new process-slashings tests, and epoch processing bugfix with transit…

…ion-to-excl not working when not yielded from

test_libs/pyspec/eth2spec/test/phase_0/epoch_processing/run_epoch_process_base.py

@@ -12,13 +12,9 @@
 ]
 
 
-def run_epoch_processing_to(spec, state, process_name: str, exclusive=False):
+def run_epoch_processing_to(spec, state, process_name: str):
     """
-    Run the epoch processing functions up to ``process_name``.
-    If ``exclusive`` is True, the process itself will not be ran.
-    If ``exclusive`` is False (default), this function yields:
-      - pre-state ('pre'), state before calling ``process_name``
-      - post-state ('post'), state after calling ``process_name``
+    Processes to the next epoch transition, up to, but not including, the sub-transition named ``process_name``
     """
     slot = state.slot + (spec.SLOTS_PER_EPOCH - state.slot % spec.SLOTS_PER_EPOCH)
 
@@ -36,7 +32,14 @@ def run_epoch_processing_to(spec, state, process_name: str, exclusive=False):
         if hasattr(spec, name):
             getattr(spec, name)(state)
 
-    if not exclusive:
-        yield 'pre', state
-        getattr(spec, process_name)(state)
-        yield 'post', state
+
+def run_epoch_processing_with(spec, state, process_name: str):
+    """
+    Processes to the next epoch transition, up to and including the sub-transition named ``process_name``
+      - pre-state ('pre'), state before calling ``process_name``
+      - post-state ('post'), state after calling ``process_name``
+    """
+    run_epoch_processing_to(spec, state, process_name)
+    yield 'pre', state
+    getattr(spec, process_name)(state)
+    yield 'post', state

test_libs/pyspec/eth2spec/test/phase_0/epoch_processing/test_process_crosslinks.py

@@ -12,11 +12,11 @@
     get_valid_attestation,
     sign_attestation,
 )
-from eth2spec.test.phase_0.epoch_processing.run_epoch_process_base import run_epoch_processing_to
+from eth2spec.test.phase_0.epoch_processing.run_epoch_process_base import run_epoch_processing_with
 
 
 def run_process_crosslinks(spec, state):
-    yield from run_epoch_processing_to(spec, state, 'process_crosslinks')
+    yield from run_epoch_processing_with(spec, state, 'process_crosslinks')
 
 
 @with_all_phases

test_libs/pyspec/eth2spec/test/phase_0/epoch_processing/test_process_final_updates.py

@@ -1,9 +1,11 @@
 from eth2spec.test.context import spec_state_test, with_all_phases
-from eth2spec.test.phase_0.epoch_processing.run_epoch_process_base import run_epoch_processing_to
+from eth2spec.test.phase_0.epoch_processing.run_epoch_process_base import (
+    run_epoch_processing_with, run_epoch_processing_to
+)
 
 
 def run_process_final_updates(spec, state):
-    yield from run_epoch_processing_to(spec, state, 'process_final_updates')
+    yield from run_epoch_processing_with(spec, state, 'process_final_updates')
 
 
 @with_all_phases

test_libs/pyspec/eth2spec/test/phase_0/epoch_processing/test_process_registry_updates.py

@@ -1,10 +1,10 @@
 from eth2spec.test.helpers.state import next_epoch
 from eth2spec.test.context import spec_state_test, with_all_phases
-from eth2spec.test.phase_0.epoch_processing.run_epoch_process_base import run_epoch_processing_to
+from eth2spec.test.phase_0.epoch_processing.run_epoch_process_base import run_epoch_processing_with
 
 
 def run_process_registry_updates(spec, state):
-    yield from run_epoch_processing_to(spec, state, 'process_registry_updates')
+    yield from run_epoch_processing_with(spec, state, 'process_registry_updates')
 
 
 def mock_deposit(spec, state, index):

test_libs/pyspec/eth2spec/test/phase_0/epoch_processing/test_process_slashings.py

