def buildAwaitNode(provider, node, source_ref):
return ExpressionYieldFromWaitable(
expression=ExpressionAsyncWait(
expression=buildNode(provider, node.value, source_ref),
source_ref=source_ref,
),
source_ref=source_ref,
)
def _makeIteratorNext(qual, iterator_ref, source_ref):
if getattr(qual, "is_async", 0):
return ExpressionYieldFromWaitable(
expression=ExpressionAsyncNext(value=iterator_ref, source_ref=source_ref),
source_ref=source_ref,
)
else:
return ExpressionBuiltinNext1(value=iterator_ref, source_ref=source_ref)
def _makeIteratorCreation(provider, qual, for_asyncgen, source_ref):
if getattr(qual, "is_async", 0):
result = ExpressionAsyncIter(value=buildNode(provider=provider,
node=qual.iter,
source_ref=source_ref),
source_ref=source_ref)
if not for_asyncgen or python_version < 370:
result = ExpressionYieldFromWaitable(expression=result,
source_ref=source_ref)
return result
else:
return ExpressionBuiltinIter1(value=buildNode(provider=provider,
node=qual.iter,
source_ref=source_ref),
source_ref=source_ref)
def _buildWithNode(provider, context_expr, assign_target, body, sync,
source_ref):
# Many details, pylint: disable=too-many-locals
with_source = buildNode(provider, context_expr, source_ref)
if python_version < 380 and Options.isFullCompat():
source_ref = with_source.getCompatibleSourceReference()
temp_scope = provider.allocateTempScope("with")
tmp_source_variable = provider.allocateTempVariable(temp_scope=temp_scope,
name="source")
tmp_exit_variable = provider.allocateTempVariable(temp_scope=temp_scope,
name="exit")
tmp_enter_variable = provider.allocateTempVariable(temp_scope=temp_scope,
name="enter")
tmp_indicator_variable = provider.allocateTempVariable(
temp_scope=temp_scope, name="indicator")
statements = (
buildAssignmentStatements(
provider=provider,
node=assign_target,
allow_none=True,
source=ExpressionTempVariableRef(variable=tmp_enter_variable,
source_ref=source_ref),
source_ref=source_ref,
),
body,
)
with_body = makeStatementsSequence(statements=statements,
allow_none=True,
source_ref=source_ref)
if body:
deepest = body
while deepest.getVisitableNodes():
deepest = deepest.getVisitableNodes()[-1]
if python_version < 370:
body_lineno = deepest.getCompatibleSourceReference().getLineNumber(
)
else:
body_lineno = deepest.getSourceReference().getLineNumber()
with_exit_source_ref = source_ref.atLineNumber(body_lineno)
else:
with_exit_source_ref = source_ref
# The "__enter__" and "__exit__" were normal attribute lookups under
# CPython2.6, but that changed with CPython2.7.
if python_version < 270:
attribute_lookup_class = ExpressionAttributeLookup
else:
attribute_lookup_class = ExpressionAttributeLookupSpecial
enter_value = ExpressionCallEmpty(
called=attribute_lookup_class(
source=ExpressionTempVariableRef(variable=tmp_source_variable,
source_ref=source_ref),
attribute_name="__enter__" if sync else "__aenter__",
source_ref=source_ref,
),
source_ref=source_ref,
)
exit_value_exception = ExpressionCallNoKeywords(
called=ExpressionTempVariableRef(variable=tmp_exit_variable,
source_ref=with_exit_source_ref),
args=ExpressionMakeTuple(
elements=(
ExpressionCaughtExceptionTypeRef(
source_ref=with_exit_source_ref),
ExpressionCaughtExceptionValueRef(
source_ref=with_exit_source_ref),
ExpressionCaughtExceptionTracebackRef(source_ref=source_ref),
),
source_ref=source_ref,
),
source_ref=with_exit_source_ref,
)
exit_value_no_exception = ExpressionCallNoKeywords(
called=ExpressionTempVariableRef(variable=tmp_exit_variable,
source_ref=source_ref),
args=makeConstantRefNode(constant=(None, None, None),
source_ref=source_ref),
source_ref=with_exit_source_ref,
)
# For "async with", await the entered value and exit value must be awaited.
if not sync:
enter_value = ExpressionYieldFromWaitable(
expression=ExpressionAsyncWaitEnter(expression=enter_value,
source_ref=source_ref),
source_ref=source_ref,
)
exit_value_exception = ExpressionYieldFromWaitable(
expression=ExpressionAsyncWaitExit(expression=exit_value_exception,
source_ref=source_ref),
source_ref=source_ref,
)
exit_value_no_exception = ExpressionYieldFromWaitable(
ExpressionAsyncWaitExit(expression=exit_value_no_exception,
source_ref=source_ref),
source_ref=source_ref,
)
statements = [
# First assign the with context to a temporary variable.
StatementAssignmentVariable(variable=tmp_source_variable,
source=with_source,
source_ref=source_ref)
]
attribute_assignments = [
# Next, assign "__enter__" and "__exit__" attributes to temporary
# variables.
StatementAssignmentVariable(
variable=tmp_exit_variable,
source=attribute_lookup_class(
source=ExpressionTempVariableRef(variable=tmp_source_variable,
source_ref=source_ref),
attribute_name="__exit__" if sync else "__aexit__",
source_ref=source_ref,
),
source_ref=source_ref,
),
StatementAssignmentVariable(variable=tmp_enter_variable,
source=enter_value,
source_ref=source_ref),
]
if python_version >= 360 and sync:
attribute_assignments.reverse()
statements += attribute_assignments
statements.append(
StatementAssignmentVariable(
variable=tmp_indicator_variable,
source=makeConstantRefNode(constant=True, source_ref=source_ref),
source_ref=source_ref,
))
statements += [
makeTryFinallyStatement(
provider=provider,
tried=makeTryExceptSingleHandlerNodeWithPublish(
provider=provider,
tried=with_body,
exception_name="BaseException",
handler_body=StatementsSequence(
statements=(
# Prevents final block from calling __exit__ as
# well.
StatementAssignmentVariable(
variable=tmp_indicator_variable,
source=makeConstantRefNode(constant=False,
source_ref=source_ref),
source_ref=source_ref,
),
makeStatementConditional(
condition=exit_value_exception,
no_branch=makeReraiseExceptionStatement(
source_ref=with_exit_source_ref),
yes_branch=None,
source_ref=with_exit_source_ref,
),
),
source_ref=source_ref,
),
public_exc=python_version >= 270,
source_ref=source_ref,
),
final=makeStatementConditional(
condition=ExpressionComparisonIs(
left=ExpressionTempVariableRef(
variable=tmp_indicator_variable,
source_ref=source_ref),
right=makeConstantRefNode(constant=True,
source_ref=source_ref),
source_ref=source_ref,
),
yes_branch=StatementExpressionOnly(
expression=exit_value_no_exception, source_ref=source_ref),
no_branch=None,
source_ref=source_ref,
),
source_ref=source_ref,
)
]
return makeTryFinallyStatement(
provider=provider,
tried=statements,
final=(
StatementReleaseVariable(variable=tmp_source_variable,
source_ref=with_exit_source_ref),
StatementReleaseVariable(variable=tmp_enter_variable,
source_ref=with_exit_source_ref),
StatementReleaseVariable(variable=tmp_exit_variable,
source_ref=with_exit_source_ref),
StatementReleaseVariable(variable=tmp_indicator_variable,
source_ref=with_exit_source_ref),
),
source_ref=source_ref,
)
def _buildContractionBodyNode(
provider,
node,
emit_class,
start_value,
container_tmp,
iter_tmp,
temp_scope,
assign_provider,
function_body,
for_asyncgen,
source_ref,
):
# This uses lots of variables and branches. There is no good way
# around that, and we deal with many cases, due to having generator
# expressions sharing this code, pylint: disable=too-many-branches,too-many-locals
# Note: The assign_provider is only to cover Python2 list contractions,
# assigning one of the loop variables to the outside scope.
tmp_variables = []
if emit_class is not ExpressionYield:
tmp_variables.append(iter_tmp)
if container_tmp is not None:
tmp_variables.append(container_tmp)
statements = []
