
+    let e = setup_env();
+    let cid = e.register_contract(None, VeritixToken);
+    let from = Address::generate(&e);
+    let r1 = Address::generate(&e);
+    let r2 = Address::generate(&e);
+
+    e.as_contract(&cid, || {
+        crate::balance::receive_balance(&e, from.clone(), 1000);
+        let mut recs: Vec<BatchEntry> = Vec::new(&e);
+        recs.push_back(BatchEntry { address: r1.clone(), amount: 400 });
+        recs.push_back(BatchEntry { address: r2.clone(), amount: 600 });
+        transfer_batch(&e, from.clone(), recs);
+        assert_eq!(read_balance(&e, r1.clone()), 400);
+        assert_eq!(read_balance(&e, r2.clone()), 600);
+        assert_eq!(read_balance(&e, from.clone()), 0);
+    });
+}
+
+#[test]
+#[should_panic(expected = "BatchLimit")]
+fn test_transfer_batch_rejects_over_50() {
+    let e = setup_env();
+    let cid = e.register_contract(None, VeritixToken);
+    let from = Address::generate(&e);
+
+    e.as_contract(&cid, || {
+        crate::balance::receive_balance(&e, from.clone(), 100_000);
+        let mut recs: Vec<BatchEntry> = Vec::new(&e);
+        for _ in 0..51 {
+            recs.push_back(BatchEntry { address: Address::generate(&e), amount: 1 });
+        }
+        transfer_batch(&e, from.clone(), recs);
+    });
+}

veritixpay/contract/token/src/lib.rs

@@ -16,6 +16,7 @@ pub mod splitter;
 pub mod storage_types;
 pub mod validation;
 
+pub mod batch;
 mod contract;
 
 #[cfg(test)]
@@ -39,6 +40,9 @@ mod admin_test;
 #[cfg(test)]
 mod splitter_test;
 
+#[cfg(test)]
+mod batch_test;
+
 #[cfg(test)]
 mod dispute_test;