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mirror of https://github.com/QData/TextAttack.git synced 2021-10-13 00:05:06 +03:00

textfooler recipe working

This commit is contained in:
uvafan
2020-05-17 18:23:07 -04:00
parent 5c0584acd7
commit b94684971e
22 changed files with 140 additions and 89 deletions

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@@ -10,7 +10,7 @@
"""
from textattack.shared.attack import Attack
from textattack.constraints.overlap import WordsPerturbed
from textattack.constraints.overlap import MaxWordsPerturbed
from textattack.constraints.grammaticality.language_models import Google1BillionWordsLanguageModel
from textattack.constraints.semantics import WordEmbeddingDistance, RepeatModification, StopwordModification
from textattack.goal_functions import UntargetedClassification
@@ -26,12 +26,18 @@ def Alzantot2018(model):
# "[We] fix the hyperparameter values to S = 60, N = 8, K = 4, and δ = 0.5"
#
transformation = WordSwapEmbedding(max_candidates=8)
constraints = []
#
# Don't modify the same word twice or stopwords
#
constraints = [
RepeatModification(),
StopwordModification()
]
#
# Maximum words perturbed percentage of 20%
#
constraints.append(
WordsPerturbed(max_percent=0.2)
MaxWordsPerturbed(max_percent=0.2)
)
#
# Maximum word embedding euclidean distance of 0.5.
@@ -52,7 +58,6 @@ def Alzantot2018(model):
#
# Perform word substitution with a genetic algorithm.
#
attack = GeneticAlgorithm(goal_function, constraints=constraints,
transformation=transformation, pop_size=60, max_iters=20)
return attack
search_method = GeneticAlgorithm(pop_size=60, max_iters=20)
return Attack(goal_function, constraint, transformation, search_method)

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@@ -9,8 +9,9 @@
ArXiv, abs/1801.00554.
"""
from textattack.shared.attack import Attack
from textattack.constraints.grammaticality import PartOfSpeech, LanguageTool
from textattack.constraints.semantics import WordEmbeddingDistance
from textattack.constraints.semantics import WordEmbeddingDistance, RepeatModification, StopwordModification
from textattack.constraints.semantics.sentence_encoders import UniversalSentenceEncoder, BERT
from textattack.goal_functions import UntargetedClassification
from textattack.search_methods import GeneticAlgorithm
@@ -24,7 +25,14 @@ def Alzantot2018Adjusted(model, SE_thresh=0.98, sentence_encoder='bert'):
#
# "[We] fix the hyperparameter values to S = 60, N = 8, K = 4, and δ = 0.5"
#
transformation = WordSwapEmbedding(max_candidates=50, textfooler_stopwords=True)
transformation = WordSwapEmbedding(max_candidates=50)
#
# Don't modify the same word twice or stopwords
#
constraints = [
RepeatModification(),
StopwordModification()
]
#
# Minimum word embedding cosine similarity of 0.9.
#
@@ -55,8 +63,8 @@ def Alzantot2018Adjusted(model, SE_thresh=0.98, sentence_encoder='bert'):
#
goal_function = UntargetedClassification(model)
#
# Greedily swap words with "Word Importance Ranking".
# Perform word substitution with a genetic algorithm.
#
attack = GeneticAlgorithm(goal_function, transformation=transformation,
constraints=constraints, pop_size=60, max_iters=20)
return attack
search_method = GeneticAlgorithm(pop_size=60, max_iters=20)
return Attack(goal_function, constraint, transformation, search_method)

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@@ -8,6 +8,8 @@
"""
from textattack.shared.attack import Attack
from textattack.constraints.semantics import RepeatModification, StopwordModification
from textattack.constraints.overlap import LevenshteinEditDistance
from textattack.goal_functions import UntargetedClassification
from textattack.search_methods import GreedyWordSwapWIR
@@ -39,12 +41,19 @@ def DeepWordBugGao2018(model, use_all_transformations=True):
# (ϵ = 30).
transformation = WordSwapRandomCharacterSubstitution()
#
# Don't modify the same word twice or stopwords
#
constraints = [
RepeatModification(),
StopwordModification()
]
#
# In these experiments, we hold the maximum difference
# on edit distance (ϵ) to a constant 30 for each sample.
#
constraints = [
constraints.append(
LevenshteinEditDistance(30)
]
)
#
# Goal is untargeted classification
#
@@ -52,7 +61,6 @@ def DeepWordBugGao2018(model, use_all_transformations=True):
#
# Greedily swap words with "Word Importance Ranking".
#
attack = GreedyWordSwapWIR(goal_function, transformation=transformation,
constraints=constraints, max_depth=None)
search_method = GreedyWordSwapWIR()
return attack
return Attack(goal_function, constraints, transformation, search_method)

