implement spectest decorator, update attestation tests

test_libs/pyspec/tests/block_processing/test_process_attestation.py

@@ -8,8 +8,7 @@ from eth2spec.phase0.state_transition import (
 )
 from eth2spec.phase0.spec import (
     get_current_epoch,
-    process_attestation,
-    slot_to_epoch,
+    process_attestation
 )
 from tests.helpers import (
     build_empty_block_for_next_slot,
@@ -18,63 +17,75 @@ from tests.helpers import (
     next_slot,
 )
 
-
-# mark entire file as 'attestations'
-pytestmark = pytest.mark.attestations
+from tests.utils import spectest
+from tests.context import with_state
 
 
 def run_attestation_processing(state, attestation, valid=True):
     """
-    Run ``process_attestation`` returning the pre and post state.
+    Run ``process_attestation``, yielding pre-state ('pre'), attestation ('attestation'), and post-state ('post').
     If ``valid == False``, run expecting ``AssertionError``
     """
-    post_state = deepcopy(state)
+    # yield pre-state
+    yield 'pre', state
 
+    yield 'attestation', attestation
+
+    # If the attestation is invalid, processing is aborted, and there is no post-state.
     if not valid:
         with pytest.raises(AssertionError):
-            process_attestation(post_state, attestation)
-        return state, None
+            process_attestation(state, attestation)
+        yield 'post', None
+        return
 
-    process_attestation(post_state, attestation)
+    current_epoch_count = len(state.current_epoch_attestations)
+    previous_epoch_count = len(state.previous_epoch_attestations)
 
-    current_epoch = get_current_epoch(state)
-    if attestation.data.target_epoch == current_epoch:
-        assert len(post_state.current_epoch_attestations) == len(state.current_epoch_attestations) + 1
+    # process attestation
+    process_attestation(state, attestation)
+
+    # Make sure the attestation has been processed
+    if attestation.data.target_epoch == get_current_epoch(state):
+        assert len(state.current_epoch_attestations) == current_epoch_count + 1
     else:
-        assert len(post_state.previous_epoch_attestations) == len(state.previous_epoch_attestations) + 1
+        assert len(state.previous_epoch_attestations) == previous_epoch_count + 1
 
-    return state, post_state
+    # yield post-state
+    yield 'post', state
 
 
+# shorthand for decorating @with_state @spectest()
+def attestation_test(fn):
+    return with_state(spectest()(fn))
+
+
+@attestation_test
 def test_success(state):
     attestation = get_valid_attestation(state)
     state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
 
-    pre_state, post_state = run_attestation_processing(state, attestation)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation)
 
 
+@attestation_test
 def test_success_prevous_epoch(state):
     attestation = get_valid_attestation(state)
     block = build_empty_block_for_next_slot(state)
     block.slot = state.slot + spec.SLOTS_PER_EPOCH
     state_transition(state, block)
 
-    pre_state, post_state = run_attestation_processing(state, attestation)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation)
 
 
+@attestation_test
 def test_before_inclusion_delay(state):
     attestation = get_valid_attestation(state)
     # do not increment slot to allow for inclusion delay
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)
 
 
+@attestation_test
 def test_after_epoch_slots(state):
     attestation = get_valid_attestation(state)
     block = build_empty_block_for_next_slot(state)
@@ -82,44 +93,40 @@ def test_after_epoch_slots(state):
     block.slot = state.slot + spec.SLOTS_PER_EPOCH + 1
     state_transition(state, block)
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)
 
 
+@attestation_test
 def test_bad_source_epoch(state):
     attestation = get_valid_attestation(state)
     state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
 
     attestation.data.source_epoch += 10
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)
 
 
+@attestation_test
 def test_bad_source_root(state):
     attestation = get_valid_attestation(state)
     state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
 
     attestation.data.source_root = b'\x42' * 32
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)
 
