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 _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:
tmp_break_indicator = provider.allocateTempVariable(
temp_scope = temp_scope,
name = "break_indicator"
)
statements = [
StatementAssignmentVariable(
variable_ref = ExpressionTargetTempVariableRef(
variable = tmp_break_indicator,
source_ref = source_ref
),
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 = ExpressionAsyncNext(
value = ExpressionTempVariableRef(
variable = tmp_iter_variable,
source_ref = source_ref
),
source_ref = source_ref
)
statements = (
makeTryExceptSingleHandlerNode(
tried = StatementAssignmentVariable(
variable_ref = ExpressionTargetTempVariableRef(
variable = tmp_value_variable,
source_ref = source_ref
),
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_ref = ExpressionTargetTempVariableRef(
variable = tmp_break_indicator,
source_ref = source_ref
),
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 = ExpressionAsyncIter(
value = source,
source_ref = source.getSourceReference()
)
statements += [
# First create the iterator and store it.
StatementAssignmentVariable(
variable_ref = ExpressionTargetTempVariableRef(
variable = tmp_iter_variable,
source_ref = source_ref
),
source = iter_source,
source_ref = source_ref
),
makeTryFinallyStatement(
provider = provider,
tried = StatementLoop(
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 += [
StatementConditional(
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
)
]
statements = (
makeTryFinallyStatement(
provider = provider,
tried = statements,
final = StatementReleaseVariable(
variable = tmp_break_indicator,
source_ref = source_ref
),
source_ref = source_ref
),
)
return makeStatementsSequenceFromStatements(
*statements
)
