hub/venv/lib/python3.7/site-packages/jedi/inference/dynamic_params.py

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"""
One of the really important features of |jedi| is to have an option to
understand code like this::
def foo(bar):
bar. # completion here
foo(1)
There's no doubt wheter bar is an ``int`` or not, but if there's also a call
like ``foo('str')``, what would happen? Well, we'll just show both. Because
that's what a human would expect.
It works as follows:
- |Jedi| sees a param
- search for function calls named ``foo``
- execute these calls and check the input.
"""
from jedi import settings
from jedi import debug
from jedi.parser_utils import get_parent_scope
from jedi.inference.cache import inference_state_method_cache
from jedi.inference.arguments import TreeArguments
from jedi.inference.param import get_executed_param_names
from jedi.inference.helpers import is_stdlib_path
from jedi.inference.utils import to_list
from jedi.inference.value import instance
from jedi.inference.base_value import ValueSet, NO_VALUES
from jedi.inference.references import get_module_contexts_containing_name
from jedi.inference import recursion
MAX_PARAM_SEARCHES = 20
def _avoid_recursions(func):
def wrapper(function_value, param_index):
inf = function_value.inference_state
with recursion.execution_allowed(inf, function_value.tree_node) as allowed:
# We need to catch recursions that may occur, because an
# anonymous functions can create an anonymous parameter that is
# more or less self referencing.
if allowed:
inf.dynamic_params_depth += 1
try:
return func(function_value, param_index)
finally:
inf.dynamic_params_depth -= 1
return NO_VALUES
return wrapper
@debug.increase_indent
@_avoid_recursions
def dynamic_param_lookup(function_value, param_index):
"""
A dynamic search for param values. If you try to complete a type:
>>> def func(foo):
... foo
>>> func(1)
>>> func("")
It is not known what the type ``foo`` without analysing the whole code. You
have to look for all calls to ``func`` to find out what ``foo`` possibly
is.
"""
funcdef = function_value.tree_node
if not settings.dynamic_params:
return NO_VALUES
path = function_value.get_root_context().py__file__()
if path is not None and is_stdlib_path(path):
# We don't want to search for references in the stdlib. Usually people
# don't work with it (except if you are a core maintainer, sorry).
# This makes everything slower. Just disable it and run the tests,
# you will see the slowdown, especially in 3.6.
return NO_VALUES
if funcdef.type == 'lambdef':
string_name = _get_lambda_name(funcdef)
if string_name is None:
return NO_VALUES
else:
string_name = funcdef.name.value
debug.dbg('Dynamic param search in %s.', string_name, color='MAGENTA')
module_context = function_value.get_root_context()
arguments_list = _search_function_arguments(module_context, funcdef, string_name)
values = ValueSet.from_sets(
get_executed_param_names(
function_value, arguments
)[param_index].infer()
for arguments in arguments_list
)
debug.dbg('Dynamic param result finished', color='MAGENTA')
return values
@inference_state_method_cache(default=None)
@to_list
def _search_function_arguments(module_context, funcdef, string_name):
"""
Returns a list of param names.
"""
compare_node = funcdef
if string_name == '__init__':
cls = get_parent_scope(funcdef)
if cls.type == 'classdef':
string_name = cls.name.value
compare_node = cls
found_arguments = False
i = 0
inference_state = module_context.inference_state
if settings.dynamic_params_for_other_modules:
module_contexts = get_module_contexts_containing_name(
inference_state, [module_context], string_name,
# Limit the amounts of files to be opened massively.
limit_reduction=5,
)
else:
module_contexts = [module_context]
for for_mod_context in module_contexts:
for name, trailer in _get_potential_nodes(for_mod_context, string_name):
i += 1
# This is a simple way to stop Jedi's dynamic param recursion
# from going wild: The deeper Jedi's in the recursion, the less
# code should be inferred.
if i * inference_state.dynamic_params_depth > MAX_PARAM_SEARCHES:
return
random_context = for_mod_context.create_context(name)
for arguments in _check_name_for_execution(
inference_state, random_context, compare_node, name, trailer):
found_arguments = True
yield arguments
# If there are results after processing a module, we're probably
# good to process. This is a speed optimization.
if found_arguments:
return
def _get_lambda_name(node):
stmt = node.parent
if stmt.type == 'expr_stmt':
first_operator = next(stmt.yield_operators(), None)
if first_operator == '=':
first = stmt.children[0]
if first.type == 'name':
return first.value
return None
def _get_potential_nodes(module_value, func_string_name):
try:
names = module_value.tree_node.get_used_names()[func_string_name]
except KeyError:
return
for name in names:
bracket = name.get_next_leaf()
trailer = bracket.parent
if trailer.type == 'trailer' and bracket == '(':
yield name, trailer
def _check_name_for_execution(inference_state, context, compare_node, name, trailer):
from jedi.inference.value.function import BaseFunctionExecutionContext
def create_args(value):
arglist = trailer.children[1]
if arglist == ')':
arglist = None
args = TreeArguments(inference_state, context, arglist, trailer)
from jedi.inference.value.instance import InstanceArguments
if value.tree_node.type == 'classdef':
created_instance = instance.TreeInstance(
inference_state,
value.parent_context,
value,
args
)
return InstanceArguments(created_instance, args)
else:
if value.is_bound_method():
args = InstanceArguments(value.instance, args)
return args
for value in inference_state.infer(context, name):
value_node = value.tree_node
if compare_node == value_node:
yield create_args(value)
elif isinstance(value.parent_context, BaseFunctionExecutionContext) \
and compare_node.type == 'funcdef':
# Here we're trying to find decorators by checking the first
# parameter. It's not very generic though. Should find a better
# solution that also applies to nested decorators.
param_names = value.parent_context.get_param_names()
if len(param_names) != 1:
continue
values = param_names[0].infer()
if [v.tree_node for v in values] == [compare_node]:
# Found a decorator.
module_context = context.get_root_context()
execution_context = value.as_context(create_args(value))
potential_nodes = _get_potential_nodes(module_context, param_names[0].string_name)
for name, trailer in potential_nodes:
if value_node.start_pos < name.start_pos < value_node.end_pos:
random_context = execution_context.create_context(name)
iterator = _check_name_for_execution(
inference_state,
random_context,
compare_node,
name,
trailer
)
for arguments in iterator:
yield arguments