Move bitfields to struct

Runaway redistribution

See merge request cicnet/erc20-demurrage-token!10

CAVEAT

@@ -0,0 +1,5 @@
+The contract is intended for slow rates of decay (e.g. 2% per month). Very high levels of decay (2% per minute) will lead to overflows, and will need a more flexible implementation to support it.
+
+The contract is written with frequent usage in mind. If used for tokens with low usage freqency (e.g. several days idle), it is recommended to run a continuous process triggering the changePeriod() contract call, to reduce the amount of exponential calculation the application of demurrage will trigger.
+
+When changing the period, the supply for the consecutive period will be taken at the time of code execution, and thus not necessarily at the time when the redistribution period threshold was crossed. 

ROADMAP

@@ -0,0 +1,8 @@
+- 0.1.3
+	* Snapshot supply for crossed redistribution thresholds before minting new tokens.
+- 0.1.4
+	* Implement natural logarithm 
+- 0.1.5
+	* Port changes from SingleNocap to SingleCap
+- 0.2.0
+	* Make decay resolutions configurable, to support high levels of decay.

VERSION

@@ -0,0 +1 @@
+0.1.2

python/CHANGELOG

@@ -1,3 +1,13 @@
+- 0.2.0
+	* Add token burn function
+	* Fix gas leak when calculating decay on period change
+	* Remove all but SingleNocap contract in make install
+	* Make approve explicitly set value
+	* Add increaseAllowance and decreaseAllowance methods
+- 0.1.1
+	* Settable demurrage steps for apply demurrage cli tool
+- 0.1.0
+	* Dependency upgrades
 - 0.0.11
 	* Apply demurrage cli tool
 - 0.0.10

python/erc20_demurrage_token/demurrage.py

@@ -9,8 +9,7 @@ from chainlib.eth.constant import ZERO_ADDRESS
 # local imports
 from .token import DemurrageToken
 
-logging.basicConfig(level=logging.DEBUG)
-logg = logging.getLogger()
+logg = logging.getLogger(__name__)
 
 
 class DemurrageCalculator:

python/erc20_demurrage_token/runnable/apply.py

@@ -11,24 +11,34 @@ import os
 import json
 import argparse
 import logging
+import datetime
+import math
 
 # external imports
 import confini
-from funga.eth.signer import EIP155Signer
-from funga.eth.keystore.dict import DictKeystore
-from chainlib.chain import ChainSpec
-from chainlib.eth.nonce import (
-        RPCNonceOracle,
-        OverrideNonceOracle,
-        )
-from chainlib.eth.gas import (
-        RPCGasOracle,
-        OverrideGasOracle,
+import chainlib.eth.cli
+from chainlib.eth.block import (
+        block_latest,
+        block_by_number,
+        Block,
         )
 from chainlib.eth.connection import EthHTTPConnection
 from chainlib.eth.tx import receipt
 from chainlib.eth.constant import ZERO_ADDRESS
+from hexathon import to_int as hex_to_int
 import chainlib.eth.cli
+from chainlib.eth.settings import process_settings
+from chainlib.settings import ChainSettings
+from chainlib.eth.cli.arg import (
+        Arg,
+        ArgFlag,
+        process_args,
+        )
+from chainlib.eth.cli.config import (
+        Config,
+        process_config,
+        )
+from chainlib.eth.cli.log import process_log
 
 # local imports
 import erc20_demurrage_token
@@ -37,53 +47,105 @@ from erc20_demurrage_token import (
         DemurrageTokenSettings,
         )
 
-logging.basicConfig(level=logging.WARNING)
 logg = logging.getLogger()
 
-script_dir = os.path.dirname(__file__)
-data_dir = os.path.join(script_dir, '..', 'data')
 
-config_dir = os.path.join(data_dir, 'config')
+def process_config_local(config, arg, args, flags):
+    config.add(args.steps, '_STEPS', False)
+    return config
 
-arg_flags = chainlib.eth.cli.argflag_std_write | chainlib.eth.cli.Flag.EXEC
-argparser = chainlib.eth.cli.ArgumentParser(arg_flags)
+
+arg_flags = ArgFlag()
+arg = Arg(arg_flags)
+flags = arg_flags.STD_WRITE | arg_flags.EXEC | arg_flags.WALLET
+
+argparser = chainlib.eth.cli.ArgumentParser()
+argparser = process_args(argparser, arg, flags)
+argparser.add_argument('--steps', type=int, default=0, help='Max demurrage steps to apply per round')
 args = argparser.parse_args()
-config = chainlib.eth.cli.Config.from_args(args, arg_flags, default_fee_limit=DemurrageToken.gas(), base_config_dir=config_dir)
 
-wallet = chainlib.eth.cli.Wallet()
-wallet.from_config(config)
+logg = process_log(args, logg)
 
-rpc = chainlib.eth.cli.Rpc(wallet=wallet)
-conn = rpc.connect_by_config(config)
+config = Config()
+config = process_config(config, arg, args, flags)
+config = process_config_local(config, arg, args, flags)
+logg.debug('config loaded:\n{}'.format(config))
 
-chain_spec = ChainSpec.from_chain_str(config.get('CHAIN_SPEC'))
+settings = ChainSettings()
+settings = process_settings(settings, config)
+logg.debug('settings loaded:\n{}'.format(settings))
 
 
 def main():
-    signer = rpc.get_signer()
-    signer_address = rpc.get_sender_address()
+    chain_spec = settings.get('CHAIN_SPEC')
+    conn = settings.get('CONN')
+    o = block_latest()
+    r = conn.do(o)
+ 
+    block_start_number = None
+    try:
+        block_start_number = hex_to_int(r)
+    except TypeError:
+        block_start_number = int(r)
 
-    gas_oracle = rpc.get_gas_oracle()
-    nonce_oracle = rpc.get_nonce_oracle()
+    o = block_by_number(block_start_number)
+    r = conn.do(o)
 
-    c = DemurrageToken(chain_spec, signer=signer, gas_oracle=gas_oracle, nonce_oracle=nonce_oracle)
-    (tx_hash_hex, o) = c.apply_demurrage(config.get('_EXEC_ADDRESS'), signer_address)
-    if config.get('_RPC_SEND'):
-        conn.do(o)
-        if config.get('_WAIT'):
-            r = conn.wait(tx_hash_hex)
-            if r['status'] == 0:
-                sys.stderr.write('EVM revert while deploying contract. Wish I had more to tell you')
-                sys.exit(1)
-            # TODO: pass through translator for keys (evm tester uses underscore instead of camelcase)
-            address = r['contractAddress']
+    block_start = Block(r)
+    block_start_timestamp = block_start.timestamp
+    block_start_datetime = datetime.datetime.fromtimestamp(block_start_timestamp)
 
-            print(address)
-        else:
+    gas_oracle = settings.get('FEE_ORACLE')
+    c = DemurrageToken(chain_spec, gas_oracle=gas_oracle)
+    o = c.demurrage_timestamp(settings.get('EXEC'))
+    r = conn.do(o)
+
+    demurrage_timestamp = None
+    try:
+        demurrage_timestamp = hex_to_int(r)
+    except TypeError:
+        demurrage_timestamp = int(r)
+    demurrage_datetime = datetime.datetime.fromtimestamp(demurrage_timestamp)
+
+    total_seconds = block_start_timestamp - demurrage_timestamp
+    total_steps = total_seconds / 60
+
+    if total_steps < 1.0:
+        logg.error('only {} seconds since last demurrage application, skipping'.format(total_seconds))
+        return
+
+    logg.debug('block start is at {} demurrage is at {} -> {} minutes'.format(
+        block_start_datetime,
+        demurrage_datetime,
+        total_steps,
+        ))
+
+    rounds = 1
+    if config.get('_STEPS') > 0:
+        rounds = math.ceil(total_steps / config.get('_STEPS'))
+
+    logg.info('will perform {} rounds of {} steps'.format(rounds, config.get('_STEPS')))
+
+    last_tx_hash = None
+    for i in range(rounds):
+        signer = settings.get('SIGNER')
+        signer_address = settings.get('SENDER_ADDRESS')
+
+        nonce_oracle = settings.get('NONCE_ORACLE')
+
+        c = DemurrageToken(chain_spec, signer=signer, gas_oracle=gas_oracle, nonce_oracle=nonce_oracle)
+        (tx_hash_hex, o) = c.apply_demurrage(config.get('_EXEC_ADDRESS'), signer_address, limit=config.get('_STEPS'))
+        if settings.get('RPC_SEND'):
             print(tx_hash_hex)
+            conn.do(o)
+            if config.true('_WAIT_ALL') or (i == rounds - 1 and config.true('_WAIT')):
+                r = conn.wait(tx_hash_hex)
+                if r['status'] == 0:
+                    sys.stderr.write('EVM revert while deploying contract. Wish I had more to tell you')
+                    sys.exit(1)
+        else:
+            print(o)
 
-    else:
-        print(o)
 
 
 if __name__ == '__main__':

python/erc20_demurrage_token/runnable/deploy.py

@@ -14,21 +14,22 @@ import logging
 
 # external imports
 import confini
-from funga.eth.signer import EIP155Signer
-from funga.eth.keystore.dict import DictKeystore
-from chainlib.chain import ChainSpec
-from chainlib.eth.nonce import (
-        RPCNonceOracle,
-        OverrideNonceOracle,
-        )
-from chainlib.eth.gas import (
-        RPCGasOracle,
-        OverrideGasOracle,
-        )
 from chainlib.eth.connection import EthHTTPConnection
 from chainlib.eth.tx import receipt
 from chainlib.eth.constant import ZERO_ADDRESS
 import chainlib.eth.cli
+from chainlib.eth.settings import process_settings
+from chainlib.settings import ChainSettings
+from chainlib.eth.cli.arg import (
+        Arg,
+        ArgFlag,
+        process_args,
+        )
+from chainlib.eth.cli.config import (
+        Config,
+        process_config,
+        )
+from chainlib.eth.cli.log import process_log
 
 # local imports
 import erc20_demurrage_token
@@ -37,84 +38,75 @@ from erc20_demurrage_token import (
         DemurrageTokenSettings,
         )
 
