Add burn to giftable tokebs

python/giftable_erc20_token/factory.py

@@ -12,6 +12,9 @@ from chainlib.eth.contract import (
         ABIContractEncoder,
         ABIContractType,
         )
+from chainlib.eth.constant import ZERO_ADDRESS
+from chainlib.jsonrpc import JSONRPCRequest
+from hexathon import add_0x
 
 # local imports
 from giftable_erc20_token.data import data_dir
@@ -107,6 +110,48 @@ class GiftableToken(ERC20):
         return tx
 
 
+    def burn(self, contract_address, sender_address, value, tx_format=TxFormat.JSONRPC):
+        enc = ABIContractEncoder()
+        enc.method('burn')
+        enc.typ(ABIContractType.UINT256)
+        enc.uint256(value)
+        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 burned(self, contract_address, sender_address=ZERO_ADDRESS, id_generator=None):
+        j = JSONRPCRequest(id_generator)
+        o = j.template()
+        o['method'] = 'eth_call'
+        enc = ABIContractEncoder()
+        enc.method('burned')
+        data = add_0x(enc.get())
+        tx = self.template(sender_address, contract_address)
+        tx = self.set_code(tx, data)
+        o['params'].append(self.normalize(tx))
+        o['params'].append('latest')
+        o = j.finalize(o)
+        return o
+
+
+    def total_minted(self, contract_address, sender_address=ZERO_ADDRESS, id_generator=None):
+        j = JSONRPCRequest(id_generator)
+        o = j.template()
+        o['method'] = 'eth_call'
+        enc = ABIContractEncoder()
+        enc.method('totalMinted')
+        data = add_0x(enc.get())
+        tx = self.template(sender_address, contract_address)
+        tx = self.set_code(tx, data)
+        o['params'].append(self.normalize(tx))
+        o['params'].append('latest')
+        o = j.finalize(o)
+        return o
+
+
 def bytecode(**kwargs):
     return GiftableToken.bytecode(version=kwargs.get('version'))
 

python/tests/test_giftable.py

@@ -80,5 +80,44 @@ class TestExpire(TestGiftableExpireToken):
         self.assertEqual(supply, mint_amount)
 
 
+    def test_burn(self):
+        mint_amount = self.initial_supply
+        nonce_oracle = RPCNonceOracle(self.accounts[1], self.rpc)
+        c = GiftableToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+        (tx_hash, o) = c.burn(self.address, self.accounts[1], int(mint_amount / 4))
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 0)
+
+        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+        c = GiftableToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+        (tx_hash, o) = c.burn(self.address, self.accounts[0], int(mint_amount / 4))
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.burned(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        burned = c.parse_balance(r)
+        self.assertEqual(burned, int(mint_amount / 4))
+
+        o = c.balance_of(self.address, self.accounts[0], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        balance = c.parse_balance(r)
+        self.assertEqual(balance, mint_amount - burned)
+
+        o = c.total_supply(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        balance = c.parse_balance(r)
+        self.assertEqual(balance, mint_amount - burned)
+
+        o = c.total_minted(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        balance = c.parse_balance(r)
+        self.assertEqual(balance, mint_amount)
+
+
 if __name__ == '__main__':
     unittest.main()