@@ -0,0 +1,121 @@
+from eth2spec.test.context import spec_state_test, with_all_phases
+from eth2spec.test.phase_0.epoch_processing.run_epoch_process_base import (
+    run_epoch_processing_with, run_epoch_processing_to
+)
+
+
+def run_process_slashings(spec, state):
+    yield from run_epoch_processing_with(spec, state, 'process_slashings')
+
+
+def slash_validators(spec, state, indices, out_epochs):
+    total_slashed_balance = 0
+    for i, out_epoch in zip(indices, out_epochs):
+        v = state.validators[i]
+        v.slashed = True
+        spec.initiate_validator_exit(state, i)
+        v.withdrawable_epoch = out_epoch
+        total_slashed_balance += v.effective_balance
+
+    state.slashed_balances[
+        spec.get_current_epoch(state) % spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR
+    ] = total_slashed_balance
+
+
+@with_all_phases
+@spec_state_test
+def test_max_penalties(spec, state):
+    slashed_count = (len(state.validators) // 3) + 1
+    out_epoch = spec.get_current_epoch(state) + (spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR // 2)
+
+    slashed_indices = list(range(slashed_count))
+    slash_validators(spec, state, slashed_indices, [out_epoch] * slashed_count)
+
+    total_balance = spec.get_total_active_balance(state)
+    total_penalties = state.slashed_balances[spec.get_current_epoch(state) % spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR]
+
+    assert total_balance // 3 <= total_penalties
+
+    yield from run_process_slashings(spec, state)
+
+    for i in slashed_indices:
+        assert state.balances[i] == 0
+
+
+@with_all_phases
+@spec_state_test
+def test_min_penalties(spec, state):
+    # run_epoch_processing_to(spec, state, 'process_slashings', exclusive=True)
+
+    # Just the bare minimum for this one validator
+    pre_balance = state.balances[0] = state.validators[0].effective_balance = spec.EJECTION_BALANCE
+    # All the other validators get the maximum.
+    for i in range(1, len(state.validators)):
+        state.validators[i].effective_balance = state.balances[i] = spec.MAX_EFFECTIVE_BALANCE
+
+    out_epoch = spec.get_current_epoch(state) + (spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR // 2)
+
+    slash_validators(spec, state, [0], [out_epoch])
+
+    total_balance = spec.get_total_active_balance(state)
+    total_penalties = state.slashed_balances[spec.get_current_epoch(state) % spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR]
+
+    # we are testing the minimum here, i.e. get slashed (effective_balance / MIN_SLASHING_PENALTY_QUOTIENT)
+    assert total_penalties * 3 / total_balance < 1 / spec.MIN_SLASHING_PENALTY_QUOTIENT
+
+    yield from run_process_slashings(spec, state)
+
+    assert state.balances[0] == pre_balance - (pre_balance // spec.MIN_SLASHING_PENALTY_QUOTIENT)
+
+
+@with_all_phases
+@spec_state_test
+def test_scaled_penalties(spec, state):
+    # skip to next epoch
+    state.slot = spec.SLOTS_PER_EPOCH
+
+    # Also mock some previous slashings, so that we test to have the delta in the penalties computation.
+    for i in range(spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR):
+        state.slashed_balances[i] = spec.MAX_EFFECTIVE_BALANCE * 3
+
+    # Mock the very last one (which is to be used for the delta balance computation) to be different.
+    # To enforce the client test runner to correctly get this one from the array, not the others.
+    prev_penalties = state.slashed_balances[
+        (spec.get_current_epoch(state) + 1) % spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR
+    ] = spec.MAX_EFFECTIVE_BALANCE * 2
+
+    slashed_count = len(state.validators) // 4
+
+    assert slashed_count > 10
+
+    # make the balances non-uniform.
+    # Otherwise it would just be a simple 3/4 balance slashing. Test the per-validator scaled penalties.
+    for i in range(10):
+        state.validators[i].effective_balance += spec.EFFECTIVE_BALANCE_INCREMENT * 4
+        state.balances[i] += spec.EFFECTIVE_BALANCE_INCREMENT * 4
+
+    total_balance = spec.get_total_active_balance(state)
+
+    out_epoch = spec.get_current_epoch(state) + (spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR // 2)
+
+    slashed_indices = list(range(slashed_count))
+
+    # Process up to the sub-transition, then Hi-jack and get the balances.
+    # We just want to test the slashings.
+    # But we are not interested in the other balance changes during the same epoch transition.
+    run_epoch_processing_to(spec, state, 'process_slashings')
+    pre_slash_balances = list(state.balances)
+
+    slash_validators(spec, state, slashed_indices, [out_epoch] * slashed_count)
+
+    yield 'pre', state
+    spec.process_slashings(state)
+    yield 'post', state
+
+    total_penalties = state.slashed_balances[spec.get_current_epoch(state) % spec.EPOCHS_PER_SLASHED_BALANCES_VECTOR]
+    total_penalties -= prev_penalties
+
+    for i in slashed_indices:
+        v = state.validators[i]
+        penalty = v.effective_balance * total_penalties * 3 // total_balance
+        assert state.balances[i] == pre_slash_balances[i] - penalty