-logging.basicConfig(level=logging.WARNING)
 logg = logging.getLogger()
 
-script_dir = os.path.dirname(__file__)
-data_dir = os.path.join(script_dir, '..', 'data')
 
-config_dir = os.path.join(data_dir, 'config')
+def process_config_local(config, arg, args, flags):
+    config.add(args.token_name, 'TOKEN_NAME', False)
+    config.add(args.token_symbol, 'TOKEN_SYMBOL', False)
+    config.add(args.token_decimals, 'TOKEN_DECIMALS', False)
+    config.add(args.sink_address, 'TOKEN_SINK_ADDRESS', False)
+    config.add(args.redistribution_period, 'TOKEN_REDISTRIBUTION_PERIOD', False)
+    config.add(args.demurrage_level, 'TOKEN_DEMURRAGE_LEVEL', False)
+    config.add(0, 'TOKEN_SUPPLY_LIMIT', False)
+    return config
 
-arg_flags = chainlib.eth.cli.argflag_std_write
-argparser = chainlib.eth.cli.ArgumentParser(arg_flags)
+
+arg_flags = ArgFlag()
+arg = Arg(arg_flags)
+flags = arg_flags.STD_WRITE | arg_flags.EXEC | arg_flags.WALLET
+
+argparser = chainlib.eth.cli.ArgumentParser()
+argparser = process_args(argparser, arg, flags)
 argparser.add_argument('--name', dest='token_name', type=str, help='Token name')
 argparser.add_argument('--symbol', dest='token_symbol', required=True, type=str, help='Token symbol')
 argparser.add_argument('--decimals', dest='token_decimals', type=int, help='Token decimals')
 argparser.add_argument('--sink-address', dest='sink_address', type=str, help='demurrage level,ppm per minute') 
-argparser.add_argument('--supply-limit', dest='supply_limit', type=int, help='token supply limit (0 = no limit)')
-argparser.add_argument('--redistribution-period', type=int, help='redistribution period, minutes (0 = deactivate)') # default 10080 = week
-argparser.add_argument('--multi', action='store_true', help='automatic redistribution')
+#argparser.add_argument('--supply-limit', dest='supply_limit', type=int, help='token supply limit (0 = no limit)')
+argparser.add_argument('--redistribution-period', dest='redistribution_period', type=int, help='redistribution period, minutes (0 = deactivate)') # default 10080 = week
+#argparser.add_argument('--multi', action='store_true', help='automatic redistribution')
 argparser.add_argument('--demurrage-level', dest='demurrage_level', type=int, help='demurrage level, ppm per minute') 
 args = argparser.parse_args()
 
-arg_flags = chainlib.eth.cli.argflag_std_write
+logg = process_log(args, logg)
 
-extra_args = {
-        'redistribution_period': 'TOKEN_REDISTRIBUTION_PERIOD',
-        'demurrage_level': 'TOKEN_DEMURRAGE_LEVEL',
-        'supply_limit': 'TOKEN_SUPPLY_LIMIT',
-        'token_name': 'TOKEN_NAME',
-        'token_symbol': 'TOKEN_SYMBOL',
-        'token_decimals': 'TOKEN_DECIMALS',
-        'sink_address': 'TOKEN_SINK_ADDRESS',
-        'multi': None,
-        }
-config = chainlib.eth.cli.Config.from_args(args, arg_flags, extra_args=extra_args, default_fee_limit=DemurrageToken.gas(), base_config_dir=config_dir)
-
-if not bool(config.get('TOKEN_NAME')):
-    logg.info('token name not set, using symbol {} as name'.format(config.get('TOKEN_SYMBOL')))
-    config.add(config.get('TOKEN_SYMBOL'), 'TOKEN_NAME', True)
-
-if config.get('TOKEN_SUPPLY_LIMIT') == None:
-    config.add(0, 'TOKEN_SUPPLY_LIMIT', True)
-
-if config.get('TOKEN_REDISTRIBUTION_PERIOD') == None:
-    config.add(10800, 'TOKEN_REDISTRIBUTION_PERIOD', True)
+config = Config()
+config = process_config(config, arg, args, flags)
+config = process_config_local(config, arg, args, flags)
 logg.debug('config loaded:\n{}'.format(config))
 
-wallet = chainlib.eth.cli.Wallet()
-wallet.from_config(config)
+settings = ChainSettings()
+settings = process_settings(settings, config)
+logg.debug('settings loaded:\n{}'.format(settings))
 
-rpc = chainlib.eth.cli.Rpc(wallet=wallet)
-conn = rpc.connect_by_config(config)
-
-chain_spec = ChainSpec.from_chain_str(config.get('CHAIN_SPEC'))
 
 def main():
-    signer = rpc.get_signer()
-    signer_address = rpc.get_sender_address()
+    chain_spec = settings.get('CHAIN_SPEC')
+    conn = settings.get('CONN')
+    signer = settings.get('SIGNER')
+    signer_address = settings.get('SENDER_ADDRESS')
 
-    gas_oracle = rpc.get_gas_oracle()
-    nonce_oracle = rpc.get_nonce_oracle()
+    gas_oracle = settings.get('FEE_ORACLE')
+    nonce_oracle = settings.get('NONCE_ORACLE')
 
     c = DemurrageToken(chain_spec, signer=signer, gas_oracle=gas_oracle, nonce_oracle=nonce_oracle)
-    settings = DemurrageTokenSettings()
-    settings.name = config.get('TOKEN_NAME')
-    settings.symbol = config.get('TOKEN_SYMBOL')
-    settings.decimals = int(config.get('TOKEN_DECIMALS'))
-    settings.demurrage_level = int(config.get('TOKEN_DEMURRAGE_LEVEL'))
-    settings.period_minutes = int(config.get('TOKEN_REDISTRIBUTION_PERIOD'))
-    settings.sink_address = config.get('TOKEN_SINK_ADDRESS')
+    token_settings = DemurrageTokenSettings()
+    token_settings.name = config.get('TOKEN_NAME')
+    token_settings.symbol = config.get('TOKEN_SYMBOL')
+    token_settings.decimals = int(config.get('TOKEN_DECIMALS'))
+    token_settings.demurrage_level = int(config.get('TOKEN_DEMURRAGE_LEVEL'))
+    token_settings.period_minutes = int(config.get('TOKEN_REDISTRIBUTION_PERIOD'))
+    token_settings.sink_address = config.get('TOKEN_SINK_ADDRESS')
 
     (tx_hash_hex, o) = c.constructor(
             signer_address,
-            settings,
+            token_settings,
             redistribute=config.true('_MULTI'),
             cap=int(config.get('TOKEN_SUPPLY_LIMIT')),
             )
-    if config.get('_RPC_SEND'):
+    if settings.get('RPC_SEND'):
         conn.do(o)
-        if config.get('_WAIT'):
+        if config.true('_WAIT'):
             r = conn.wait(tx_hash_hex)
             if r['status'] == 0:
                 sys.stderr.write('EVM revert while deploying contract. Wish I had more to tell you')

python/erc20_demurrage_token/token.py

@@ -38,6 +38,15 @@ class DemurrageTokenSettings:
         self.sink_address = None
 
 
+    def __str__(self):
+        return 'name {} demurrage level {} period minutes {} sink address {}'.format(
+                self.name,
+                self.demurrage_level,
+                self.period_minutes,
+                self.sink_address,
+                )
+
+
 class DemurrageToken(ERC20):
 
     __abi = {}
@@ -108,6 +117,34 @@ class DemurrageToken(ERC20):
         return DemurrageToken.__bytecode[name]
 
 
+    def increase_allowance(self, contract_address, sender_address, address, value, tx_format=TxFormat.JSONRPC):
+        enc = ABIContractEncoder()
+        enc.method('increaseAllowance')
+        enc.typ(ABIContractType.ADDRESS)
+        enc.typ(ABIContractType.UINT256)
+        enc.address(address)
+        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 decrease_allowance(self, contract_address, sender_address, address, value, tx_format=TxFormat.JSONRPC):
+        enc = ABIContractEncoder()
+        enc.method('decreaseAllowance')
+        enc.typ(ABIContractType.ADDRESS)
+        enc.typ(ABIContractType.UINT256)
+        enc.address(address)
+        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 add_minter(self, contract_address, sender_address, address, tx_format=TxFormat.JSONRPC):
         enc = ABIContractEncoder()
         enc.method('addMinter')
@@ -146,6 +183,33 @@ class DemurrageToken(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 total_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('totalBurned')
+        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 to_base_amount(self, contract_address, value, sender_address=ZERO_ADDRESS, id_generator=None):
         j = JSONRPCRequest(id_generator)
         o = j.template()
@@ -246,8 +310,11 @@ class DemurrageToken(ERC20):
         o['method'] = 'eth_call'
         enc = ABIContractEncoder()
         enc.method('toRedistributionPeriod')
-        enc.typ(ABIContractType.BYTES32)
-        enc.bytes32(redistribution)
+        v = strip_0x(redistribution)
+        enc.typ_literal('(uint32,uint72,uint104)')
+        enc.bytes32(v[:64])
+        enc.bytes32(v[64:128])
+        enc.bytes32(v[128:192])
         data = add_0x(enc.get())
         tx = self.template(sender_address, contract_address)
         tx = self.set_code(tx, data)
@@ -257,22 +324,26 @@ class DemurrageToken(ERC20):
         return o
 
