Add sweep function

python/CHANGELOG

@@ -1,3 +1,5 @@
+- 0.3.7
+	* Add sweep contract method to fully empty one account into another
 - 0.3.6
 	* Reinstate owner as minter by default
 - 0.3.0

python/erc20_demurrage_token/token.py

@@ -443,6 +443,19 @@ class DemurrageToken(ERC20, SealedContract, ExpiryContract):
         return tx
 
 
+    def sweep(self, contract_address, sender_address, recipient_address, tx_format=TxFormat.JSONRPC):
+        enc = ABIContractEncoder()
+        enc.method('sweep')
+        enc.typ(ABIContractType.ADDRESS)
+        enc.address(recipient_address)
+        data = enc.get()
+        tx = self.template(sender_address, contract_address, use_nonce=True)
+        tx = self.set_code(tx, data)
+        tx = self.finalize(tx, tx_format)
+        return tx
+
+
+
     def apply_demurrage(self, contract_address, sender_address, limit=0, tx_format=TxFormat.JSONRPC):
         if limit == 0:
             return self.transact_noarg('applyDemurrage', contract_address, sender_address)
@@ -474,8 +487,6 @@ class DemurrageToken(ERC20, SealedContract, ExpiryContract):
         return tx
 
 
-
-
     def tax_level(self, contract_address, sender_address=ZERO_ADDRESS):
         return self.call_noarg('taxLevel', contract_address, sender_address=sender_address)
 

python/setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = erc20-demurrage-token
-version = 0.3.6
+version = 0.3.7
 description = ERC20 token with redistributed continual demurrage
 author = Louis Holbrook
 author_email = dev@holbrook.no

python/tests/test_amounts.py

@@ -122,5 +122,26 @@ class TestAmounts(TestDemurrageDefault):
             self.assert_within_lower(balance, case[1], 10000)
 
 
+    def test_sweep(self):
+        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+        (tx_hash, o) = c.mint_to(self.address, self.accounts[0], self.accounts[0], 2000)
+        r = self.rpc.do(o)
+
+        (tx_hash, o) = c.sweep(self.address, self.accounts[0], self.accounts[1])
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.balance_of(self.address, self.accounts[0], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        self.assertEqual(c.parse_balance(r), 0)
+ 
+        o = c.balance_of(self.address, self.accounts[1], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        self.assert_within(c.parse_balance(r), 2000, 1)
+ 
+
 if __name__ == '__main__':
     unittest.main()

solidity/DemurrageTokenSingleNocap.sol

@@ -292,6 +292,16 @@ contract DemurrageTokenSingleNocap {
 		return true;
 	}
 
+	// Send full balance of one account to another
+	function sweep(address _account) public returns (uint256) {
+		uint256 v;
+
+		v = account[msg.sender];
+		account[msg.sender] = 0;
+		account[_account] += v;
+		return v;
+	}
+
 	// Creates new tokens out of thin air, and allocates them to the given address
 	// Triggers tax
 	function mintTo(address _beneficiary, uint256 _amount) external returns (bool) {