Source code for polygraphy.func.func

# Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# See the License for the specific language governing permissions and
# limitations under the License.
import copy
import functools
import inspect

from polygraphy import config, mod
from polygraphy.logger import G_LOGGER

def make_iterable(obj):
    return obj if type(obj) == tuple else (obj,)

[docs]@mod.export() def extend(extend_func): """ A decorator that uses the function it decorates to extend the function provided as a parameter. This is best illustrated with an example: :: def x(a0, a1, a2): rv0 = [a0, a1, a2] rv1 = None return rv0, rv1 @extend(x) def y(rv0, rv1): rv0.append(-1) # We can now call `y` as if it were `x`, and we will receive # the return values from `x` after any modifications by `y` rv0, rv1 = y(1, 2, 3) assert rv0 == [1, 2, 3, -1] assert rv1 is None In this case, ``extend`` is essentially syntactic sugar for: :: def y(a0, a1, a2): rv0, rv1 = x(a0, a1, a2) # Body of `y` from previous section rv0.append(-1) return rv0, rv1 If ``y`` does not return anything, or returns ``None``, then ``extend`` will ensure that the return value of ``x`` is forwarded to the caller. This means that ``y`` will provide exactly the same interface as ``x``. If `y` returns something other than ``None``, then its return value will be provided to the caller, and the return value of ``x`` will be discarded. NOTE: This function will automatically unpack tuples returned by the function being extended. Thus, the following implementation of ``x`` would behave just like the one mentioned above: :: def x(a0, a1, a2): ret = (rv0, rv1) return ret # Tuple will be unpacked, and `y` still sees 2 parameters Args: extend_func (Callable): A callable to extend. """ def extend_decorator(func): @functools.wraps(func) def extended_func(*args, **kwargs): extend_func_retval = extend_func(*args, **kwargs) extend_func_ret_tuple = make_iterable(extend_func_retval) func_args = inspect.signature(func).parameters # Special case for when the extended function does not return anything if len(func_args) == 0 and len(extend_func_ret_tuple) == 1 and extend_func_ret_tuple[0] is None: func_retval = func() elif len(extend_func_ret_tuple) == len(func_args): func_retval = func(*extend_func_ret_tuple) else: def try_get_name(fn): try: return fn.__name__ except: return fn G_LOGGER.critical( "Function: {:} accepts {:} parameter(s), but " "needs to accept {:} parameter(s) from: {:} instead.\nNote: Parameters should be: {:}".format( try_get_name(func), len(func_args), len(extend_func_ret_tuple), try_get_name(extend_func), tuple(map(type, extend_func_ret_tuple)), ) ) if func_retval is not None: return func_retval return extend_func_retval return extended_func return extend_decorator
@mod.export() def constantmethod(func): """ A decorator that denotes constant methods. NOTE: This decorator does nothing if the POLYGRAPHY_INTERNAL_CORRECTNESS_CHECKS environment variable is not set to `1` Example: :: class Dummy(object): def __init__(self): self.x = 1 @func.constantmethod def modify_x(self): self.x = 2 d = Dummy() d.modify_x() # This will fail! This provides only minimal protection against accidental mutation of instance attributes. For example, if a class includes references (e.g. a numpy array member), this function cannot ensure that the contents of that member (e.g. the values in a numpy array) will remain unchanged. """ if not config.INTERNAL_CORRECTNESS_CHECKS: return func @functools.wraps(func) def wrapper(self, *args, **kwargs): old_dict = copy.copy(vars(self)) ret = None try: ret = func(self, *args, **kwargs) finally: if vars(self) != old_dict: G_LOGGER.internal_error( "{:} was mutated in a constant method! Note:\nOld state: {:}\nNew state: {:}".format( self, old_dict, vars(self) ) ) return ret return wrapper