 
-    def to_redistribution_participants(self, contract_address, redistribution, sender_address=ZERO_ADDRESS, id_generator=None):
-        j = JSONRPCRequest(id_generator)
-        o = j.template()
-        o['method'] = 'eth_call'
-        enc = ABIContractEncoder()
-        enc.method('toRedistributionParticipants')
-        enc.typ(ABIContractType.BYTES32)
-        enc.bytes32(redistribution)
-        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 to_redistribution_participants(self, contract_address, redistribution, sender_address=ZERO_ADDRESS, id_generator=None):
+#        j = JSONRPCRequest(id_generator)
+#        o = j.template()
+#        o['method'] = 'eth_call'
+#        enc = ABIContractEncoder()
+#        enc.method('toRedistributionParticipants')
+#        v = strip_0x(redistribution)
+#        enc.typ_literal('(uint32,uint72,uint104)')
+#        #enc.typ(ABIContractType.BYTES32)
+#        enc.bytes32(v[:64])
+#        enc.bytes32(v[64:128])
+#        enc.bytes32(v[128:192])
+#        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 to_redistribution_supply(self, contract_address, redistribution, sender_address=ZERO_ADDRESS, id_generator=None):
         j = JSONRPCRequest(id_generator)
@@ -280,8 +351,11 @@ class DemurrageToken(ERC20):
         o['method'] = 'eth_call'
         enc = ABIContractEncoder()
         enc.method('toRedistributionSupply')
-        enc.typ(ABIContractType.BYTES32)
-        enc.bytes32(redistribution)
+        v = strip_0x(redistribution)
+        enc.typ_literal('(uint32,uint72,uint104)')
+        enc.bytes32(v[:64])
+        enc.bytes32(v[64:128])
+        enc.bytes32(v[128:192])
         data = add_0x(enc.get())
         tx = self.template(sender_address, contract_address)
         tx = self.set_code(tx, data)
@@ -297,8 +371,11 @@ class DemurrageToken(ERC20):
         o['method'] = 'eth_call'
         enc = ABIContractEncoder()
         enc.method('toRedistributionDemurrageModifier')
-        enc.typ(ABIContractType.BYTES32)
-        enc.bytes32(redistribution)
+        v = strip_0x(redistribution)
+        enc.typ_literal('(uint32,uint72,uint104)')
+        enc.bytes32(v[:64])
+        enc.bytes32(v[64:128])
+        enc.bytes32(v[128:192])
         data = add_0x(enc.get())
         tx = self.template(sender_address, contract_address)
         tx = self.set_code(tx, data)
@@ -380,28 +457,32 @@ class DemurrageToken(ERC20):
         return self.call_noarg('demurrageAmount', contract_address, sender_address=sender_address)
 
 
+    def demurrage_timestamp(self, contract_address, sender_address=ZERO_ADDRESS):
+        return self.call_noarg('demurrageTimestamp', contract_address, sender_address=sender_address)
+
+
     def supply_cap(self, contract_address, sender_address=ZERO_ADDRESS):
         return self.call_noarg('supplyCap', contract_address, sender_address=sender_address)
 
 
-    def grow_by(self, contract_address, value, period, sender_address=ZERO_ADDRESS, id_generator=None):
-        j = JSONRPCRequest(id_generator)
-        o = j.template()
-        o['method'] = 'eth_call'
-        enc = ABIContractEncoder()
-        enc.method('growBy')
-        enc.typ(ABIContractType.UINT256)
-        enc.typ(ABIContractType.UINT256)
-        enc.uint256(value)
-        enc.uint256(period)
-        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 grow_by(self, contract_address, value, period, sender_address=ZERO_ADDRESS, id_generator=None):
+#        j = JSONRPCRequest(id_generator)
+#        o = j.template()
+#        o['method'] = 'eth_call'
+#        enc = ABIContractEncoder()
+#        enc.method('growBy')
+#        enc.typ(ABIContractType.UINT256)
+#        enc.typ(ABIContractType.UINT256)
+#        enc.uint256(value)
+#        enc.uint256(period)
+#        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 decay_by(self, contract_address, value, period, sender_address=ZERO_ADDRESS, id_generator=None):
         j = JSONRPCRequest(id_generator)
@@ -447,8 +528,11 @@ class DemurrageToken(ERC20):
         o['method'] = 'eth_call'
         enc = ABIContractEncoder()
         enc.method('getDistributionFromRedistribution')
-        enc.typ(ABIContractType.BYTES32)
-        enc.bytes32(redistribution)
+        v = strip_0x(redistribution)
+        enc.typ_literal('(uint32,uint72,uint104)')
+        enc.bytes32(v[:64])
+        enc.bytes32(v[64:128])
+        enc.bytes32(v[128:192])
         data = add_0x(enc.get())
         tx = self.template(sender_address, contract_address)
         tx = self.set_code(tx, data)
@@ -513,6 +597,7 @@ class DemurrageToken(ERC20):
     def parse_supply_cap(self, v):
         return abi_decode_single(ABIContractType.UINT256, v)
 
+
     @classmethod
     def parse_grow_by(self, v):
         return abi_decode_single(ABIContractType.UINT256, v)
@@ -536,3 +621,8 @@ class DemurrageToken(ERC20):
     @classmethod
     def parse_resolution_factor(self, v):
         return abi_decode_single(ABIContractType.UINT256, v)
+
+
+    @classmethod
+    def parse_total_burned(self, v):
+        return abi_decode_single(ABIContractType.UINT256, v)

python/erc20_demurrage_token/unittest/base.py

@@ -20,7 +20,7 @@ from erc20_demurrage_token import (
         DemurrageToken,
         )
 
-logg = logging.getLogger()
+logg = logging.getLogger(__name__)
 
 #BLOCKTIME = 5 # seconds
 TAX_LEVEL = int(10000 * 2) # 2%
@@ -32,18 +32,19 @@ PERIOD = 10
 
 class TestTokenDeploy:
 
-    def __init__(self, rpc, token_symbol='FOO', token_name='Foo Token', sink_address=ZERO_ADDRESS, supply=10**12):
-        self.tax_level = TAX_LEVEL
-        self.period_seconds = PERIOD * 60
+    def __init__(self, rpc, token_symbol='FOO', token_name='Foo Token', sink_address=ZERO_ADDRESS, supply=10**12, tax_level=TAX_LEVEL, period=PERIOD):
+        self.tax_level = tax_level
+        self.period_seconds = period * 60
 
         self.settings = DemurrageTokenSettings()
         self.settings.name = token_name
         self.settings.symbol = token_symbol
         self.settings.decimals = 6
-        self.settings.demurrage_level = TAX_LEVEL * (10 ** 32)
-        self.settings.period_minutes = PERIOD
+        self.settings.demurrage_level = tax_level * (10 ** 32)
+        self.settings.period_minutes = period
         self.settings.sink_address = sink_address
         self.sink_address = self.settings.sink_address
+        logg.debug('using demurrage token settings: {}'.format(self.settings))
 
         o = block_latest()
         self.start_block = rpc.do(o)
@@ -94,14 +95,12 @@ class TestDemurrage(EthTesterCase):
 
     def setUp(self):
         super(TestDemurrage, self).setUp()
-#        token_deploy = TestTokenDeploy()
-#        self.settings = token_deploy.settings
-#        self.sink_address = token_deploy.sink_address
-#        self.start_block = token_deploy.start_block
-#        self.start_time = token_deploy.start_time
-#        self.default_supply = self.default_supply
-#        self.default_supply_cap = self.default_supply_cap
-        self.deployer = TestTokenDeploy(self.rpc)
+        period = PERIOD
+        try:
+            period = getattr(self, 'period')
+        except AttributeError as e:
+            pass
+        self.deployer = TestTokenDeploy(self.rpc, period=period)
         self.default_supply = self.deployer.default_supply
         self.default_supply_cap = self.deployer.default_supply_cap
         self.start_block = None
@@ -127,6 +126,13 @@ class TestDemurrage(EthTesterCase):
         logg.debug('asserted within lower {} <= {} <= {}'.format(lower_target, v, target))
 
 
+    def assert_within_greater(self, v, target, tolerance_ppm):
+        higher_target = target + (target * (tolerance_ppm / 1000000))
+        self.assertLessEqual(v, higher_target)
+        self.assertGreaterEqual(v, target)
+        logg.debug('asserted within lower {} <= {} <= {}'.format(target, v, higher_target))
+
+
     def tearDown(self):
         pass
 
@@ -203,10 +209,11 @@ class TestDemurrageCap(TestDemurrage):
 class TestDemurrageUnit(TestDemurrage):
 
     def setUp(self):
-        super(TestDemurrage, self).setUp()
+        self.period = 1
+        self.period_seconds = self.period * 60
+        self.tax_level = TAX_LEVEL
 
-        self.tax_level = 50
-        self.period_seconds = 60
+        super(TestDemurrageUnit, self).setUp()
 
         nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
         self.settings = DemurrageTokenSettings()

python/requirements.txt

@@ -1,3 +1,3 @@
-chainlib-eth~=0.0.27
-eth-erc20~=0.1.10
-funga-eth~=0.5.6
+chainlib-eth~=0.4.11
+eth-erc20~=0.5.1
+funga-eth~=0.6.0

python/run_tests.sh

@@ -6,21 +6,30 @@ set -e
 export PYTHONPATH=.
 
 #modes=(MultiNocap MultiCap SingleCap SingleNocap)
-modes=(SingleCap SingleNocap) # other contracts need to be updted
+#modes=(SingleCap SingleNocap) # other contracts need to be updted
+modes=(SingleNocap) # other contracts need to be updted
 for m in ${modes[@]}; do
 	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_basic.py
 	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_growth.py
 	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_amounts.py
 	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_single.py
+	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_burn.py
 done
 
-modes=(SingleCap) # other contracts need to be updted
+#modes=(SingleCap) # other contracts need to be updted
+modes=()
 for m in ${modes[@]}; do
 	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_period.py
-#	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_redistribution_unit.py
 done
 
-modes=(MultiCap SingleCap)
+modes=(SingleNocap) # other contracts need to be updted
+for m in ${modes[@]}; do
+	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_redistribution_unit.py
+	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_redistribution_single.py
+done
+
+#modes=(MultiCap SingleCap)
+modes=()
 for m in ${modes[@]}; do
 	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_cap.py
 done

python/setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = erc20-demurrage-token
-version = 0.0.11
+version = 0.2.0
 description = ERC20 token with redistributed continual demurrage
 author = Louis Holbrook
 author_email = dev@holbrook.no
@@ -25,12 +25,13 @@ licence_files =
 
 [options]
 include_package_data = True
-python_requires = >= 3.6
+python_requires = >= 3.7
 packages =
 	erc20_demurrage_token
 	erc20_demurrage_token.runnable
 	erc20_demurrage_token.data
 	erc20_demurrage_token.sim
+	erc20_demurrage_token.unittest
 
 [options.package_data]
 * =

python/tests/test_basic.py

@@ -276,7 +276,52 @@ class TestBasic(TestDemurrageDefault):
         r = self.rpc.do(o)
         self.assertEqual(r['status'], 1)
 
-       
+      
+    def test_approve(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.approve(self.address, self.accounts[0], self.accounts[1], 500)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+ 
+        (tx_hash, o) = c.approve(self.address, self.accounts[0], self.accounts[1], 600)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 0)
+
+        (tx_hash, o) = c.approve(self.address, self.accounts[0], self.accounts[1], 0)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        (tx_hash, o) = c.approve(self.address, self.accounts[0], self.accounts[1], 600)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        (tx_hash, o) = c.increase_allowance(self.address, self.accounts[0], self.accounts[1], 200)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        (tx_hash, o) = c.decrease_allowance(self.address, self.accounts[0], self.accounts[1], 800)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        (tx_hash, o) = c.approve(self.address, self.accounts[0], self.accounts[1], 42)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
 
     def test_transfer_from(self):
         nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
@@ -315,6 +360,12 @@ class TestBasic(TestDemurrageDefault):
         balance = c.parse_balance_of(r)
         self.assertEqual(balance, 500)
 
+        (tx_hash, o) = c.transfer_from(self.address, self.accounts[2], self.accounts[1], self.accounts[3], 1)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 0)
+
 
 if __name__ == '__main__':
     unittest.main()

python/tests/test_burn.py

@@ -0,0 +1,320 @@
+# standard imports
+import os
+import unittest
+import json
+import logging
+import datetime
+
+# external imports
+from chainlib.eth.constant import ZERO_ADDRESS
+from chainlib.eth.nonce import RPCNonceOracle
+from chainlib.eth.tx import receipt
+from chainlib.eth.block import (
+        block_latest,
+        block_by_number,
+    )
+
+# local imports
+from erc20_demurrage_token import DemurrageToken
+
+# test imports
+from erc20_demurrage_token.unittest.base import TestDemurrage
+
+logging.basicConfig(level=logging.INFO)
+logg = logging.getLogger()
+
+testdir = os.path.dirname(__file__)
+
+TAX_LEVEL = 2
+
+class TestBurn(TestDemurrage):
+
+    def setUp(self):
+        super(TestBurn, self).setUp()
+
+
+    def deploy(self, tax_level=None):
+        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+
+        self.mode = os.environ.get('ERC20_DEMURRAGE_TOKEN_TEST_MODE')
+        if self.mode == None:
+            self.mode = 'MultiNocap'
+        logg.debug('executing test setup default mode {}'.format(self.mode))
+
+        if tax_level != None:
+            self.deployer.settings.demurrage_level = tax_level * (10 ** 32)
+        self.deployer.settings.sink_address = self.accounts[9]
+        self.deployer.sink_address = self.accounts[9]
+        super(TestBurn, self).deploy(c, self.mode)
+
+        logg.info('deployed with mode {}'.format(self.mode))
+
+
+    # Burn tokens and immediately check balances and supply
+    def test_burn_basic(self):
+        self.deploy()
+        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[1], 1000000)
+        r = self.rpc.do(o)
+
+        nonce_oracle = RPCNonceOracle(self.accounts[1], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+        (tx_hash, o) = c.burn(self.address, self.accounts[1], 600000)
+        r = 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 = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+        (tx_hash, o) = c.add_minter(self.address, self.accounts[0], self.accounts[1])
+        r = self.rpc.do(o)
+
+        nonce_oracle = RPCNonceOracle(self.accounts[1], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+        (tx_hash, o) = c.burn(self.address, self.accounts[1], 600000)
+        r = self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.total_supply(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        new_supply = c.parse_total_supply(r)
+        self.assertEqual(new_supply, 400000)
+
+        o = c.total_burned(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        burned = c.parse_total_burned(r)
+        self.assertEqual(burned, 600000)
+
+
+    # burn tokens and check sink balance and supply after first redistribution period
+    def test_burned_redistribution(self):
+        self.deploy()
+        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], 1000000000)
+        r = self.rpc.do(o)
+
+        (tx_hash, o) = c.burn(self.address, self.accounts[0], 500000000)
+        r = self.rpc.do(o)
+
+        (tx_hash, o) = c.transfer(self.address, self.accounts[0], self.sink_address, 500000000)
+        r = self.rpc.do(o)
+
+        self.backend.time_travel(self.start_time + self.period_seconds)
+
+        o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bal = c.parse_balance(r)
+        self.assertEqual(bal, 416873881) # 9 periods demurrage
+
+        (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+        r = self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.total_supply(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        new_supply = c.parse_total_supply(r)
+        self.assertEqual(new_supply, 500000000)
+
+        o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bal = c.parse_balance(r)
+        self.assert_within_lower(bal, 500000000, 0.0025)
+
+        self.backend.time_travel(self.start_time + (self.period_seconds * 2))
+
+        (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+        r = self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.total_supply(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        new_supply = c.parse_total_supply(r)
+        self.assertEqual(new_supply, 500000000)
+
+        # if we don't burn anything more it should be the same 
+        o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bal = c.parse_balance(r)
+        self.assert_within_lower(bal, 500000000, 0.0025)
+
+
+    # burn tokens and check sink and taxed balance and supply after first redistribution period
+    def test_burned_other_redistribution(self):
+        self.deploy()
+        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], 1000000000)
+        r = self.rpc.do(o)
+
+        (tx_hash, o) = c.burn(self.address, self.accounts[0], 500000000)
+        r = self.rpc.do(o)
+
+        (tx_hash, o) = c.transfer(self.address, self.accounts[0], self.accounts[1], 500000000)
+        r = self.rpc.do(o)
+
+        self.backend.time_travel(self.start_time + self.period_seconds)
+
+        o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bal = c.parse_balance(r)
+        self.assertEqual(bal, 416873881) # 9 periods demurrage
+
+        (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+        r = self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.total_supply(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        new_supply = c.parse_total_supply(r)
+        self.assertEqual(new_supply, 500000000)
+
+        o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bal = c.parse_balance(r)
+        self.assertEqual(bal, 408536403) # 9 periods demurrage
+
+        o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        sink_bal = c.parse_balance(r)
+        self.assert_within_lower(sink_bal, 500000000 - 408536403, 0.09) # TODO is this ok variance, 1.0 is ppm?
+
+        self.backend.time_travel(self.start_time + (self.period_seconds * 2))
+
+        (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+        r = self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.total_supply(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        new_supply = c.parse_total_supply(r)
+        self.assertEqual(new_supply, 500000000)
+
+        o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        next_bal = c.parse_balance(r)
+        self.assertEqual(next_bal, 333803985) # 9 periods demurrage
+
+        o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        prev_sink_bal = sink_bal
+        bal = prev_sink_bal + (bal - next_bal)
+        sink_bal = c.parse_balance(r)
+        self.assert_within_lower(sink_bal, bal, 0.09) # TODO is this ok variance, 1.0 is ppm?
+
+
+    # verify expected results of balance and supply after multiple redistribution periods
+    def test_burn_accumulate(self):
+        self.deploy(tax_level=2/1000)
+        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+
+        (tx_hash, o) = c.add_minter(self.address, self.accounts[0], self.sink_address)
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        (tx_hash, o) = c.mint_to(self.address, self.accounts[0], self.sink_address, self.default_supply)
+        r = self.rpc.do(o)
+
+        balance_share = int(self.default_supply / 2)
+        nonce_oracle = RPCNonceOracle(self.sink_address, self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+        (tx_hash, o) = c.transfer(self.address, self.sink_address, self.accounts[1], balance_share)
+        r = self.rpc.do(o)
+
+        new_supply = None
+        burn_rate = 1000
+        sink_bal = None
+        bob_bal = None
+        bob_refund = None
+
+        o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bob_bal = c.parse_balance(r)
+        prev_bob_bal = bob_bal
+
+        iterations = 100
+
+        for i in range(1, iterations + 1):
+            nonce_oracle = RPCNonceOracle(self.sink_address, self.rpc)
+            c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+
+            if bob_refund != None:
+                (tx_hash, o) = c.transfer(self.address, self.sink_address, self.accounts[1], bob_refund)
+                r = self.rpc.do(o)
+                o = receipt(tx_hash)
+                r = self.rpc.do(o)
+                self.assertEqual(r['status'], 1)
+
+            (tx_hash, o) = c.burn(self.address, self.sink_address, burn_rate)
+            r = self.rpc.do(o)
+            o = receipt(tx_hash)
+            r = self.rpc.do(o)
+            self.assertEqual(r['status'], 1)
+
+            nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+            c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+            o = c.total_supply(self.address, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            new_supply = c.parse_total_supply(r)
+
+            self.backend.time_travel(self.start_time + (self.period_seconds * i))
+
+            (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+            self.rpc.do(o)
+            
+            o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            bob_bal = c.parse_balance(r)
+            bob_refund = prev_bob_bal - bob_bal
+
+            o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            burner_bal = c.parse_balance(r)
+
+            sum_supply = bob_bal + burner_bal
+          
+            o = c.total_burned(self.address, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            total_burned = c.parse_balance(r)
+
+            o = c.to_base_amount(self.address, total_burned, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            total_burned_base = c.parse_balance(r)
+
+            expected_supply = self.default_supply - (burn_rate * i)
+            logg.info('checking burn round {} balance burner {} bob {} supply {} expected {} summed {} burned {} base {}'.format(i, burner_bal, bob_bal, new_supply, expected_supply, sum_supply, total_burned, total_burned_base))
+            self.assertEqual(new_supply, expected_supply)
+
+        sum_supply = burner_bal + bob_bal
+        logg.debug('balances sink {} bob {} total {} supply real {} original {}'.format(sink_bal, bob_bal, sum_supply, new_supply, self.default_supply))
+
+        self.assert_within_lower(sum_supply, new_supply, 0.00001)
+        self.assert_within_greater(burner_bal, balance_share - total_burned, 0.1)
+
+        bob_delta = self.default_supply * ((2 / 1000000) / 1000)
+        self.assert_within_lower(bob_bal, balance_share - bob_delta, 0.1)
+        
+        self.assertEqual(total_burned, iterations * burn_rate)
+
+
+if __name__ == '__main__':
+    unittest.main()

