Fix pyre errors in NoiseTunnel (#1402)

Summary:

Initial work on fixing Pyre errors in Noise Tunnel

Reviewed By: craymichael

Differential Revision: D64677341

Author: Vivek Miglani

captum/attr/_core/noise_tunnel.py

@@ -2,7 +2,7 @@
 
 # pyre-strict
 from enum import Enum
-from typing import Any, Callable, cast, Dict, List, Optional, Tuple, Union
+from typing import Any, Callable, cast, Dict, List, Optional, Sequence, Tuple, Union
 
 import torch
 from captum._utils.common import (
@@ -27,8 +27,7 @@ class NoiseTunnelType(Enum):
     vargrad = 3
 
 
-# pyre-fixme[5]: Global expression must be annotated.
-SUPPORTED_NOISE_TUNNEL_TYPES = list(NoiseTunnelType.__members__.keys())
+SUPPORTED_NOISE_TUNNEL_TYPES: List[str] = list(NoiseTunnelType.__members__.keys())
 
 
 class NoiseTunnel(Attribution):
@@ -58,6 +57,10 @@ class NoiseTunnel(Attribution):
     It is assumed that the batch size is the first dimension of input tensors.
     """
 
+    is_delta_supported: bool
+    _multiply_by_inputs: bool
+    is_gradient_method: bool
+
     def __init__(self, attribution_method: Attribution) -> None:
         r"""
         Args:
@@ -66,19 +69,15 @@ def __init__(self, attribution_method: Attribution) -> None:
                         Conductance or Saliency.
         """
         self.attribution_method = attribution_method
-        # pyre-fixme[4]: Attribute must be annotated.
         self.is_delta_supported = self.attribution_method.has_convergence_delta()
-        # pyre-fixme[4]: Attribute must be annotated.
         self._multiply_by_inputs = self.attribution_method.multiplies_by_inputs
-        # pyre-fixme[4]: Attribute must be annotated.
         self.is_gradient_method = isinstance(
             self.attribution_method, GradientAttribution
         )
         Attribution.__init__(self, self.attribution_method.forward_func)
 
     @property
-    # pyre-fixme[3]: Return type must be annotated.
-    def multiplies_by_inputs(self):
+    def multiplies_by_inputs(self) -> bool:
         return self._multiply_by_inputs
 
     @log_usage()
@@ -205,9 +204,10 @@ def attribute(
                 nt_samples_batch_size, kwargs_copy, inputs, draw_baseline_from_distrib
             )
 
-            sum_attributions: List[Union[None, Tensor]] = []
-            sum_attributions_sq: List[Union[None, Tensor]] = []
+            sum_attributions: Sequence[Union[None, Tensor]] = []
+            sum_attributions_sq: Sequence[Union[None, Tensor]] = []
             delta_partial_list: List[Tensor] = []
+            is_attrib_tuple = is_inputs_tuple
 
             for _ in range(nt_samples_partition):
                 inputs_with_noise = self._add_noise_to_inputs(
@@ -225,11 +225,7 @@ def attribute(
                 )
 
                 if len(sum_attributions) == 0:
-                    # pyre-fixme[9]: sum_attributions has type
-                    #  `List[Optional[Tensor]]`; used as `List[None]`.
                     sum_attributions = [None] * len(attributions_partial)
-                    # pyre-fixme[9]: sum_attributions_sq has type
-                    #  `List[Optional[Tensor]]`; used as `List[None]`.
                     sum_attributions_sq = [None] * len(attributions_partial)
 
                 self._update_partial_attribution_and_delta(
@@ -297,7 +293,6 @@ def attribute(
 
         return self._apply_checks_and_return_attributions(
             attributions,
-            # pyre-fixme[61]: `is_attrib_tuple` is undefined, or not always defined.
             is_attrib_tuple,
             return_convergence_delta,
             delta,
@@ -348,9 +343,7 @@ def _add_noise_to_input(
         bsz = input.shape[0]
 
         # expand input size by the number of drawn samples
-        # pyre-fixme[58]: `+` is not supported for operand types `Tuple[int]`
-        #  and `Size`.
-        input_expanded_size = (bsz * nt_samples_partition,) + input.shape[1:]
+        input_expanded_size = (bsz * nt_samples_partition,) + tuple(input.shape[1:])
 
         # expand stdev for the shape of the input and number of drawn samples
         stdev_expanded = torch.tensor(stdev, device=input.device).repeat(
@@ -375,14 +368,13 @@ def _update_sum_attribution_and_sq(
         bsz = attribution.shape[0] // nt_samples_batch_size_inter
         attribution_shape = cast(Tuple[int, ...], (bsz, nt_samples_batch_size_inter))
         if len(attribution.shape) > 1:
-            # pyre-fixme[22]: The cast is redundant.
-            attribution_shape += cast(Tuple[int, ...], tuple(attribution.shape[1:]))
+            attribution_shape += tuple(attribution.shape[1:])
 
         attribution = attribution.view(attribution_shape)
         current_attribution_sum = attribution.sum(dim=1, keepdim=False)
-        # pyre-fixme[58]: `**` is not supported for operand types `Tensor` and
-        #  `int`.
-        current_attribution_sq = torch.sum(attribution**2, dim=1, keepdim=False)
+        current_attribution_sq = torch.sum(
+            torch.pow(attribution, 2), dim=1, keepdim=False
+        )
 
         sum_attribution[i] = (
             current_attribution_sum
@@ -398,8 +390,7 @@ def _update_sum_attribution_and_sq(
     def _compute_partial_attribution(
         self,
         inputs_with_noise_partition: Tuple[Tensor, ...],
-        # pyre-fixme[2]: Parameter annotation cannot be `Any`.
-        kwargs_partition: Any,
+        kwargs_partition: object,
         is_inputs_tuple: bool,
         return_convergence_delta: bool,
     ) -> Tuple[Tuple[Tensor, ...], bool, Union[None, Tensor]]:
@@ -505,14 +496,12 @@ def _apply_checks_and_return_attributions(
     ) -> Union[
         TensorOrTupleOfTensorsGeneric, Tuple[TensorOrTupleOfTensorsGeneric, Tensor]
     ]:
-        # pyre-fixme[9]: Unable to unpack `Union[Tensor, typing.Tuple[Tensor,
-        #  ...]]`, expected a tuple.
-        attributions = _format_output(is_attrib_tuple, attributions)
+        attributions_tuple = _format_output(is_attrib_tuple, attributions)
 
         ret = (
-            (attributions, cast(Tensor, delta))
+            (attributions_tuple, cast(Tensor, delta))
             if self.is_delta_supported and return_convergence_delta
-            else attributions
+            else attributions_tuple
         )
         ret = cast(
             # pyre-fixme[34]: `Variable[TensorOrTupleOfTensorsGeneric <: