Add test for arbitrary account demurrage honoring burn amount

Runaway redistribution

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

python/CHANGELOG

@@ -1,3 +1,7 @@
+- 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/runnable/apply.py

@@ -11,6 +11,8 @@ import os
 import json
 import argparse
 import logging
+import datetime
+import math
 
 # external imports
 import confini
@@ -25,10 +27,16 @@ from chainlib.eth.gas import (
         RPCGasOracle,
         OverrideGasOracle,
         )
+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
 import chainlib.eth.cli
+from hexathon import to_int as hex_to_int
 
 # local imports
 import erc20_demurrage_token
@@ -47,8 +55,11 @@ config_dir = os.path.join(data_dir, 'config')
 
 arg_flags = chainlib.eth.cli.argflag_std_write | chainlib.eth.cli.Flag.EXEC
 argparser = chainlib.eth.cli.ArgumentParser(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)
+config.add(args.steps, '_STEPS', False)
+logg.debug('config loaded:\n{}'.format(config))
 
 wallet = chainlib.eth.cli.Wallet()
 wallet.from_config(config)
@@ -60,30 +71,73 @@ chain_spec = ChainSpec.from_chain_str(config.get('CHAIN_SPEC'))
 
 
 def main():
-    signer = rpc.get_signer()
-    signer_address = rpc.get_sender_address()
+    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)
+
+    o = block_by_number(block_start_number)
+    r = conn.do(o)
+
+    block_start = Block(r)
+    block_start_timestamp = block_start.timestamp
+    block_start_datetime = datetime.datetime.fromtimestamp(block_start_timestamp)
 
     gas_oracle = rpc.get_gas_oracle()
-    nonce_oracle = rpc.get_nonce_oracle()
+    c = DemurrageToken(chain_spec, gas_oracle=gas_oracle)
+    o = c.demurrage_timestamp(config.get('_EXEC_ADDRESS'))
+    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']
+    demurrage_timestamp = None
+    try:
+        demurrage_timestamp = hex_to_int(r)
+    except TypeError:
+        demurrage_timestamp = int(r)
+    demurrage_datetime = datetime.datetime.fromtimestamp(demurrage_timestamp)
 
-            print(address)
-        else:
+    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 = rpc.get_signer()
+        signer_address = rpc.get_sender_address()
+
+        nonce_oracle = rpc.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 config.get('_RPC_SEND'):
             print(tx_hash_hex)
+            conn.do(o)
+            if config.get('_WAIT_ALL') or (i == rounds - 1 and 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)
+        else:
+            print(o)
 
-    else:
-        print(o)
 
 
 if __name__ == '__main__':

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 = {}
@@ -146,6 +155,33 @@ 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()
@@ -380,6 +416,10 @@ 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)
 
@@ -513,6 +553,7 @@ 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 +577,8 @@ 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

@@ -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)
@@ -101,7 +102,12 @@ class TestDemurrage(EthTesterCase):
 #        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
@@ -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~=0.4.6
+eth-erc20~=0.5.1
+funga-eth~=0.6.0

python/run_tests.sh

@@ -6,7 +6,8 @@ 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
@@ -14,13 +15,20 @@ for m in ${modes[@]}; do
 	ERC20_DEMURRAGE_TOKEN_TEST_MODE=$m python tests/test_single.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 = 0.1.1
 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_burn.py

@@ -0,0 +1,195 @@
+# 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 TestDemurrageDefault
+
+logging.basicConfig(level=logging.DEBUG)
+logg = logging.getLogger()
+
+testdir = os.path.dirname(__file__)
+
+
+class TestBurn(TestDemurrageDefault):
+
+    def test_burn_basic(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], 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)
+
+
+    def test_burned_redistribution(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], 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)
+
+
+
+    def test_burned_other_redistribution(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], 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?
+
+
+if __name__ == '__main__':
+    unittest.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 +1,185 @@
+# 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.DEBUG)
+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 * 10))
+
+        for i in range(1, 11):
+            logg.debug('checking period {}'.format(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)
+
+        i = 10
+        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_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)
@@ -175,9 +183,6 @@ class TestRedistribution(TestDemurrageUnit):
         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

@@ -1,7 +1,6 @@
 pragma solidity > 0.6.11;
 
 // SPDX-License-Identifier: GPL-3.0-or-later
-
 contract DemurrageTokenSingleCap {
 
 	// Redistribution bit field, with associated shifts and masks
@@ -20,8 +19,6 @@ 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 +37,17 @@ 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 +75,7 @@ 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);
@@ -94,6 +98,9 @@ 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
 
@@ -111,17 +118,13 @@ 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);
 		redistributions.push(initialRedistribution);
 
 		// Misc settings
 		sinkAddress = _defaultSinkAddress;
-		minimumParticipantSpend = 10 ** uint256(_decimals);
 	}
 
 
@@ -153,10 +156,8 @@ 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 +212,7 @@ contract DemurrageTokenSingleCap {
 
 		changePeriod();
 		baseAmount = toBaseAmount(_amount);
-		totalSupply += _amount;
+		supply += _amount;
 		increaseBaseBalance(_beneficiary, baseAmount);
 		emit Mint(msg.sender, _beneficiary, _amount);
 		saveRedistributionSupply();
@@ -254,8 +255,7 @@ contract DemurrageTokenSingleCap {
 		uint256 currentRedistribution;
 		uint256 grownSupply;
 
-		//grownSupply = growBy(totalSupply, 1);
-		grownSupply = totalSupply;
+		grownSupply = totalSupply();
 		currentRedistribution = uint256(redistributions[redistributions.length-1]);
 		currentRedistribution &= (~maskRedistributionValue);
 		currentRedistribution |= (grownSupply << shiftRedistributionValue);
@@ -274,7 +274,7 @@ contract DemurrageTokenSingleCap {
 		bytes32 lastRedistribution;
 		uint256 currentPeriod;
 
-		lastRedistribution =  redistributions[redistributions.length-1];
+		lastRedistribution =  redistributions[lastPeriod];
 		currentPeriod = this.actualPeriod();
 		if (currentPeriod <= toRedistributionPeriod(lastRedistribution)) {
 			return bytes32(0x00);
@@ -285,8 +285,7 @@ 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;
 	}
 
@@ -302,9 +301,13 @@ contract DemurrageTokenSingleCap {
 	// Returns the amount sent to the sink address
 	function applyDefaultRedistribution(bytes32 _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 +322,9 @@ 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;
@@ -385,7 +384,7 @@ contract DemurrageTokenSingleCap {
 			nextRedistributionDemurrage = currentDemurrageAmount;
 		}
 		
-		nextRedistribution = toRedistribution(0, nextRedistributionDemurrage, totalSupply, nextPeriod);
+		nextRedistribution = toRedistribution(0, nextRedistributionDemurrage, totalSupply(), nextPeriod);
 		redistributions.push(nextRedistribution);
 
 		applyDefaultRedistribution(nextRedistribution);
@@ -423,7 +422,6 @@ 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);
 	}
 
@@ -474,7 +472,6 @@ contract DemurrageTokenSingleCap {
 		decreaseBaseBalance(_from, _value);
 		increaseBaseBalance(_to, _value);
 
-		//period = actualPeriod();
 		return true;
 	}
 
@@ -495,6 +492,28 @@ contract DemurrageTokenSingleCap {
 		emit OwnershipTransferred(oldOwner, owner);
 	}
 
+	// Explicitly and irretrievably 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