cadquery-freecad-module/CadQuery/Libs/jedi/evaluate/recursion.py
2015-10-26 16:25:38 -04:00

158 lines
5.0 KiB
Python

"""
Recursions are the recipe of |jedi| to conquer Python code. However, someone
must stop recursions going mad. Some settings are here to make |jedi| stop at
the right time. You can read more about them :ref:`here <settings-recursion>`.
Next to :mod:`jedi.evaluate.cache` this module also makes |jedi| not
thread-safe. Why? ``execution_recursion_decorator`` uses class variables to
count the function calls.
"""
from jedi import debug
from jedi import settings
from jedi.evaluate import compiled
from jedi.evaluate import iterable
def recursion_decorator(func):
def run(evaluator, stmt, *args, **kwargs):
rec_detect = evaluator.recursion_detector
# print stmt, len(self.node_statements())
if rec_detect.push_stmt(stmt):
return []
else:
result = func(evaluator, stmt, *args, **kwargs)
rec_detect.pop_stmt()
return result
return run
class RecursionDetector(object):
"""
A decorator to detect recursions in statements. In a recursion a statement
at the same place, in the same module may not be executed two times.
"""
def __init__(self):
self.top = None
self.current = None
def push_stmt(self, stmt):
self.current = _RecursionNode(stmt, self.current)
check = self._check_recursion()
if check:
debug.warning('catched stmt recursion: %s against %s @%s', stmt,
check.stmt, stmt.start_pos)
self.pop_stmt()
return True
return False
def pop_stmt(self):
if self.current is not None:
# I don't know how current can be None, but sometimes it happens
# with Python3.
self.current = self.current.parent
def _check_recursion(self):
test = self.current
while True:
test = test.parent
if self.current == test:
return test
if not test:
return False
def node_statements(self):
result = []
n = self.current
while n:
result.insert(0, n.stmt)
n = n.parent
return result
class _RecursionNode(object):
""" A node of the RecursionDecorator. """
def __init__(self, stmt, parent):
self.script = stmt.get_parent_until()
self.position = stmt.start_pos
self.parent = parent
self.stmt = stmt
# Don't check param instances, they are not causing recursions
# The same's true for the builtins, because the builtins are really
# simple.
self.is_ignored = self.script == compiled.builtin
def __eq__(self, other):
if not other:
return None
return self.script == other.script \
and self.position == other.position \
and not self.is_ignored and not other.is_ignored
def execution_recursion_decorator(func):
def run(execution, **kwargs):
detector = execution._evaluator.execution_recursion_detector
if detector.push_execution(execution):
result = []
else:
result = func(execution, **kwargs)
detector.pop_execution()
return result
return run
class ExecutionRecursionDetector(object):
"""
Catches recursions of executions.
It is designed like a Singelton. Only one instance should exist.
"""
def __init__(self):
self.recursion_level = 0
self.parent_execution_funcs = []
self.execution_funcs = set()
self.execution_count = 0
def __call__(self, execution):
debug.dbg('Execution recursions: %s', execution, self.recursion_level,
self.execution_count, len(self.execution_funcs))
if self.check_recursion(execution):
result = []
else:
result = self.func(execution)
self.pop_execution()
return result
def pop_execution(cls):
cls.parent_execution_funcs.pop()
cls.recursion_level -= 1
def push_execution(cls, execution):
in_par_execution_funcs = execution.base in cls.parent_execution_funcs
in_execution_funcs = execution.base in cls.execution_funcs
cls.recursion_level += 1
cls.execution_count += 1
cls.execution_funcs.add(execution.base)
cls.parent_execution_funcs.append(execution.base)
if cls.execution_count > settings.max_executions:
return True
if isinstance(execution.base, (iterable.Array, iterable.Generator)):
return False
module = execution.get_parent_until()
if module == compiled.builtin:
return False
if in_par_execution_funcs:
if cls.recursion_level > settings.max_function_recursion_level:
return True
if in_execution_funcs and \
len(cls.execution_funcs) > settings.max_until_execution_unique:
return True
if cls.execution_count > settings.max_executions_without_builtins:
return True
return False