python/tests/test_demurrage.py

@@ -0,0 +1,133 @@
+# standard imports
+import datetime
+import unittest
+import logging
+import os
+
+# external imports
+from chainlib.eth.nonce import RPCNonceOracle
+from chainlib.eth.tx import receipt
+
+# local imports
+from erc20_demurrage_token import DemurrageToken
+from erc20_demurrage_token.demurrage import DemurrageCalculator
+
+# test imports
+from erc20_demurrage_token.unittest.base import TestDemurrage
+
+logging.basicConfig(level=logging.INFO)
+logg = logging.getLogger()
+
+
+class TestDemurragePeriods(TestDemurrage):
+
+    def setUp(self):
+        super(TestDemurragePeriods, self).setUp()
+   
+        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+
+        self.mode = os.environ.get('ERC20_DEMURRAGE_TOKEN_TEST_MODE')
+        if self.mode == None:
+            self.mode = 'MultiNocap'
+        logg.debug('executing test setup default mode {}'.format(self.mode))
+
+        self.deployer.settings.demurrage_level = (2 / 1000) * (10 ** 32)
+        self.deployer.settings.sink_address = self.accounts[9]
+        self.deployer.sink_address = self.accounts[9]
+        self.deploy(c, self.mode)
+
+        logg.info('deployed with mode {}'.format(self.mode))
+
+
+    # verify that tax level calculation is in ppm as expected
+    def test_ppm(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[1], self.default_supply)
+        r = self.rpc.do(o)
+
+        self.backend.time_travel(self.start_time + 60)
+
+        (tx_hash, o) = c.apply_demurrage(self.address, self.accounts[0])
+        self.rpc.do(o)
+        o = receipt(tx_hash)
+        r = self.rpc.do(o)
+        self.assertEqual(r['status'], 1)
+
+        o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bob_bal = c.parse_balance(r)
+
+        o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        sink_bal = c.parse_balance(r)
+
+        o = c.total_supply(self.address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        new_supply = c.parse_total_supply(r)
+
+        balance_delta = self.default_supply * ((2 / 1000000) / 1000) 
+        self.assertEqual(bob_bal, self.default_supply - balance_delta)
+
+
+
+    # verify balances and supply after multiple demurrage periods
+    def test_over_time(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[1], self.default_supply)
+        r = self.rpc.do(o)
+
+        o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        bob_bal = c.parse_balance(r)
+        prev_bob_bal = bob_bal
+
+        nonce_oracle = RPCNonceOracle(self.sink_address, self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+
+        iterations = 100
+
+        for i in range(1, iterations + 1):
+            self.backend.time_travel(self.start_time + (self.period_seconds * i))
+
+            (tx_hash, o) = c.transfer(self.address, self.sink_address, self.accounts[1], prev_bob_bal - bob_bal)
+            r = self.rpc.do(o)
+            o = receipt(tx_hash)
+            r = self.rpc.do(o)
+            self.assertEqual(r['status'], 1)
+
+            (tx_hash, o) = c.apply_demurrage(self.address, self.sink_address)
+            self.rpc.do(o)
+            o = receipt(tx_hash)
+            r = self.rpc.do(o)
+            self.assertEqual(r['status'], 1)
+
+            o = c.balance(self.address, self.accounts[1], sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            bob_bal = c.parse_balance(r)
+
+            o = c.balance(self.address, self.sink_address, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            sink_bal = c.parse_balance(r)
+
+            o = c.total_supply(self.address, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            new_supply = c.parse_total_supply(r)
+
+            logg.info('round {} supply {} balance sink {} bob {}'.format(i, new_supply, sink_bal, bob_bal))
+
+        sum_supply = sink_bal + bob_bal
+
+        bob_delta = self.default_supply * ((2 / 1000000) / 100)
+
+        self.assert_within_lower(sum_supply, new_supply, 0.00001)
+        self.assert_within_greater(bob_bal, self.default_supply - bob_delta, 0.001)
+        self.assert_within_lower(sink_bal, bob_delta, 1000)
+        
+
+if __name__ == '__main__':
+    unittest.main()

python/tests/test_growth.py

@@ -28,23 +28,23 @@ testdir = os.path.dirname(__file__)
 
 class TestGrowth(TestDemurrageDefault):
 
-    def test_grow_by(self):
-        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
-        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
-
-        growth_factor = (1000000 + self.tax_level) / 1000000
-        v = 1000000000
-        o = c.grow_by(self.address, v, 1, sender_address=self.accounts[0])
-        r = self.rpc.do(o)
-        g = c.parse_grow_by(r)
-        self.assertEqual(int(v * growth_factor),  g)
-
-        period = 10
-        growth_factor = (1 + (self.tax_level) / 1000000) ** period
-        o = c.grow_by(self.address, v, period, sender_address=self.accounts[0])
-        r = self.rpc.do(o)
-        g = c.parse_grow_by(r)
-        self.assertEqual(int(v * growth_factor),  g)
+#    def test_grow_by(self):
+#        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+#        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+#
+#        growth_factor = (1000000 + self.tax_level) / 1000000
+#        v = 1000000000
+#        o = c.grow_by(self.address, v, 1, sender_address=self.accounts[0])
+#        r = self.rpc.do(o)
+#        g = c.parse_grow_by(r)
+#        self.assertEqual(int(v * growth_factor),  g)
+#
+#        period = 10
+#        growth_factor = (1 + (self.tax_level) / 1000000) ** period
+#        o = c.grow_by(self.address, v, period, sender_address=self.accounts[0])
+#        r = self.rpc.do(o)
+#        g = c.parse_grow_by(r)
+#        self.assertEqual(int(v * growth_factor),  g)
 
 
     def test_decay_by(self):
@@ -63,7 +63,7 @@ class TestGrowth(TestDemurrageDefault):
         o = c.decay_by(self.address, v, period, sender_address=self.accounts[0])
         r = self.rpc.do(o)
         g = c.parse_decay_by(r)
-        self.assertEqual(int(v * growth_factor),  g)
+        self.assertEqual(int(v * growth_factor), g)
 
 
 if __name__ == '__main__':

python/tests/test_redistribution.py

@@ -31,6 +31,8 @@ testdir = os.path.dirname(__file__)
 
 class TestRedistribution(TestDemurrageDefault):
 
+
+
     def test_whole_is_parts(self):
         nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
         c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)

python/tests/test_redistribution_single.py

@@ -0,0 +1,198 @@
+# standard imports
+import os
+import unittest
+import json
+import logging
+
+# external imports
+from chainlib.eth.constant import ZERO_ADDRESS
+from chainlib.eth.nonce import RPCNonceOracle
+from chainlib.eth.tx import receipt
+from chainlib.eth.block import (
+        block_latest,
+        block_by_number,
+        )
+from chainlib.eth.address import to_checksum_address
+from hexathon import (
+        strip_0x,
+        add_0x,
+        )
+
+# local imports
+from erc20_demurrage_token import DemurrageToken
+
+# test imports
+from erc20_demurrage_token.unittest.base import TestDemurrageDefault
+
+logging.basicConfig(level=logging.INFO)
+logg = logging.getLogger()
+
+testdir = os.path.dirname(__file__)
+
+class TestRedistribution(TestDemurrageDefault):
+
+
+    def test_redistribution_periods(self):
+        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+
+        demurrage = (1 - (self.tax_level / 1000000)) * (10**28)
+        supply = self.default_supply
+
+        (tx_hash, o) = c.mint_to(self.address, self.accounts[0], self.accounts[0], supply)
+        self.rpc.do(o)
+
+        for i in range(1, 10):
+            logg.debug('execute time travel to period {}'.format(i))
+            self.backend.time_travel(self.start_time + (self.period_seconds * i))
+            (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+            self.rpc.do(o)
+            o = receipt(tx_hash)
+            r = self.rpc.do(o)
+            self.assertEqual(r['status'], 1)
+
+            o = c.redistributions(self.address, i, sender_address=self.accounts[0])
+            redistribution = self.rpc.do(o)
+
+            o = c.to_redistribution_demurrage_modifier(self.address, redistribution, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            demurrage = c.parse_to_redistribution_item(r)
+
+            o = c.redistributions(self.address, i-1, sender_address=self.accounts[0])
+            redistribution = self.rpc.do(o)
+
+            o = c.to_redistribution_demurrage_modifier(self.address, redistribution, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            demurrage_previous = c.parse_to_redistribution_item(r)
+
+            o = c.balance_of(self.address, self.sink_address, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            balance_sink = c.parse_balance(r)
+
+            o = c.balance_of(self.address, self.accounts[0], sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            balance_minter = c.parse_balance(r)
+
+            logg.debug('testing sink {} mint {} adds up to supply {} with demurrage between {} and {}'.format(balance_sink, balance_minter, supply, demurrage_previous, demurrage))
+
+            self.assert_within_lower(balance_minter + balance_sink, supply, 0.001)
+
+
+    def test_redistribution_catchup_periods(self):
+        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+
+        demurrage = (1 - (self.tax_level / 1000000)) * (10**28)
+        supply = self.default_supply
+
+        (tx_hash, o) = c.mint_to(self.address, self.accounts[0], self.accounts[0], supply)
+        self.rpc.do(o)
+
+        self.backend.time_travel(self.start_time + (self.period_seconds * 100))
+
+        balance_minter = None
+        balance_sink = None
+        real_supply = None
+
+        for i in range(1, 101):
+            (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+            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.sink_address, sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            balance_sink = c.parse_balance(r)
+
+            o = c.balance_of(self.address, self.accounts[0], sender_address=self.accounts[0])
+            r = self.rpc.do(o)
+            balance_minter = c.parse_balance(r)
+            
+            real_supply = balance_sink + balance_minter
+            logg.info('period {} testing sink {} mint {} adds up to supply {} of original {} (delta {})'.format(i, balance_sink, balance_minter, real_supply, supply, supply - real_supply))
+
+        i = 100
+        o = c.redistributions(self.address, i, sender_address=self.accounts[0])
+        redistribution = self.rpc.do(o)
+
+        o = c.to_redistribution_demurrage_modifier(self.address, redistribution, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        demurrage = c.parse_to_redistribution_item(r)
+
+        o = c.redistributions(self.address, i-1, sender_address=self.accounts[0])
+        redistribution = self.rpc.do(o)
+
+        o = c.to_redistribution_demurrage_modifier(self.address, redistribution, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        demurrage_previous = c.parse_to_redistribution_item(r)
+
+        o = c.balance_of(self.address, self.sink_address, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        balance_sink = c.parse_balance(r)
+
+        o = c.balance_of(self.address, self.accounts[0], sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        balance_minter = c.parse_balance(r)
+
+        logg.debug('testing sink {} mint {} adds up to supply {} with demurrage between {} and {}'.format(balance_sink, balance_minter, real_supply, demurrage_previous, demurrage))
+
+        self.assert_within_lower(balance_minter + balance_sink, supply, 0.001)
+
+
+#    def test_redistribution_boundaries(self):
+#        nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
+#        c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
+#
+#        demurrage = (1 - (self.tax_level / 1000000)) * (10**28)
+#        supply = self.default_supply
+#
+#        (tx_hash, o) = c.mint_to(self.address, self.accounts[0], self.accounts[0], supply)
+#        self.rpc.do(o)
+#
+#        o = c.balance_of(self.address, self.sink_address, sender_address=self.accounts[0])
+#        r = self.rpc.do(o)
+#        balance = c.parse_balance(r)
+#        logg.debug('balance before {} supply {}'.format(balance, supply))
+#
+#        self.backend.time_travel(self.start_time + self.period_seconds)
+#        (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+#        r = self.rpc.do(o)
+#
+#        o = receipt(tx_hash)
+#        r = self.rpc.do(o)
+#        self.assertEqual(r['status'], 1)
+#
+#        o = c.redistributions(self.address, 1, sender_address=self.accounts[0])
+#        r = self.rpc.do(o)
+#        oo = c.to_redistribution_supply(self.address, r, sender_address=self.accounts[0])
+#        rr = self.rpc.do(oo)
+#        oo = c.to_redistribution_demurrage_modifier(self.address, r, sender_address=self.accounts[0])
+#        rr = self.rpc.do(oo)
+#
+#        o = c.balance_of(self.address, self.sink_address, sender_address=self.accounts[0])
+#        r = self.rpc.do(o)
+#        balance = c.parse_balance(r)
+#
+#        self.backend.time_travel(self.start_time + self.period_seconds * 2 + 1)
+#        (tx_hash, o) = c.change_period(self.address, self.accounts[0])
+#        r = self.rpc.do(o)
+#
+#        o = receipt(tx_hash)
+#        r = self.rpc.do(o)
+#        self.assertEqual(r['status'], 1)
+#
+#        o = c.redistributions(self.address, 2, sender_address=self.accounts[0])
+#        r = self.rpc.do(o)
+#        oo = c.to_redistribution_supply(self.address, r, sender_address=self.accounts[0])
+#        rr = self.rpc.do(oo)
+#        oo = c.to_redistribution_demurrage_modifier(self.address, r, sender_address=self.accounts[0])
+#        rr = self.rpc.do(oo)
+#
+#        o = c.balance_of(self.address, self.sink_address, sender_address=self.accounts[0])
+#        r = self.rpc.do(o)
+#        balance = c.parse_balance(r)
+
+
+if __name__ == '__main__':
+    unittest.main()