# First assign the iterator if we are an outline.
if assign_provider:
statements.append(
StatementAssignmentVariable(
variable=iter_tmp,
source=_makeIteratorCreation(
provider=provider,
qual=node.generators[0],
for_asyncgen=False,
source_ref=source_ref,
),
source_ref=source_ref.atInternal(),
))
if for_asyncgen and python_version >= 370 and node.generators[0].is_async:
statements.append(
StatementAssignmentVariable(
variable=iter_tmp,
source=ExpressionTempVariableRef(variable=iter_tmp,
source_ref=source_ref),
source_ref=source_ref,
))
if start_value is not None:
statements.append(
StatementAssignmentVariable(
variable=container_tmp,
source=makeConstantRefNode(constant=start_value,
source_ref=source_ref),
source_ref=source_ref.atInternal(),
))
if hasattr(node, "elt"):
if start_value is not None:
current_body = emit_class(
ExpressionTempVariableRef(variable=container_tmp,
source_ref=source_ref),
buildNode(
provider=function_body
if not assign_provider else provider,
node=node.elt,
source_ref=source_ref,
),
source_ref=source_ref,
)
else:
assert emit_class is ExpressionYield
current_body = emit_class(
buildNode(provider=function_body,
node=node.elt,
source_ref=source_ref),
source_ref=source_ref,
)
else:
current_body = emit_class(
dict_arg=ExpressionTempVariableRef(variable=container_tmp,
source_ref=source_ref),
key=buildNode(
provider=function_body if not assign_provider else provider,
node=node.key,
source_ref=source_ref,
),
value=buildNode(
provider=function_body if not assign_provider else provider,
node=node.value,
source_ref=source_ref,
),
source_ref=source_ref,
)
if current_body.isExpression():
current_body = StatementExpressionOnly(expression=current_body,
source_ref=source_ref)
for count, qual in enumerate(reversed(node.generators)):
tmp_value_variable = function_body.allocateTempVariable(
temp_scope=temp_scope, name="iter_value_%d" % count)
tmp_variables.append(tmp_value_variable)
# The first iterated value is to be calculated outside of the function
# and will be given as a parameter "_iterated", the others are built
# inside the function.
if qual is node.generators[0]:
iterator_ref = makeVariableRefNode(variable=iter_tmp,
source_ref=source_ref)
if for_asyncgen and python_version >= 370:
iterator_ref = ExpressionYieldFromWaitable(
expression=iterator_ref, source_ref=source_ref)
tmp_iter_variable = None
nested_statements = []
else:
# First create the iterator and store it, next should be loop body
value_iterator = _makeIteratorCreation(
provider=provider if assign_provider else function_body,
qual=qual,
for_asyncgen=False,
source_ref=source_ref,
)
tmp_iter_variable = function_body.allocateTempVariable(
temp_scope=temp_scope, name="contraction_iter_%d" % count)
tmp_variables.append(tmp_iter_variable)
nested_statements = [
StatementAssignmentVariable(
variable=tmp_iter_variable,
source=value_iterator,
source_ref=source_ref,
)
]
iterator_ref = ExpressionTempVariableRef(
variable=tmp_iter_variable, source_ref=source_ref)
loop_statements = [
makeTryExceptSingleHandlerNode(
tried=StatementAssignmentVariable(
variable=tmp_value_variable,
source=_makeIteratorNext(iterator_ref=iterator_ref,
qual=qual,
source_ref=source_ref),
source_ref=source_ref,
),
exception_name=_getStopIterationName(qual),
handler_body=StatementLoopBreak(source_ref=source_ref),
source_ref=source_ref,
),
buildAssignmentStatements(
provider=provider if assign_provider else function_body,
temp_provider=function_body,
node=qual.target,
source=ExpressionTempVariableRef(variable=tmp_value_variable,
source_ref=source_ref),
source_ref=source_ref,
),
]
conditions = buildNodeList(
provider=provider if assign_provider else function_body,
nodes=qual.ifs,
source_ref=source_ref,
)
if len(conditions) >= 1:
loop_statements.append(
makeStatementConditional(
condition=buildAndNode(values=conditions,
source_ref=source_ref),
yes_branch=current_body,
no_branch=None,
source_ref=source_ref,
))
else:
loop_statements.append(current_body)
nested_statements.append(
StatementLoop(
body=StatementsSequence(
statements=mergeStatements(loop_statements),
source_ref=source_ref),
source_ref=source_ref,
))
if tmp_iter_variable is not None:
nested_statements.append(
StatementReleaseVariable(variable=tmp_iter_variable,
source_ref=source_ref))
current_body = StatementsSequence(statements=mergeStatements(
nested_statements, False),
source_ref=source_ref)
statements.append(current_body)
statements = mergeStatements(statements)
release_statements = [
StatementReleaseVariable(variable=tmp_variable, source_ref=source_ref)
for tmp_variable in tmp_variables
]
return statements, release_statements
def _buildForLoopNode(provider, node, sync, source_ref):
