refactor: drop the new_account parameter and derive the destination f…

…rom the signer

docs/architecture/0024-twin-ownership-transfer.md

@@ -21,8 +21,8 @@ Introduce a two-step, time-bound transfer protocol implemented in `pallet-tfgrid
 
 ### Dispatchables
 
-- `request_twin_transfer(origin=new_account, twin_id, new_account)`
-  - Origin must match `new_account`.
+- `request_twin_transfer(origin=new_account, twin_id)`
+  - Origin is the prospective new account.
   - Validates preconditions and creates a pending transfer with expiry.
   - Emits `TwinTransferRequested { twin_id, old_account, new_account }`.
 

docs/misc/twin_transfer.md

@@ -4,14 +4,14 @@ This document explains the twin ownership transfer flow in the `pallet-tfgrid` p
 
 ## Overview
 
-- The new owner initiates the transfer via `request_twin_transfer(twin_id, new_account)`.
+- The new owner initiates the transfer via `request_twin_transfer(twin_id)`.
 - The current owner accepts via `accept_twin_transfer(request_id)`.
 - On success, ownership of the twin moves to the new account, reserved balances are repatriated, and indices are updated.
 
 ## Dispatchables
 
-- request_twin_transfer(origin, twin_id, new_account)
-  - Origin must be the new account.
+- request_twin_transfer(origin, twin_id)
+  - Origin (signer) is the new account.
   - Emits `TwinTransferRequested { twin_id, old_account, new_account }`.
 - accept_twin_transfer(origin, request_id)
   - Origin must be the current (old) owner of the twin.
@@ -28,7 +28,6 @@ This document explains the twin ownership transfer flow in the `pallet-tfgrid` p
 ## Common Errors
 
 - UserDidNotSignTermsAndConditions: new account did not accept T&C.
-- TwinTransferRequestMustBeFromNewAccount: request must be signed by the new account.
 - TwinTransferNewAccountHasTwin: new account already has a twin.
 - TwinTransferPendingExists: a pending transfer already exists for this twin.
 - TwinTransferRequestNotFound: request ID does not exist.

substrate-node/pallets/pallet-tfgrid/src/lib.rs

@@ -624,7 +624,6 @@ pub mod pallet {
         TwinTransferRequestAlreadyCompleted,
         TwinTransferNewAccountHasTwin,
         TwinTransferPendingExists,
-        TwinTransferRequestMustBeFromNewAccount,
     }
 
     #[pallet::genesis_config]
@@ -1296,9 +1295,8 @@ pub mod pallet {
         pub fn request_twin_transfer(
             origin: OriginFor<T>,
             twin_id: u32,
-            new_account: T::AccountId,
         ) -> DispatchResultWithPostInfo {
-            Self::_request_twin_transfer(origin, twin_id, new_account)
+            Self::_request_twin_transfer(origin, twin_id)
         }
 
         // Twin ownership transfer: accept by current owner

substrate-node/pallets/pallet-tfgrid/src/tests.rs

@@ -42,7 +42,6 @@ fn twin_transfer_request_happy_path() {
         assert_ok!(TfgridModule::_request_twin_transfer(
             RuntimeOrigin::signed(bob()),
             1,
-            bob(),
         ));
 
         // storage checks
@@ -56,23 +55,7 @@ fn twin_transfer_request_happy_path() {
     });
 }
 
-#[test]
-fn twin_transfer_request_wrong_initiator_fails() {
-    ExternalityBuilder::build().execute_with(|| {
-        create_twin();
-        assert_ok!(TfgridModule::user_accept_tc(
-            RuntimeOrigin::signed(bob()),
-            get_document_link_input(b"some_link"),
-            get_document_hash_input(b"some_hash"),
-        ));
-
-        // alice cannot initiate a request for bob
-        assert_noop!(
-            TfgridModule::_request_twin_transfer(RuntimeOrigin::signed(alice()), 1, bob()),
-            Error::<TestRuntime>::TwinTransferRequestMustBeFromNewAccount
-        );
-    });
-}
+// Note: request must be initiated by the new account (signer). No test needed for mismatched initiator.
 
 #[test]
 fn twin_transfer_request_without_tc_fails() {
@@ -83,7 +66,7 @@ fn twin_transfer_request_without_tc_fails() {
         // When: bob (new prospective owner) did NOT accept T&C and tries to request transfer
         // Then: it should fail with UserDidNotSignTermsAndConditions
         assert_noop!(
-            TfgridModule::_request_twin_transfer(RuntimeOrigin::signed(bob()), 1, bob()),
+            TfgridModule::_request_twin_transfer(RuntimeOrigin::signed(bob()), 1),
             Error::<TestRuntime>::UserDidNotSignTermsAndConditions
         );
     });
@@ -96,7 +79,7 @@ fn twin_transfer_request_new_account_has_twin_fails() {
         create_twin_bob(); // bob already has a twin
 
         assert_noop!(
-            TfgridModule::_request_twin_transfer(RuntimeOrigin::signed(bob()), 1, bob()),
+            TfgridModule::_request_twin_transfer(RuntimeOrigin::signed(bob()), 1),
             Error::<TestRuntime>::TwinTransferNewAccountHasTwin
         );
     });
@@ -114,12 +97,11 @@ fn twin_transfer_request_duplicate_pending_fails() {
         assert_ok!(TfgridModule::_request_twin_transfer(
             RuntimeOrigin::signed(bob()),
             1,
-            bob(),
         ));
 
         // second request while pending should fail
         assert_noop!(
-            TfgridModule::_request_twin_transfer(RuntimeOrigin::signed(bob()), 1, bob()),
+            TfgridModule::_request_twin_transfer(RuntimeOrigin::signed(bob()), 1),
             Error::<TestRuntime>::TwinTransferPendingExists
         );
     });
@@ -139,7 +121,6 @@ fn twin_transfer_accept_happy_path_moves_reserved_and_updates_owner() {
         assert_ok!(TfgridModule::_request_twin_transfer(
             RuntimeOrigin::signed(bob()),
             1,
-            bob(),
         ));
 
         // reserve some balance on alice
@@ -183,7 +164,6 @@ fn twin_transfer_accept_expired_fails() {
         assert_ok!(TfgridModule::_request_twin_transfer(
             RuntimeOrigin::signed(bob()),
             1,
-            bob(),
         ));
 
         // move block number beyond expiry
@@ -209,7 +189,6 @@ fn twin_transfer_accept_wrong_signer_fails() {
         assert_ok!(TfgridModule::_request_twin_transfer(
             RuntimeOrigin::signed(bob()),
             1,
-            bob(),
         ));
 
         // bob (new account) cannot accept; must be current owner (alice)

substrate-node/pallets/pallet-tfgrid/src/twin_transfer.rs

@@ -10,14 +10,9 @@ impl<T: Config> Pallet<T> {
     pub fn _request_twin_transfer(
         origin: T::RuntimeOrigin,
         twin_id: u32,
-        new_account: T::AccountId,
     ) -> DispatchResultWithPostInfo {
-        let requester = ensure_signed(origin)?;
-        // Request must be initiated by the new account
-        ensure!(
-            requester == new_account,
-            Error::<T>::TwinTransferRequestMustBeFromNewAccount
-        );
+        // Derive the new account directly from the signer
+        let new_account = ensure_signed(origin)?;
 
         // Twin must exist
         let twin = Twins::<T>::get(&twin_id).ok_or(Error::<T>::TwinNotExists)?;