python/tests/test_redistribution_unit.py

@@ -31,12 +31,12 @@ testdir = os.path.dirname(__file__)
 
 class TestRedistribution(TestDemurrageUnit):
 
+
     # TODO: move to "pure" test file when getdistribution is implemented in all contracts
-    def test_distribution(self):
+    def test_distribution_direct(self):
         nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
         c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
 
-        #demurrage = (1 - (self.tax_level / 1000000)) * (10**38)
         demurrage = (1 - (self.tax_level / 1000000)) * (10**28)
         supply = self.default_supply
 
@@ -51,21 +51,23 @@ class TestRedistribution(TestDemurrageUnit):
         nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
         c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
 
-        #demurrage = (1 - (self.tax_level / 1000000)) * (10**38)
-        demurrage = (1 - (self.tax_level / 1000000)) * (10**28)
+        demurrage = (1 - (self.tax_level / 100000)) * (10**28)
+
+        logg.debug('demurrage {}'.format(demurrage))
         supply = self.default_supply
 
-        o = c.to_redistribution(self.address, 0, demurrage, supply, 1, sender_address=self.accounts[0])
+        o = c.to_redistribution(self.address, 0, demurrage, supply, 2, sender_address=self.accounts[0])
         redistribution = self.rpc.do(o)
 
         o = c.get_distribution_from_redistribution(self.address, redistribution, self.accounts[0])
         r = self.rpc.do(o)
         distribution = c.parse_get_distribution(r)
-        expected_distribution = self.default_supply * (self.tax_level / 1000000)
+        expected_distribution = (self.default_supply * self.tax_level) / 100000
+        logg.debug('distribution {} supply {}'.format(distribution, self.default_supply))
         self.assert_within_lower(distribution, expected_distribution, 1000)
 
 
-    def test_single_step(self):
+    def test_single_step_basic(self):
         nonce_oracle = RPCNonceOracle(self.accounts[0], self.rpc)
         c = DemurrageToken(self.chain_spec, signer=self.signer, nonce_oracle=nonce_oracle)
 
@@ -81,6 +83,12 @@ class TestRedistribution(TestDemurrageUnit):
 
         expected_balance = int(mint_amount - ((self.tax_level / 1000000) * mint_amount))
 
+        o = c.balance_of(self.address, ZERO_ADDRESS, sender_address=self.accounts[0])
+        r = self.rpc.do(o)
+        balance = c.parse_balance(r)
+
+        logg.debug('balance {}'.format(balance))
+
         o = c.balance_of(self.address, self.accounts[1], sender_address=self.accounts[0])
         r = self.rpc.do(o)
         balance = c.parse_balance(r)
@@ -169,15 +177,13 @@ class TestRedistribution(TestDemurrageUnit):
 
         o = c.redistributions(self.address, 0, sender_address=self.accounts[0])
         redistribution = self.rpc.do(o)
+        logg.debug('redistribution {}'.format(redistribution))
         o = c.to_redistribution_supply(self.address, redistribution, sender_address=self.accounts[0])
         r = self.rpc.do(o)
         supply = c.parse_to_redistribution_item(r)
         o = c.to_redistribution_demurrage_modifier(self.address, redistribution, sender_address=self.accounts[0])
         r = self.rpc.do(o)
         demurrage = c.parse_to_redistribution_item(r)
-#        o = c.demurrage_amount(self.address, sender_address=self.accounts[0])
-#        r = self.rpc.do(o)
-#        demurrage = c.parse_demurrage_amount(r)
         logg.debug('\nrediistribution {}\ndemurrage {}\nsupply {}'.format(redistribution, demurrage, supply))
 
         expected_balance = int(supply * (self.tax_level / 1000000))

solidity/DemurrageTokenSingleNocap.sol

@@ -1,18 +1,24 @@
-pragma solidity > 0.6.11;
+pragma solidity >= 0.8.0;
+
 
 // SPDX-License-Identifier: GPL-3.0-or-later
-
 contract DemurrageTokenSingleCap {
 
+	struct redistributionItem {
+		uint32 period;
+		uint72 value;
+		uint104 demurrage;
+	}
+	redistributionItem[] public redistributions; // uint51(unused) | uint64(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
 	// Redistribution bit field, with associated shifts and masks
 	// (Uses sub-byte boundaries)
-	bytes32[] public redistributions; // uint51(unused) | uint64(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
-	uint8 constant shiftRedistributionPeriod 	= 0;
-	uint256 constant maskRedistributionPeriod 	= 0x00000000000000000000000000000000000000000000000000000000ffffffff; // (1 << 32) - 1
-	uint8 constant shiftRedistributionValue 	= 32;
-	uint256 constant maskRedistributionValue	= 0x00000000000000000000000000000000000000ffffffffffffffffff00000000; // ((1 << 72) - 1) << 32
-	uint8 constant shiftRedistributionDemurrage	= 104;
-	uint256 constant maskRedistributionDemurrage	= 0x0000000000ffffffffffffffffffffffffffff00000000000000000000000000; // ((1 << 20) - 1) << 140
+//	bytes32[] public redistributions; // uint51(unused) | uint64(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
+//	uint8 constant shiftRedistributionPeriod 	= 0;
+//	uint256 constant maskRedistributionPeriod 	= 0x00000000000000000000000000000000000000000000000000000000ffffffff; // (1 << 32) - 1
+//	uint8 constant shiftRedistributionValue 	= 32;
+//	uint256 constant maskRedistributionValue	= 0x00000000000000000000000000000000000000ffffffffffffffffff00000000; // ((1 << 72) - 1) << 32
+//	uint8 constant shiftRedistributionDemurrage	= 104;
+//	uint256 constant maskRedistributionDemurrage	= 0x0000000000ffffffffffffffffffffffffffff00000000000000000000000000; // ((1 << 36) - 1) << 140
 
 	// Account balances
 	mapping (address => uint256) account;
@@ -20,8 +26,6 @@ contract DemurrageTokenSingleCap {
 	// Cached demurrage amount, ppm with 38 digit resolution
 	uint128 public demurrageAmount;
 
-	// Cached demurrage period; the period for which demurrageAmount was calculated
-	//uint128 public demurragePeriod;
 	// Cached demurrage timestamp; the timestamp for which demurrageAmount was last calculated
 	uint256 public demurrageTimestamp;
 
@@ -40,10 +44,17 @@ contract DemurrageTokenSingleCap {
 	uint256 public decimals;
 
 	// Implements ERC20
-	uint256 public totalSupply;
+	//uint256 public totalSupply;
+	uint256 supply;
 