# The for loop is re-formulated according to developer manual. An iterator
# is created, and looped until it gives StopIteration. The else block is
# taken if a for loop exits normally, i.e. because of iterator
# exhaustion. We do this by introducing an indicator variable.
# We handle async and sync both here, leading to cases, pylint: disable=too-many-locals
source = buildNode(provider, node.iter, source_ref)
# Temporary variables, we need one for the iterator, and one for the current
# value.
temp_scope = provider.allocateTempScope("for_loop")
tmp_iter_variable = provider.allocateTempVariable(temp_scope=temp_scope,
name="for_iterator")
tmp_value_variable = provider.allocateTempVariable(temp_scope=temp_scope,
name="iter_value")
else_block = buildStatementsNode(
provider=provider,
nodes=node.orelse if node.orelse else None,
source_ref=source_ref,
)
if else_block is not None:
# Indicator variable, will end up with C bool type, and need not be released.
tmp_break_indicator = provider.allocateTempVariable(
temp_scope=temp_scope, name="break_indicator", temp_type="bool")
statements = [
StatementAssignmentVariable(
variable=tmp_break_indicator,
source=makeConstantRefNode(constant=True,
source_ref=source_ref),
source_ref=source_ref,
)
]
else:
statements = []
statements.append(StatementLoopBreak(source_ref=source_ref))
handler_body = makeStatementsSequence(statements=statements,
allow_none=False,
source_ref=source_ref)
if sync:
next_node = ExpressionBuiltinNext1(
value=ExpressionTempVariableRef(variable=tmp_iter_variable,
source_ref=source_ref),
source_ref=source_ref,
)
else:
next_node = ExpressionYieldFromWaitable(
expression=ExpressionAsyncNext(
value=ExpressionTempVariableRef(variable=tmp_iter_variable,
source_ref=source_ref),
source_ref=source_ref,
),
source_ref=source_ref,
)
statements = (
makeTryExceptSingleHandlerNode(
tried=StatementAssignmentVariable(variable=tmp_value_variable,
source=next_node,
source_ref=source_ref),
exception_name="StopIteration" if sync else "StopAsyncIteration",
handler_body=handler_body,
source_ref=source_ref,
),
buildAssignmentStatements(
provider=provider,
node=node.target,
source=ExpressionTempVariableRef(variable=tmp_value_variable,
source_ref=source_ref),
source_ref=source_ref,
),
)
pushBuildContext("loop_body")
statements += (buildStatementsNode(provider=provider,
nodes=node.body,
source_ref=source_ref), )
popBuildContext()
loop_body = makeStatementsSequence(statements=statements,
allow_none=True,
source_ref=source_ref)
cleanup_statements = [
StatementReleaseVariable(variable=tmp_value_variable,
source_ref=source_ref),
StatementReleaseVariable(variable=tmp_iter_variable,
source_ref=source_ref),
]
if else_block is not None:
statements = [
StatementAssignmentVariable(
variable=tmp_break_indicator,
source=makeConstantRefNode(constant=False,
source_ref=source_ref),
source_ref=source_ref,
)
]
else:
statements = []
if sync:
iter_source = ExpressionBuiltinIter1(
value=source, source_ref=source.getSourceReference())
else:
iter_source = ExpressionYieldFromWaitable(
expression=ExpressionAsyncIter(
value=source, source_ref=source.getSourceReference()),
source_ref=source.getSourceReference(),
)
