def step(self, dependency_states, step_context):
# Request default Variants for the subject, so that if there are any we can propagate
# them to task nodes.
variants = self.variants
variants_node = self._variants_node()
if variants_node:
dep_state = dependency_states.get(variants_node, None)
if dep_state is None or type(dep_state) == Waiting:
return Waiting([variants_node])
elif type(dep_state) == Return:
# A subject's variants are overridden by any dependent's requested variants, so
# we merge them left to right here.
variants = Variants.merge(dep_state.value.default.items(), variants)
# If there is a variant_key, see whether it has been configured.
variant_value = None
if self.variant_key:
variant_values = [value for key, value in variants
if key == self.variant_key] if variants else None
if not variant_values:
# Select cannot be satisfied: no variant configured for this key.
return Noop('Variant key {} was not configured in variants {}'.format(
self.variant_key, variants))
variant_value = variant_values[0]
# If the Subject "is a" or "has a" Product, then we're done.
literal_value = self._select_literal(self.subject, variant_value)
if literal_value is not None:
return Return(literal_value)
# Else, attempt to use a configured task to compute the value.
has_waiting_dep = False
dependencies = list(step_context.gen_nodes(self.subject, self.product, variants))
matches = {}
for dep in dependencies:
dep_state = dependency_states.get(dep, None)
if dep_state is None or type(dep_state) == Waiting:
has_waiting_dep = True
continue
elif type(dep_state) == Throw:
return dep_state
elif type(dep_state) == Noop:
continue
elif type(dep_state) != Return:
State.raise_unrecognized(dep_state)
# We computed a value: see whether we can use it.
literal_value = self._select_literal(dep_state.value, variant_value)
if literal_value is not None:
matches[dep] = literal_value
if has_waiting_dep:
return Waiting(dependencies)
elif len(matches) > 1:
# TODO: Multiple successful tasks are not currently supported. We should allow for this
# by adding support for "mergeable" products. see:
# https://github.com/pantsbuild/pants/issues/2526
return Throw(ConflictingProducersError.create(self.subject, self.product, matches))
elif len(matches) == 1:
return Return(matches.values()[0])
return Noop('No source of {}.'.format(self))
def _dependency_nodes(self, step_context, dep_product):
for dependency in getattr(dep_product, self.field or 'dependencies'):
variants = self.variants
if isinstance(dependency, Address):
# If a subject has literal variants for particular dependencies, they win over all else.
dependency, literal_variants = parse_variants(dependency)
variants = Variants.merge(variants, literal_variants)
yield SelectNode(dependency, self.product, variants, None)
def _dependency_nodes(self, step_context, dep_product):
for dependency in getattr(dep_product, self.field or 'dependencies'):
variants = self.variants
if isinstance(dependency, Address):
# If a subject has literal variants for particular dependencies, they win over all else.
dependency, literal_variants = parse_variants(dependency)
variants = Variants.merge(variants, literal_variants)
yield SelectNode(dependency, self.product, variants, None)
def step(self, dependency_states, step_context):
# Request default Variants for the subject, so that if there are any we can propagate
# them to task nodes.
variants = self.variants
variants_node = self._variants_node()
if variants_node:
dep_state = dependency_states.get(variants_node, None)
if dep_state is None or type(dep_state) == Waiting:
return Waiting([variants_node])
elif type(dep_state) == Return:
# A subject's variants are overridden by any dependent's requested variants, so
# we merge them left to right here.
variants = Variants.merge(dep_state.value.default.items(),
variants)
# If there is a variant_key, see whether it has been configured.
variant_value = None
if self.variant_key:
variant_values = [
value for key, value in variants if key == self.variant_key
] if variants else None
if not variant_values:
# Select cannot be satisfied: no variant configured for this key.
return Noop(
'Variant key {} was not configured in variants {}'.format(
self.variant_key, variants))
variant_value = variant_values[0]
# If the Subject "is a" or "has a" Product, then we're done.
literal_value = self._select_literal(self.subject, variant_value)
if literal_value is not None:
return Return(literal_value)
# Else, attempt to use a configured task to compute the value.
has_waiting_dep = False
dependencies = list(
step_context.gen_nodes(self.subject, self.product, variants))
matches = {}
for dep in dependencies:
dep_state = dependency_states.get(dep, None)
if dep_state is None or type(dep_state) == Waiting:
has_waiting_dep = True
continue
elif type(dep_state) == Throw:
return dep_state
elif type(dep_state) == Noop:
continue
elif type(dep_state) != Return:
State.raise_unrecognized(dep_state)
# We computed a value: see whether we can use it.
literal_value = self._select_literal(dep_state.value,
variant_value)
if literal_value is not None:
matches[dep] = literal_value
if has_waiting_dep:
return Waiting(dependencies)
elif len(matches) > 1:
# TODO: Multiple successful tasks are not currently supported. We should allow for this
# by adding support for "mergeable" products. see:
# https://github.com/pantsbuild/pants/issues/2526
return Throw(
ConflictingProducersError.create(self.subject, self.product,
matches))
elif len(matches) == 1:
return Return(matches.values()[0])
return Noop('No source of {}.'.format(self))