-	// Minimum amount of (demurraged) tokens an account must spend to participate in redistribution for a particular period
-	uint256 public minimumParticipantSpend;
+	// Last executed period
+	uint256 public lastPeriod;
+
+	// Last sink redistribution amount
+	uint256 public totalSink;
+
+	// Value of burnt tokens (burnt tokens do not decay)
+	uint256 public burned;
 
 	// 128 bit resolution of the demurrage divisor
 	// (this constant x 1000000 is contained within 128 bits)
@@ -71,7 +82,7 @@ contract DemurrageTokenSingleCap {
 	mapping (address => mapping (address => uint256 ) ) allowance; // holder -> spender -> amount (amount is subject to demurrage)
 
 	// Address to send unallocated redistribution tokens
-	address sinkAddress; 
+	address public sinkAddress; 
 
 	// Implements ERC20
 	event Transfer(address indexed _from, address indexed _to, uint256 _value);
@@ -94,10 +105,15 @@ contract DemurrageTokenSingleCap {
 	// Temporary event used in development, will be removed on prod
 	event Debug(bytes32 _foo);
 
+	// Emitted when tokens are burned
+	event Burn(address indexed _burner, uint256 _value);
+
 	// EIP173
 	event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); // EIP173
 
 	constructor(string memory _name, string memory _symbol, uint8 _decimals, uint128 _taxLevelMinute, uint256 _periodMinutes, address _defaultSinkAddress) public {
+		redistributionItem memory initialRedistribution;
+
 		// ACL setup
 		owner = msg.sender;
 		minter[owner] = true;
@@ -111,17 +127,13 @@ contract DemurrageTokenSingleCap {
 		demurrageTimestamp = block.timestamp;
 		periodStart = demurrageTimestamp;
 		periodDuration = _periodMinutes * 60;
-		//demurrageAmount = 100000000000000000000000000000000000000 - _taxLevelMinute; // Represents 38 decimal places, same as resolutionFactor
-		//demurrageAmount = 100000000000000000000000000000000000000;
-		demurrageAmount = 10000000000000000000000000000;
-		//demurragePeriod = 1;
+		demurrageAmount = uint128(nanoDivider) * 100;
 		taxLevel = _taxLevelMinute; // Represents 38 decimal places
-		bytes32 initialRedistribution = toRedistribution(0, demurrageAmount, 0, 1);
+		initialRedistribution = toRedistribution(0, demurrageAmount, 0, 1);
 		redistributions.push(initialRedistribution);
 
 		// Misc settings
 		sinkAddress = _defaultSinkAddress;
-		minimumParticipantSpend = 10 ** uint256(_decimals);
 	}
 
 
@@ -153,10 +165,8 @@ contract DemurrageTokenSingleCap {
 
 		baseBalance = baseBalanceOf(_account);
 
-		//periodCount = actualPeriod() - demurragePeriod; 
 		periodCount = getMinutesDelta(demurrageTimestamp);
 
-		//currentDemurragedAmount = uint128(decayBy(demurrageAmount, periodCount));
 		currentDemurragedAmount = uint128(decayBy(demurrageAmount * 10000000000, periodCount));
 
 		return (baseBalance * currentDemurragedAmount) / (nanoDivider * 1000000000000);
@@ -211,7 +221,7 @@ contract DemurrageTokenSingleCap {
 
 		changePeriod();
 		baseAmount = toBaseAmount(_amount);
-		totalSupply += _amount;
+		supply += _amount;
 		increaseBaseBalance(_beneficiary, baseAmount);
 		emit Mint(msg.sender, _beneficiary, _amount);
 		saveRedistributionSupply();
@@ -220,47 +230,82 @@ contract DemurrageTokenSingleCap {
 
 	// Deserializes the redistribution word
 	// uint95(unused) | uint20(demurrageModifier) | uint36(participants) | uint72(value) | uint32(period)
-	function toRedistribution(uint256 _participants, uint256 _demurrageModifierPpm, uint256 _value, uint256 _period) public pure returns(bytes32) {
-		bytes32 redistribution;
+//	function toRedistribution(uint256 _participants, uint256 _demurrageModifierPpm, uint256 _value, uint256 _period) public pure returns(bytes32) {
+//		bytes32 redistribution;
+//
+//		redistribution |= bytes32((_demurrageModifierPpm << shiftRedistributionDemurrage) & maskRedistributionDemurrage);
+//		redistribution |= bytes32((_value << shiftRedistributionValue) & maskRedistributionValue); 
+//		redistribution |= bytes32(_period & maskRedistributionPeriod);
+//		return redistribution;
+//	}
 
-		redistribution |= bytes32((_demurrageModifierPpm << shiftRedistributionDemurrage) & maskRedistributionDemurrage);
-		redistribution |= bytes32((_value << shiftRedistributionValue) & maskRedistributionValue); 
-		redistribution |= bytes32(_period & maskRedistributionPeriod);
+	function toRedistribution(uint256 _participants, uint256 _demurrageModifierPpm, uint256 _value, uint256 _period) public pure returns(redistributionItem memory) {
+		redistributionItem memory redistribution;
+
+		redistribution.period = uint32(_period);
+		redistribution.value = uint72(_value);
+		redistribution.demurrage = uint104(_demurrageModifierPpm);
 		return redistribution;
+
+	}
+//
+//	// Serializes the demurrage period part of the redistribution word
+//	function toRedistributionPeriod(bytes32 redistribution) public pure returns (uint256) {
+//		return uint256(redistribution) & maskRedistributionPeriod;
+//	}
+//
+
+	function toRedistributionPeriod(redistributionItem memory _redistribution) public pure returns (uint256) {
+		return uint256(_redistribution.period);
 	}
 
-	// Serializes the demurrage period part of the redistribution word
-	function toRedistributionPeriod(bytes32 redistribution) public pure returns (uint256) {
-		return uint256(redistribution) & maskRedistributionPeriod;
+//	// Serializes the supply part of the redistribution word
+//	function toRedistributionSupply(bytes32 redistribution) public pure returns (uint256) {
+//		return (uint256(redistribution) & kkRedistributionValue) >> shiftRedistributionValue;
+//	}
+	
+	function toRedistributionSupply(redistributionItem memory _redistribution) public pure returns (uint256) {
+		return uint256(_redistribution.value);
 	}
 
-	// Serializes the supply part of the redistribution word
-	function toRedistributionSupply(bytes32 redistribution) public pure returns (uint256) {
-		return (uint256(redistribution) & maskRedistributionValue) >> shiftRedistributionValue;
+//
+//	// Serializes the number of participants part of the redistribution word
+//	function toRedistributionDemurrageModifier(bytes32 redistribution) public pure returns (uint256) {
+//		return (uint256(redistribution) & maskRedistributionDemurrage) >> shiftRedistributionDemurrage;
+//	}
+
+	function toRedistributionDemurrageModifier(redistributionItem memory _redistribution) public pure returns (uint256) {
+		return uint256(_redistribution.demurrage);
 	}
 
-	// Serializes the number of participants part of the redistribution word
-	function toRedistributionDemurrageModifier(bytes32 redistribution) public pure returns (uint256) {
-		return (uint256(redistribution) & maskRedistributionDemurrage) >> shiftRedistributionDemurrage;
-	}
 
 	// Client accessor to the redistributions array length
 	function redistributionCount() public view returns (uint256) {
 		return redistributions.length;
 	}
-
-	// Save the current total supply amount to the current redistribution period
+//
+//	// Save the current total supply amount to the current redistribution period
+//	function saveRedistributionSupply() private returns (bool) {
+//		uint256 currentRedistribution;
+//		uint256 grownSupply;
+//
+//		grownSupply = totalSupply();
+//		currentRedistribution = uint256(redistributions[redistributions.length-1]);
+//		currentRedistribution &= (~maskRedistributionValue);
+//		currentRedistribution |= (grownSupply << shiftRedistributionValue);
+//
+//		redistributions[redistributions.length-1] = bytes32(currentRedistribution);
+//		return true;
+//	}
 	function saveRedistributionSupply() private returns (bool) {
-		uint256 currentRedistribution;
+		redistributionItem memory currentRedistribution;
 		uint256 grownSupply;
 
-		//grownSupply = growBy(totalSupply, 1);
-		grownSupply = totalSupply;
-		currentRedistribution = uint256(redistributions[redistributions.length-1]);
-		currentRedistribution &= (~maskRedistributionValue);
-		currentRedistribution |= (grownSupply << shiftRedistributionValue);
+		grownSupply = totalSupply();
+		currentRedistribution = redistributions[redistributions.length-1];
+		currentRedistribution.value = uint72(grownSupply);
 
-		redistributions[redistributions.length-1] = bytes32(currentRedistribution);
+		redistributions[redistributions.length-1] = currentRedistribution;
 		return true;
 	}
 
@@ -269,15 +314,16 @@ contract DemurrageTokenSingleCap {
 		return uint128((block.timestamp - periodStart) / periodDuration + 1);
 	}
 
-	// Add an entered demurrage period to the redistribution array
-	function checkPeriod() private view returns (bytes32) {
-		bytes32 lastRedistribution;
+	// Retrieve next redistribution if the period threshold has been crossed
+	function checkPeriod() private view returns (redistributionItem memory) {
+		redistributionItem memory lastRedistribution;
+		redistributionItem memory emptyRedistribution;
 		uint256 currentPeriod;
 
-		lastRedistribution =  redistributions[redistributions.length-1];
+		lastRedistribution =  redistributions[lastPeriod];
 		currentPeriod = this.actualPeriod();
 		if (currentPeriod <= toRedistributionPeriod(lastRedistribution)) {
-			return bytes32(0x00);
+			return emptyRedistribution;
 		}
 		return lastRedistribution;
 	}
@@ -285,12 +331,11 @@ contract DemurrageTokenSingleCap {
 	function getDistribution(uint256 _supply, uint256 _demurrageAmount) public view returns (uint256) {
 		uint256 difference;
 
-		//difference = _supply * (resolutionFactor - _demurrageAmount); //(nanoDivider - ((resolutionFactor - _demurrageAmount) / nanoDivider));
-		difference = _supply * (resolutionFactor - (_demurrageAmount * 10000000000)); //(nanoDivider - ((resolutionFactor - _demurrageAmount) / nanoDivider));
+		difference = _supply * (resolutionFactor - (_demurrageAmount * 10000000000));
 		return difference / resolutionFactor;
 	}
 