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@@ -11,10 +11,11 @@
paper).
"""
from textattack.shared.attack import Attack
from textattack.goal_functions import UntargetedClassification
from textattack.constraints.grammaticality import PartOfSpeech
from textattack.constraints.overlap import WordsPerturbed
from textattack.constraints.semantics import WordEmbeddingDistance
from textattack.constraints.overlap import MaxWordsPerturbed
from textattack.constraints.semantics import WordEmbeddingDistance, RepeatModification, StopwordModification
from textattack.search_methods import BeamSearch
from textattack.transformations import WordSwapGradientBased
@@ -23,14 +24,20 @@ def HotFlipEbrahimi2017(model):
# "HotFlip ... uses the gradient with respect to a one-hot input
# representation to efficiently estimate which individual change has the
# highest estimated loss."
transformation = WordSwapGradientBased(model, top_n=1, replace_stopwords=False)
constraints = []
transformation = WordSwapGradientBased(model, top_n=1)
#
# Don't modify the same word twice or stopwords
#
constraints = [
RepeatModification(),
StopwordModification()
]
#
# 0. "We were able to create only 41 examples (2% of the correctly-
# classified instances of the SST test set) with one or two flips."
#
constraints.append(
WordsPerturbed(max_num_words=2)
MaxWordsPerturbed(max_num_words=2)
)
#
# 1. "The cosine similarity between the embedding of words is bigger than a
@@ -52,7 +59,6 @@ def HotFlipEbrahimi2017(model):
# well together to confuse a classifier ... The adversary uses a beam size
# of 10."
#
attack = BeamSearch(goal_function, constraints=constraints,
transformation=transformation, beam_width=10)
return attack
search_method = BeamSearch(beam_width=10)
return Attack(goal_function, constraints, transformation, search_method)

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@@ -7,11 +7,13 @@
https://openreview.net/pdf?id=r1QZ3zbAZ.
"""
from textattack.constraints.overlap import WordsPerturbed
from textattack.shared.attack import Attack
from textattack.constraints.overlap import MaxWordsPerturbed
from textattack.constraints.grammaticality.language_models import GPT2
from textattack.constraints.semantics.sentence_encoders import ThoughtVector
from textattack.constraints.semantics import RepeatModification, StopwordModification
from textattack.goal_functions import UntargetedClassification
from textattack.search_methods import GreedyWordSwap
from textattack.search_methods import GreedySearch
from textattack.transformations import WordSwapEmbedding
def Kuleshov2017(model):
@@ -25,11 +27,17 @@ def Kuleshov2017(model):
#
transformation = WordSwapEmbedding(max_candidates=15)
#
# Don't modify the same word twice or stopwords
#
constraints = [
RepeatModification(),
StopwordModification()
]
#
# Maximum of 50% of words perturbed (δ in the paper).
#
constraints = []
constraints.append(
WordsPerturbed(max_percent=0.5)
MaxWordsPerturbed(max_percent=0.5)
)
#
# Maximum thought vector Euclidean distance of λ_1 = 0.2. (eq. 4)
@@ -52,10 +60,6 @@ def Kuleshov2017(model):
#
# Perform word substitution with a genetic algorithm.
#
attack = GreedyWordSwap(goal_function, constraints=constraints,
transformation=transformation)
search_method = GreedySearch()
return attack
# GPT2(max_log_prob_diff=2)
return Attack(goal_function, constraints, transformation, search_method)