statements += (
# First create the iterator and store it.
StatementAssignmentVariable(variable=tmp_iter_variable,
source=iter_source,
source_ref=source_ref),
makeTryFinallyStatement(
provider=provider,
tried=StatementLoop(loop_body=loop_body, source_ref=source_ref),
final=StatementsSequence(statements=cleanup_statements,
source_ref=source_ref),
source_ref=source_ref,
),
)
if else_block is not None:
statements.append(
makeStatementConditional(
condition=ExpressionComparisonIs(
left=ExpressionTempVariableRef(
variable=tmp_break_indicator, source_ref=source_ref),
right=makeConstantRefNode(constant=True,
source_ref=source_ref),
source_ref=source_ref,
),
yes_branch=else_block,
no_branch=None,
source_ref=source_ref,
))
return makeStatementsSequenceFromStatements(*statements)
def _buildWithNode(provider, context_expr, assign_target, body, sync, source_ref):
# Many details, pylint: disable=too-many-branches,too-many-locals
with_source = buildNode(provider, context_expr, source_ref)
if python_version < 0x380 and Options.is_fullcompat:
source_ref = with_source.getCompatibleSourceReference()
temp_scope = provider.allocateTempScope("with")
tmp_source_variable = provider.allocateTempVariable(
temp_scope=temp_scope, name="source"
)
tmp_exit_variable = provider.allocateTempVariable(
temp_scope=temp_scope, name="exit"
)
tmp_enter_variable = provider.allocateTempVariable(
temp_scope=temp_scope, name="enter"
)
# Indicator variable, will end up with C bool type, and need not be released.
tmp_indicator_variable = provider.allocateTempVariable(
temp_scope=temp_scope, name="indicator", temp_type="bool"
)
statements = (
buildAssignmentStatements(
provider=provider,
node=assign_target,
allow_none=True,
source=ExpressionTempVariableRef(
variable=tmp_enter_variable, source_ref=source_ref
),
source_ref=source_ref,
),
body,
)
with_body = makeStatementsSequence(
statements=statements, allow_none=True, source_ref=source_ref
)
if body and python_version < 0x3A0:
deepest = body
while deepest.getVisitableNodes():
deepest = deepest.getVisitableNodes()[-1]
if python_version < 0x370:
body_lineno = deepest.getCompatibleSourceReference().getLineNumber()
else:
body_lineno = deepest.getSourceReference().getLineNumber()
with_exit_source_ref = source_ref.atLineNumber(body_lineno)
else:
with_exit_source_ref = source_ref
# The "__enter__" and "__exit__" were normal attribute lookups under
# CPython2.6, but that changed with CPython2.7.
if python_version < 0x270:
attribute_lookup_maker = makeExpressionAttributeLookup
else:
attribute_lookup_maker = ExpressionAttributeLookupSpecial
enter_value = ExpressionCallEmpty(
called=attribute_lookup_maker(
expression=ExpressionTempVariableRef(
variable=tmp_source_variable, source_ref=source_ref
),
attribute_name="__enter__" if sync else "__aenter__",
source_ref=source_ref,
),
source_ref=source_ref,
)
exit_value_exception = ExpressionCallNoKeywords(
called=ExpressionTempVariableRef(
variable=tmp_exit_variable, source_ref=with_exit_source_ref
),
args=makeExpressionMakeTuple(
elements=(
ExpressionCaughtExceptionTypeRef(source_ref=with_exit_source_ref),
ExpressionCaughtExceptionValueRef(source_ref=with_exit_source_ref),
ExpressionCaughtExceptionTracebackRef(source_ref=source_ref),
),
source_ref=source_ref,
),
source_ref=with_exit_source_ref,
)
exit_value_no_exception = ExpressionCallNoKeywords(
called=ExpressionTempVariableRef(
variable=tmp_exit_variable, source_ref=source_ref
),
args=makeConstantRefNode(constant=(None, None, None), source_ref=source_ref),
source_ref=with_exit_source_ref,
)