 
+@attestation_test
 def test_non_zero_crosslink_data_root(state):
     attestation = get_valid_attestation(state)
     state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
 
     attestation.data.crosslink_data_root = b'\x42' * 32
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)
 
 
+@attestation_test
 def test_bad_previous_crosslink(state):
     next_epoch(state)
     attestation = get_valid_attestation(state)
@@ -128,28 +135,24 @@ def test_bad_previous_crosslink(state):
 
     state.current_crosslinks[attestation.data.shard].epoch += 10
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)
 
 
+@attestation_test
 def test_non_empty_custody_bitfield(state):
     attestation = get_valid_attestation(state)
     state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
 
     attestation.custody_bitfield = deepcopy(attestation.aggregation_bitfield)
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)
 
 
+@attestation_test
 def test_empty_aggregation_bitfield(state):
     attestation = get_valid_attestation(state)
     state.slot += spec.MIN_ATTESTATION_INCLUSION_DELAY
 
     attestation.aggregation_bitfield = b'\x00' * len(attestation.aggregation_bitfield)
 
-    pre_state, post_state = run_attestation_processing(state, attestation, False)
-
-    return pre_state, attestation, post_state
+    yield from run_attestation_processing(state, attestation, False)

test_libs/pyspec/tests/conftest.py

@@ -3,10 +3,6 @@ import pytest
 from eth2spec.phase0 import spec
 from preset_loader import loader
 
-from .helpers import (
-    create_genesis_state,
-)
-
 
 def pytest_addoption(parser):
     parser.addoption(
@@ -19,18 +15,3 @@ def config(request):
     config_name = request.config.getoption("--config")
     presets = loader.load_presets('../../configs/', config_name)
     spec.apply_constants_preset(presets)
-
-
-@pytest.fixture
-def num_validators(config):
-    return spec.SLOTS_PER_EPOCH * 8
-
-
-@pytest.fixture
-def deposit_data_leaves():
-    return list()
-
-
-@pytest.fixture
-def state(num_validators, deposit_data_leaves):
-    return create_genesis_state(num_validators, deposit_data_leaves)

test_libs/pyspec/tests/context.py

@@ -0,0 +1,10 @@
+
+from eth2spec.phase0 import spec
+from tests.utils import with_args
+
+from .helpers import (
+    create_genesis_state,
+)
+
+# Provides a genesis state as first argument to the function decorated with this
+with_state = with_args(lambda: [create_genesis_state(spec.SLOTS_PER_EPOCH * 8, list())])

test_libs/pyspec/tests/utils.py

@@ -0,0 +1,46 @@
+from eth2spec.debug.encode import encode
+
+
+def spectest(description: str = None):
+    def runner(fn):
+        # this wraps the function, to hide that the function actually yielding data.
+        def entry(*args, **kw):
+            # check generator mode, may be None/else.
+            # "pop" removes it, so it is not passed to the inner function.
+            if kw.pop('generator_mode', False) is True:
+                out = {}
+                if description is None:
+                    # fall back on function name for test description
+                    name = fn.__name__
+                    if name.startswith('test_'):
+                        name = name[5:]
+                    out['description'] = name
+                else:
+                    # description can be explicit
+                    out['description'] = description
+                # put all generated data into a dict.
+                for data in fn(*args, **kw):
+                    # If there is a type argument, encode it as that type.
+                    if len(data) == 3:
+                        (key, value, typ) = data
+                        out[key] = encode(value, typ)
+                    else:
+                        # Otherwise, just put the raw value.
+                        (key, value) = data
+                        out[key] = value
+                return out
+            else:
+                # just complete the function, ignore all yielded data, we are not using it
+                for _ in fn(*args, **kw):
+                    continue
+        return entry
+    return runner
+
+
+def with_args(create_args):
+    def runner(fn):
+        # this wraps the function, to hide that the function actually yielding data.
+        def entry(*args, **kw):
+            return fn(*(create_args() + list(args)), **kw)
+        return entry
+    return runner