remove zero Balance or empty NFTGallery

integration-tests/account/remove_zero_balance.exp

@@ -0,0 +1,9 @@
+processed 3 tasks
+
+task 2 'run'. lines 5-24:
+{
+  "gas_used": 0,
+  "status": {
+    "Discard": 14
+  }
+}

integration-tests/account/remove_zero_balance.move

@@ -0,0 +1,24 @@
+//# init -n dev
+
+//# faucet --addr alice --amount 0
+
+//# run --signers alice
+script {
+    use StarcoinFramework::STC::{STC};
+    use StarcoinFramework::Signer;
+    use StarcoinFramework::Account;
+    use StarcoinFramework::Token;
+
+    fun main(account: signer) {
+        let addr: address = Signer::address_of(&account);
+
+        let coin = Token::zero<STC>();
+        Account::deposit_to_self<STC>(&account, coin);
+
+        Account::remove_zero_balance<STC>(&account);
+
+        Account::set_auto_accept_token(&account, false);
+        assert!(!Account::is_accept_token<STC>(addr), 101);
+    }
+}
+// check: EXECUTED

integration-tests/nft/test_gallery.exp

@@ -1,4 +1,4 @@
-processed 16 tasks
+processed 17 tasks
 
 task 4 'run'. lines 70-78:
 {
@@ -95,3 +95,21 @@ task 15 'run'. lines 236-250:
     "Keep": "Executed"
   }
 }
+
+task 16 'run'. lines 252-269:
+{
+  "gas_used": 519398,
+  "status": {
+    "Keep": {
+      "MoveAbort": [
+        {
+          "Module": {
+            "address": "0x00000000000000000000000000000001",
+            "name": "Vector"
+          }
+        },
+        3
+      ]
+    }
+  }
+}

integration-tests/nft/test_gallery.move

@@ -247,4 +247,23 @@ fun main(sender: signer) {
 }
 }
 
+// check: EXECUTED
+
+//# run --signers bob
+script {
+    use creator::AnyNFT::{AnyNFT, AnyNFTBody};
+    use StarcoinFramework::NFTGallery;
+    use StarcoinFramework::Signer;
+
+    fun main(sender: signer) {
+        let addr: address = Signer::address_of(&sender);
+
+        NFTGallery::accept<AnyNFT, AnyNFTBody>(&sender);
+        assert!(NFTGallery::is_accept<AnyNFT, AnyNFTBody>(addr), 1);
+
+        NFTGallery::remove_empty_gallery<AnyNFT, AnyNFTBody>(&sender);
+        assert!(!NFTGallery::is_accept<AnyNFT, AnyNFTBody>(addr), 2);
+    }
+}
+
 // check: EXECUTED

sources/Account.move

@@ -993,6 +993,18 @@ module Account {
         aborts_if txn_gas_price * (txn_max_gas_units - gas_units_remaining) > 0 &&
                 global<TransactionFee::TransactionFee<TokenType>>(CoreAddresses::GENESIS_ADDRESS()).fee.value + txn_gas_price * (txn_max_gas_units - gas_units_remaining) > max_u128();
     }
+
+    /// Remove zero Balance
+    public fun remove_zero_balance<TokenType: store>(account: &signer) acquires Balance {
+        let addr: address = Signer::address_of(account);
+        let Balance<TokenType> { token } = move_from<Balance<TokenType>>(addr);
+        Token::destroy_zero<TokenType>(token);
+    }
+
+    spec remove_zero_balance {
+        let addr = Signer::address_of(account);
+        aborts_if !exists<Balance<CoinType>>(addr);
+    }
 }
 
 }

sources/AccountScripts.move

@@ -12,5 +12,10 @@ module AccountScripts {
     public(script) fun disable_auto_accept_token(account: signer) {
         Account::set_auto_accept_token(&account, false);
     }
+
+    /// Remove zero Balance 
+    public(script) fun remove_zero_balance<TokenType: store>(account: signer) {
+        Account::remove_zero_balance<TokenType>(&account);
+    }
 }
 }

sources/NFT.move

@@ -879,6 +879,25 @@ module NFTGallery {
         let gallery = borrow_global_mut<NFTGallery<NFTMeta, NFTBody>>(owner);
         Vector::length(&gallery.items)
     }
+
+    /// Remove empty NFTGallery<Meta,Body>.
+    public fun remove_empty_gallery<NFTMeta: copy + store + drop, NFTBody: store>(sender: &signer) acquires NFTGallery{
+        let sender_addr = Signer::address_of(sender);
+        let NFTGallery<NFTMeta, NFTBody> {withdraw_events, deposit_events, items} = move_from<NFTGallery<NFTMeta, NFTBody>>(sender_addr);
+
+        Event::destroy_handle<WithdrawEvent<NFTMeta>>(withdraw_events);
+        Event::destroy_handle<DepositEvent<NFTMeta>>(deposit_events);           
+        Vector::destroy_empty<NFT<NFTMeta, NFTBody>>(items);
+    }
+
+    spec remove_empty_gallery {
+        let sender_addr = Signer::address_of(sender);
+        aborts_if !exists<NFTGallery<NFTMeta, NFTBody>>(sender_addr);
+
+        let gallery = global<NFTGallery<NFTMeta, NFTBody>>(sender_addr);
+        aborts_if Vector::length(&gallery) > 0;
+    }
+
 }
 
 module NFTGalleryScripts {
@@ -900,5 +919,10 @@ module NFTGalleryScripts {
     ) {
         NFTGallery::transfer<NFTMeta, NFTBody>(&sender, id, receiver);
     }
+
+    /// Remove empty NFTGallery<Meta,Body>.
+    public(script) fun remove_empty_gallery<NFTMeta: copy + store + drop, NFTBody: store>(sender: signer) {
+        NFTGallery::remove_empty_gallery<NFTMeta, NFTBody>(&sender);
+    }
 }
 }