# For "async with", await the entered value and exit value must be awaited.
if not sync:
exit_value_exception = ExpressionYieldFromWaitable(
expression=ExpressionAsyncWaitExit(
expression=exit_value_exception, source_ref=source_ref
),
source_ref=source_ref,
)
exit_value_no_exception = ExpressionYieldFromWaitable(
ExpressionAsyncWaitExit(
expression=exit_value_no_exception, source_ref=source_ref
),
source_ref=source_ref,
)
# First assign the with context to a temporary variable.
statements = [
StatementAssignmentVariable(
variable=tmp_source_variable, source=with_source, source_ref=source_ref
)
]
# Before 3.9, __aenter__ is immediately awaited, after we first do __aexit__ lookup.
if not sync and python_version < 0x390:
enter_value = ExpressionYieldFromWaitable(
expression=ExpressionAsyncWaitEnter(
expression=enter_value, source_ref=source_ref
),
source_ref=source_ref,
)
attribute_enter_assignment = StatementAssignmentVariable(
variable=tmp_enter_variable, source=enter_value, source_ref=source_ref
)
attribute_exit_assignment = StatementAssignmentVariable(
variable=tmp_exit_variable,
source=attribute_lookup_maker(
expression=ExpressionTempVariableRef(
variable=tmp_source_variable, source_ref=source_ref
),
attribute_name="__exit__" if sync else "__aexit__",
source_ref=source_ref,
),
source_ref=source_ref,
)
# Next, assign "__enter__" and "__exit__" attributes to temporary variables, and
# depending on Python versions switch the order of these lookups and the order of
# awaiting enter.
# Normal "with" statements are enter, exit ordered after 3.6, and "async with"
# are since 3.9, and since 3.9 the enter is not awaited, until an exit is present.
if python_version >= 0x390 and not sync:
enter_await_statement = StatementAssignmentVariable(
variable=tmp_enter_variable,
source=ExpressionYieldFromWaitable(
expression=ExpressionAsyncWaitEnter(
expression=ExpressionTempVariableRef(
variable=tmp_enter_variable, source_ref=source_ref
),
source_ref=source_ref,
),
source_ref=source_ref,
),
source_ref=source_ref,
)
attribute_assignments = (
attribute_enter_assignment,
attribute_exit_assignment,
enter_await_statement,
)
elif python_version >= 0x360 and sync:
attribute_assignments = (attribute_enter_assignment, attribute_exit_assignment)
else:
attribute_assignments = (attribute_exit_assignment, attribute_enter_assignment)
statements.extend(attribute_assignments)
statements.append(
StatementAssignmentVariable(
variable=tmp_indicator_variable,
source=makeConstantRefNode(constant=True, source_ref=source_ref),
source_ref=source_ref,
)
)
statements += (
makeTryFinallyStatement(
provider=provider,
tried=makeTryExceptSingleHandlerNodeWithPublish(
provider=provider,
tried=with_body,
exception_name="BaseException",
handler_body=StatementsSequence(
statements=(
# Prevents final block from calling __exit__ as
# well.
StatementAssignmentVariable(
variable=tmp_indicator_variable,
source=makeConstantRefNode(
constant=False, source_ref=source_ref
),
source_ref=source_ref,
),
makeStatementConditional(
condition=exit_value_exception,
no_branch=makeReraiseExceptionStatement(
source_ref=with_exit_source_ref
),
yes_branch=None,
source_ref=with_exit_source_ref,
),
),
source_ref=source_ref,
),
public_exc=python_version >= 0x270,
source_ref=source_ref,
),
final=makeStatementConditional(
condition=ExpressionComparisonIs(
left=ExpressionTempVariableRef(
variable=tmp_indicator_variable, source_ref=source_ref
),
right=makeConstantRefNode(constant=True, source_ref=source_ref),
source_ref=source_ref,
),
yes_branch=StatementExpressionOnly(
expression=exit_value_no_exception, source_ref=source_ref
),
no_branch=None,
source_ref=source_ref,
),
source_ref=source_ref,
),
)
return makeTryFinallyStatement(
provider=provider,
tried=statements,
final=(
StatementReleaseVariable(
variable=tmp_source_variable, source_ref=with_exit_source_ref
),
StatementReleaseVariable(
variable=tmp_enter_variable, source_ref=with_exit_source_ref
),
StatementReleaseVariable(
variable=tmp_exit_variable, source_ref=with_exit_source_ref
),
),
source_ref=source_ref,
)
