def buildImportModulesNode(provider, node, source_ref):
# Import modules statement. As described in the Developer Manual, these
# statements can be treated as several ones.
import_names = [(import_desc.name, import_desc.asname)
for import_desc in node.names]
import_nodes = []
for import_desc in import_names:
module_name, local_name = import_desc
module_topname = module_name.split(".")[0]
# Note: The "level" of import is influenced by the future absolute
# imports.
level = (makeConstantRefNode(0, source_ref, True)
if _future_specs[-1].isAbsoluteImport() else None)
import_node = ExpressionBuiltinImport(
name=makeConstantRefNode(module_name, source_ref, True),
globals_arg=ExpressionBuiltinGlobals(source_ref),
locals_arg=makeConstantRefNode(None, source_ref, True),
fromlist=makeConstantRefNode(None, source_ref, True),
level=level,
source_ref=source_ref,
)
if local_name:
# If is gets a local name, the real name must be used as a
# temporary value only, being looked up recursively.
for import_name in module_name.split(".")[1:]:
import_node = ExpressionImportName(
module=import_node,
import_name=import_name,
# TODO: Does level make sense at all, should be removed.
level=0,
source_ref=source_ref,
)
# If a name was given, use the one provided, otherwise the import gives
# the top level package name given for assignment of the imported
# module.
import_nodes.append(
StatementAssignmentVariableName(
provider=provider,
variable_name=mangleName(
local_name if local_name is not None else module_topname,
provider),
source=import_node,
source_ref=source_ref,
))
# Note: Each import is sequential. It will potentially succeed, and the
# failure of a later one is not changing that one bit . We can therefore
# have a sequence of imports that only import one thing therefore.
return makeStatementsSequenceOrStatement(statements=import_nodes,
source_ref=source_ref)
def makeAbsoluteImportNode(module_name, source_ref):
return ExpressionBuiltinImport(
name=makeConstantRefNode(module_name, source_ref, True),
globals_arg=None,
locals_arg=None,
fromlist=None,
level=makeConstantRefNode(0, source_ref, True),
source_ref=source_ref)
def buildImportFromNode(provider, node, source_ref):
# "from .. import .." statements. This may trigger a star import, or
# multiple names being looked up from the given module variable name.
# This is pretty complex.
# pylint: disable=too-many-branches,too-many-locals,too-many-statements
module_name = node.module if node.module is not None else ""
level = node.level
# Use default level under some circumstances.
if level == -1:
level = None
elif level == 0 and not _future_specs[-1].isAbsoluteImport():
level = None
if level is not None:
level_obj = makeConstantRefNode(level, source_ref, True)
else:
level_obj = None
# Importing from "__future__" module may enable flags to the parser,
# that we need to know about, handle that.
if module_name == "__future__":
_handleFutureImport(provider, node, source_ref)
target_names = []
import_names = []
# Mapping imported "fromlist" to assigned "fromlist" if any, handling the
# star case as well.
for import_desc in node.names:
object_name, local_name = import_desc.name, import_desc.asname
if object_name == "*":
target_names.append(None)
assert local_name is None
else:
target_names.append(
local_name if local_name is not None else object_name)
import_names.append(object_name)
# Star imports get special treatment.
if None in target_names:
# More than "*" is a syntax error in Python, need not care about this at
# all, it's only allowed value for import list in this case.
assert target_names == [None]
# Python3 made it so that these can only occur on the module level,
# so this a syntax error if not there. For Python2 it is OK to
# occur everywhere though.
if not provider.isCompiledPythonModule() and python_version >= 0x300:
raiseSyntaxError(
"import * only allowed at module level",
source_ref.atColumnNumber(node.col_offset),
)
if provider.isCompiledPythonModule():
import_globals = ExpressionBuiltinGlobals(source_ref)
import_locals = ExpressionBuiltinGlobals(source_ref)
else:
import_globals = ExpressionBuiltinGlobals(source_ref)
import_locals = makeConstantRefNode({}, source_ref, True)
return StatementImportStar(
target_scope=provider.getLocalsScope(),
module_import=ExpressionBuiltinImport(
name=makeConstantRefNode(module_name, source_ref, True),
globals_arg=import_globals,
locals_arg=import_locals,
fromlist=makeConstantRefNode(("*", ), source_ref, True),
level=level_obj,
source_ref=source_ref,
),
source_ref=source_ref,
)
else:
if module_name == "__future__":
imported_from_module = ExpressionImportModuleHard(
module_name="__future__", source_ref=source_ref)
else:
imported_from_module = ExpressionBuiltinImport(
name=makeConstantRefNode(module_name, source_ref, True),
globals_arg=ExpressionBuiltinGlobals(source_ref),
locals_arg=makeConstantRefNode(None, source_ref, True),
fromlist=makeConstantRefNode(tuple(import_names), source_ref,
True),
level=level_obj,
source_ref=source_ref,
)
# If we have multiple names to import, consider each.
multi_names = len(target_names) > 1
statements = []
if multi_names:
tmp_import_from = provider.allocateTempVariable(
temp_scope=provider.allocateTempScope("import_from"),
name="module")
statements.append(
StatementAssignmentVariable(
variable=tmp_import_from,
source=imported_from_module,
source_ref=source_ref,
))
imported_from_module = ExpressionTempVariableRef(
variable=tmp_import_from, source_ref=source_ref)
import_statements = []
first = True
for target_name, import_name in zip(target_names, import_names):
# Make a clone of the variable reference, if we are going to use
# another one.
if not first:
imported_from_module = imported_from_module.makeClone()
first = False
import_statements.append(
StatementAssignmentVariableName(
provider=provider,
variable_name=mangleName(target_name, provider),
source=ExpressionImportName(
module=imported_from_module,
import_name=import_name,
level=0,
source_ref=source_ref,
),
source_ref=source_ref,
))
# Release the temporary module value as well.
if multi_names:
statements.append(
makeTryFinallyStatement(
provider=provider,
tried=import_statements,
final=(StatementReleaseVariable(variable=tmp_import_from,
source_ref=source_ref), ),
source_ref=source_ref,
))
else:
statements.extend(import_statements)
# Note: Each import is sequential. It can succeed, and the failure of a
# later one is not undoing previous ones. We can therefore have a
# sequence of imports that each only import one thing therefore.
return StatementsSequence(statements=mergeStatements(statements),
source_ref=source_ref)