[BOUNTY #800] View facade register/deregister with events and stability tests

contracts/view-facade/README.md

@@ -92,6 +92,28 @@ Emitted once when `init` succeeds.
 
 **Topic:** `("facade", "init")`
 
+### `Register`
+
+Emitted when a contract is added to the registry via `register`.
+
+| Field | Type | Description |
+|---|---|---|
+| `address` | `Address` | On-chain address of the registered contract |
+| `kind` | `ContractKind` | Role of the contract |
+| `version` | `u32` | Version number at registration time |
+
+**Topic:** `("facade", "register")`
+
+### `Deregister`
+
+Emitted when a contract is removed from the registry via `deregister`.
+
+| Field | Type | Description |
+|---|---|---|
+| `address` | `Address` | On-chain address of the removed contract |
+
+**Topic:** `("facade", "deregstr")`
+
 ## Error Codes
 
 | Code | Value | Meaning |
@@ -117,10 +139,11 @@ cargo test
 Expected output:
 
 ```
-running 14 tests
+running 17 tests
 test test::test_contract_count_initially_zero ... ok
 test test::test_deregister_before_init_rejected ... ok
 test test::test_deregister_contract ... ok
+test test::test_deregister_emits_event ... ok
 test test::test_deregister_nonexistent_is_noop ... ok
 test test::test_double_init_rejected ... ok
 test test::test_get_admin_before_init_returns_none ... ok
@@ -132,8 +155,10 @@ test test::test_list_and_count_contracts ... ok
 test test::test_register_all_contract_kinds ... ok
 test test::test_register_and_lookup_contract ... ok
 test test::test_register_before_init_rejected ... ok
+test test::test_register_deregister_stability ... ok
+test test::test_register_emits_event ... ok
 
-test result: ok. 14 passed; 0 failed; 0 ignored
+test result: ok. 17 passed; 0 failed; 0 ignored
 ```
 
 ## Building

contracts/view-facade/src/lib.rs

@@ -268,13 +268,19 @@ impl ViewFacade {
             .unwrap_or(Vec::new(&env));
 
         registry.push_back(RegisteredContract {
-            address,
-            kind,
+            address: address.clone(),
+            kind: kind.clone(),
             version,
         });
 
         env.storage().instance().set(&DataKey::Registry, &registry);
 
+        // Emit register event for off-chain indexers
+        env.events().publish(
+            (symbol_short!("facade"), symbol_short!("register")),
+            (address, kind, version),
+        );
+
         Ok(())
     }
 
@@ -316,6 +322,12 @@ impl ViewFacade {
 
         env.storage().instance().set(&DataKey::Registry, &updated);
 
+        // Emit deregister event for off-chain indexers
+        env.events().publish(
+            (symbol_short!("facade"), symbol_short!("deregstr")),
+            address,
+        );
+
         Ok(())
     }
 

contracts/view-facade/src/test.rs

@@ -275,3 +275,106 @@ fn test_deregister_before_init_rejected() {
     let result = facade.try_deregister(&addr);
     assert_eq!(result, Err(Ok(FacadeError::NotInitialized)));
 }
+
+// ---------------------------------------------------------------------------
+// Registry — events
+// ---------------------------------------------------------------------------
+
+/// `register` emits a `("facade", "register")` event with (address, kind, version).
+#[test]
+fn test_register_emits_event() {
+    use soroban_sdk::{symbol_short, testutils::Events as _, vec, IntoVal};
+
+    let (env, facade, admin) = setup();
+    let contract = Address::generate(&env);
+
+    facade.init(&admin);
+    facade.register(&contract, &ContractKind::BountyEscrow, &1u32);
+
+    let facade_id = facade.address.clone();
+    let events = env.events().all();
+
+    let found = events.iter().any(|(cid, topics, _data)| {
+        if cid != facade_id {
+            return false;
+        }
+        let expected = vec![
+            &env,
+            symbol_short!("facade").into_val(&env),
+            symbol_short!("register").into_val(&env),
+        ];
+        topics == expected
+    });
+
+    assert!(found, "register event must be emitted");
+}
+
+/// `deregister` emits a `("facade", "deregstr")` event with the removed address.
+#[test]
+fn test_deregister_emits_event() {
+    use soroban_sdk::{symbol_short, testutils::Events as _, vec, IntoVal};
+
+    let (env, facade, admin) = setup();
+    let contract = Address::generate(&env);
+
+    facade.init(&admin);
+    facade.register(&contract, &ContractKind::SorobanEscrow, &2u32);
+    facade.deregister(&contract);
+
+    let facade_id = facade.address.clone();
+    let events = env.events().all();
+
+    let found = events.iter().any(|(cid, topics, _data)| {
+        if cid != facade_id {
+            return false;
+        }
+        let expected = vec![
+            &env,
+            symbol_short!("facade").into_val(&env),
+            symbol_short!("deregstr").into_val(&env),
+        ];
+        topics == expected
+    });
+
+    assert!(found, "deregister event must be emitted");
+}
+
+// ---------------------------------------------------------------------------
+// Registry — stability
+// ---------------------------------------------------------------------------
+
+/// Registering and deregistering multiple contracts leaves the registry in
+/// a consistent state — only the expected entries remain.
+#[test]
+fn test_register_deregister_stability() {
+    let (env, facade, admin) = setup();
+
+    facade.init(&admin);
+
+    let c1 = Address::generate(&env);
+    let c2 = Address::generate(&env);
+    let c3 = Address::generate(&env);
+
+    facade.register(&c1, &ContractKind::BountyEscrow, &1);
+    facade.register(&c2, &ContractKind::ProgramEscrow, &2);
+    facade.register(&c3, &ContractKind::GrainlifyCore, &3);
+    assert_eq!(facade.contract_count(), 3);
+
+    // Remove the middle one
+    facade.deregister(&c2);
+    assert_eq!(facade.contract_count(), 2);
+
+    // c1 and c3 should remain in order
+    let list = facade.list_contracts();
+    assert_eq!(list.get(0).unwrap().address, c1);
+    assert_eq!(list.get(1).unwrap().address, c3);
+
+    // c2 should be gone
+    assert_eq!(facade.get_contract(&c2), None);
+
+    // Re-register c2 — should appear at end
+    facade.register(&c2, &ContractKind::ProgramEscrow, &4);
+    assert_eq!(facade.contract_count(), 3);
+    assert_eq!(facade.list_contracts().get(2).unwrap().address, c2);
+    assert_eq!(facade.list_contracts().get(2).unwrap().version, 4);
+}