-	function getDistributionFromRedistribution(bytes32 _redistribution) public returns (uint256) {
+	function getDistributionFromRedistribution(redistributionItem memory _redistribution) public returns (uint256) {
 		uint256 redistributionSupply;
 		uint256 redistributionDemurrage;
 
@@ -300,11 +345,15 @@ contract DemurrageTokenSingleCap {
 	}
 
 	// Returns the amount sent to the sink address
-	function applyDefaultRedistribution(bytes32 _redistribution) private returns (uint256) {
+	function applyDefaultRedistribution(redistributionItem memory _redistribution) private returns (uint256) {
 		uint256 unit;
+		uint256 baseUnit;
 	
 		unit = getDistributionFromRedistribution(_redistribution);	
-		increaseBaseBalance(sinkAddress, toBaseAmount(unit));
+		baseUnit = toBaseAmount(unit) - totalSink;
+		increaseBaseBalance(sinkAddress, baseUnit);
+		lastPeriod += 1;
+		totalSink += baseUnit;
 		return unit;
 	}
 
@@ -319,13 +368,9 @@ contract DemurrageTokenSingleCap {
 	}
 
 	function applyDemurrageLimited(uint256 _rounds) public returns (bool) {
-		//uint128 epochPeriodCount;
 		uint256 periodCount;
 		uint256 lastDemurrageAmount;
 
-		//epochPeriodCount = actualPeriod();
-		//periodCount = epochPeriodCount - demurragePeriod;
-
 		periodCount = getMinutesDelta(demurrageTimestamp);
 		if (periodCount == 0) {
 			return false;
@@ -355,37 +400,46 @@ contract DemurrageTokenSingleCap {
 		return (block.timestamp - _target) / 60;
 	}
 
+	function isEmptyRedistribution(redistributionItem memory _redistribution) public pure returns(bool) {
+		if (_redistribution.period > 0) {
+			return false;
+		}
+		if (_redistribution.value > 0) {
+			return false;
+		}
+		if (_redistribution.demurrage > 0) {
+			return false;
+		}
+		return true;
+	}
+
 	// Recalculate the demurrage modifier for the new period
+	// Note that the supply for the consecutive period will be taken at the time of code execution, and thus not necessarily at the time when the redistribution period threshold was crossed.
 	function changePeriod() public returns (bool) {
-		bytes32 currentRedistribution;
-		bytes32 nextRedistribution;
+		redistributionItem memory currentRedistribution;
+		redistributionItem memory nextRedistribution;
+		redistributionItem memory lastRedistribution;
 		uint256 currentPeriod;
-		uint256 currentDemurrageAmount;
+		uint256 lastDemurrageAmount;
 		uint256 nextRedistributionDemurrage;
 		uint256 demurrageCounts;
-		uint256 periodTimestamp;
 		uint256 nextPeriod;
 
 		applyDemurrage();
 		currentRedistribution = checkPeriod();
-		if (currentRedistribution == bytes32(0x00)) {
+		if (isEmptyRedistribution(currentRedistribution)) {
 			return false;
 		}
 
+		// calculate the decay from previous redistributino
+		lastRedistribution = redistributions[lastPeriod];
 		currentPeriod = toRedistributionPeriod(currentRedistribution);
 		nextPeriod = currentPeriod + 1;
-		periodTimestamp = getPeriodTimeDelta(currentPeriod);
-
-		currentDemurrageAmount = demurrageAmount; 
-
-		demurrageCounts = demurrageCycles(periodTimestamp);
-		if (demurrageCounts > 0) {
-			nextRedistributionDemurrage = growBy(currentDemurrageAmount, demurrageCounts);
-		} else {
-			nextRedistributionDemurrage = currentDemurrageAmount;
-		}
-		
-		nextRedistribution = toRedistribution(0, nextRedistributionDemurrage, totalSupply, nextPeriod);
+		lastDemurrageAmount = toRedistributionDemurrageModifier(lastRedistribution);
+		demurrageCounts = periodDuration / 60;
+		nextRedistributionDemurrage = decayBy(lastDemurrageAmount, demurrageCounts);
+	
+		nextRedistribution = toRedistribution(0, nextRedistributionDemurrage, totalSupply(), nextPeriod);
 		redistributions.push(nextRedistribution);
 
 		applyDefaultRedistribution(nextRedistribution);
@@ -394,18 +448,18 @@ contract DemurrageTokenSingleCap {
 	}
 
 	// Reverse a value reduced by demurrage by the given period to its original value
-	function growBy(uint256 _value, uint256 _period) public view returns (uint256) {
-		uint256 valueFactor;
-		uint256 truncatedTaxLevel;
-	      
-		valueFactor = growthResolutionFactor;
-		truncatedTaxLevel = taxLevel / nanoDivider;
-
-		for (uint256 i = 0; i < _period; i++) {
-			valueFactor = valueFactor + ((valueFactor * truncatedTaxLevel) / growthResolutionFactor);
-		}
-		return (valueFactor * _value) / growthResolutionFactor;
-	}
+//	function growBy(uint256 _value, uint256 _period) public view returns (uint256) {
+//		uint256 valueFactor;
+//		uint256 truncatedTaxLevel;
+//	      
+//		valueFactor = growthResolutionFactor;
+//		truncatedTaxLevel = taxLevel / nanoDivider;
+//
+//		for (uint256 i = 0; i < _period; i++) {
+//			valueFactor = valueFactor + ((valueFactor * truncatedTaxLevel) / growthResolutionFactor);
+//		}
+//		return (valueFactor * _value) / growthResolutionFactor;
+//	}
 
 	// Calculate a value reduced by demurrage by the given period
 	function decayBy(uint256 _value, uint256 _period) public view returns (uint256) {
@@ -423,7 +477,6 @@ contract DemurrageTokenSingleCap {
 
 	// Inflates the given amount according to the current demurrage modifier
 	function toBaseAmount(uint256 _value) public view returns (uint256) {
-		//return (_value * resolutionFactor) / demurrageAmount;
 		return (_value * resolutionFactor) / (demurrageAmount * 10000000000);
 	}
 
@@ -431,14 +484,45 @@ contract DemurrageTokenSingleCap {
 	function approve(address _spender, uint256 _value) public returns (bool) {
 		uint256 baseValue;
 
+		if (allowance[msg.sender][_spender] > 0) {
+			require(_value == 0, 'ZERO_FIRST');
+		}
+		
 		changePeriod();
 
 		baseValue = toBaseAmount(_value);
-		allowance[msg.sender][_spender] += baseValue;
+		allowance[msg.sender][_spender] = baseValue;
 		emit Approval(msg.sender, _spender, _value);
 		return true;
 	}
 
+	// Reduce allowance by amount
+	function decreaseAllowance(address _spender, uint256 _value) public returns (bool) {
+		uint256 baseValue;
+
+		baseValue = toBaseAmount(_value);
+		require(allowance[msg.sender][_spender] >= baseValue);
+		
+		changePeriod();
+
+		allowance[msg.sender][_spender] -= baseValue;
+		emit Approval(msg.sender, _spender, allowance[msg.sender][_spender]);
+		return true;
+	}
+
+	// Increase allowance by amount
+	function increaseAllowance(address _spender, uint256 _value) public returns (bool) {
+		uint256 baseValue;
+
+		changePeriod();
+
+		baseValue = toBaseAmount(_value);
+
+		allowance[msg.sender][_spender] += baseValue;
+		emit Approval(msg.sender, _spender, allowance[msg.sender][_spender]);
+		return true;
+	}
+
 	// Implements ERC20, triggers tax and/or redistribution
 	function transfer(address _to, uint256 _value) public returns (bool) {
 		uint256 baseValue;
@@ -462,7 +546,9 @@ contract DemurrageTokenSingleCap {
 		baseValue = toBaseAmount(_value);
 		require(allowance[_from][msg.sender] >= baseValue);
 
+		allowance[_from][msg.sender] -= baseValue;
 		result = transferBase(_from, _to, baseValue);
+
 		emit Transfer(_from, _to, _value);
 		return result;
 	}
@@ -474,7 +560,6 @@ contract DemurrageTokenSingleCap {
 		decreaseBaseBalance(_from, _value);
 		increaseBaseBalance(_to, _value);
 
-		//period = actualPeriod();
 		return true;
 	}
 
@@ -495,6 +580,29 @@ contract DemurrageTokenSingleCap {
 		emit OwnershipTransferred(oldOwner, owner);
 	}
 
+	// Explicitly and irretrievably burn tokens
+	// Only token minters can burn tokens
+	function burn(uint256 _value) public {
+		require(minter[msg.sender]);
+		require(_value <= account[msg.sender]);
+		uint256 _delta = toBaseAmount(_value);
+
+		applyDemurrage();
+		decreaseBaseBalance(msg.sender, _delta);
+		burned += _value;
+		emit Burn(msg.sender, _value);
+	}
+
+	// Implements ERC20
+	function totalSupply() public view returns (uint256) {
+		return supply - burned;
+	}
+
+	// Return total number of burned tokens
+	function totalBurned() public view returns (uint256) {
+		return burned;
+	}
+
 	// Implements EIP165
 	function supportsInterface(bytes4 _sum) public pure returns (bool) {
 		if (_sum == 0xc6bb4b70) { // ERC20

solidity/Makefile

@@ -32,7 +32,15 @@ test: all
 	python ../python/tests/test_redistribution.py
 	python ../python/tests/test_pure.py
 
-install: all
+#install: all
+install: single_nocap
+	#cp -v DemurrageToken*.{json,bin} ../python/erc20_demurrage_token/data/
+	cp -v DemurrageTokenSingleNocap.json ../python/erc20_demurrage_token/data/
+	cp -v DemurrageTokenSingleNocap.bin ../python/erc20_demurrage_token/data/
+
+install-broken: all
 	cp -v DemurrageToken*.{json,bin} ../python/erc20_demurrage_token/data/
+
+
 	
 .PHONY: test install