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@@ -12,7 +12,9 @@
"""
from textattack.shared.attack import Attack
from textattack.constraints.overlap import LevenshteinEditDistance
from textattack.constraints.semantics import WordEmbeddingDistance, RepeatModification, StopwordModification
from textattack.goal_functions import NonOverlappingOutput
from textattack.search_methods import GreedyWordSwapWIR
from textattack.transformations import WordSwapEmbedding
@@ -26,13 +28,22 @@ def Seq2SickCheng2018BlackBox(model, goal_function='non_overlapping'):
# seq2sick.
transformation = WordSwapEmbedding(max_candidates=50)
#
# Don't modify the same word twice or stopwords
#
constraints = [
RepeatModification(),
StopwordModification()
]
#
# In these experiments, we hold the maximum difference
# on edit distance (ϵ) to a constant 30 for each sample.
#
constraints.append(
LevenshteinEditDistance(30)
)
#
# Greedily swap words with "Word Importance Ranking".
#
attack = GreedyWordSwapWIR(goal_function, transformation=transformation,
constraints=[], max_depth=10)
search_method = GreedyWordSwapWIR()
return attack
return Attack(goal_function, constraints, transformation, search_method)

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@@ -27,14 +27,13 @@ def TextFoolerJin2019(model):
# results show that it's definitely 0.5.)
#
transformation = WordSwapEmbedding(max_candidates=50)
constraints = []
#
# Don't modify the same word twice or stopwords
#
constraints.append(
RepeatModfication(),
StopwordModification(textfooler_stopwords=True),
)
constraints = [
RepeatModification(),
StopwordModification(textfooler_stopwords=True)
]
#
# Minimum word embedding cosine similarity of 0.5.
#

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@@ -8,7 +8,8 @@
"""
from textattack.constraints.semantics import WordEmbeddingDistance
from textattack.shared.attack import Attack
from textattack.constraints.semantics import WordEmbeddingDistance, RepeatModification, StopwordModification
from textattack.constraints.semantics.sentence_encoders import UniversalSentenceEncoder, BERT
from textattack.constraints.grammaticality import PartOfSpeech, LanguageTool
from textattack.goal_functions import UntargetedClassification
@@ -25,13 +26,19 @@ def TextFoolerJin2019Adjusted(model, SE_thresh=0.98, sentence_encoder='bert'):
# (The paper claims 0.7, but analysis of the code and some empirical
# results show that it's definitely 0.5.)
#
transformation = WordSwapEmbedding(max_candidates=50, textfooler_stopwords=True)
transformation = WordSwapEmbedding(max_candidates=50)
#
# Don't modify the same word twice or stopwords
#
constraints = [
RepeatModification(),
StopwordModification()
]
#
# Minimum word embedding cosine similarity of 0.9.
#
constraints = []
constraints.append(
WordEmbeddingDistance(min_cos_sim=0.9)
WordEmbeddingDistance(min_cos_sim=0.9)
)
#
# Universal Sentence Encoder with a minimum angular similarity of ε = 0.7.
@@ -49,7 +56,7 @@ def TextFoolerJin2019Adjusted(model, SE_thresh=0.98, sentence_encoder='bert'):
# Do grammar checking
#
constraints.append(
LanguageTool(0)
LanguageTool(0)
)
#
@@ -60,7 +67,6 @@ def TextFoolerJin2019Adjusted(model, SE_thresh=0.98, sentence_encoder='bert'):
#
# Greedily swap words with "Word Importance Ranking".
#
attack = GreedyWordSwapWIR(goal_function, transformation=transformation,
constraints=constraints, max_depth=None)
search_method = GreedyWordSwapWIR()
return attack
return Attack(goal_function, constraints, transformation, search_method)

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@@ -24,14 +24,14 @@ class Constraint:
compatible_x_advs = []
for x_adv in x_adv_list:
try:
if self.check_compatibility(x_adv.attack-attrs['last_transformation']):
if self.check_compatibility(x_adv.attack_attrs['last_transformation']):
compatible_x_advs.append(x_adv)
else:
incompatible_x_advs.append(x_adv)
except KeyError:
raise KeyError('x_adv must have `last_transformation` attack_attr to apply GoogLM constraint')
filtered_x_advs = self._check_constraint_many(x, compatible_x_advs, original_text=original_text)
return filtered_x_advs + incompatible_x_advs
return list(filtered_x_advs) + incompatible_x_advs
def _check_constraint_many(self, x, x_adv_list, original_text=None):
return [x_adv for x_adv in x_adv_list

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@@ -3,7 +3,7 @@ import nltk
from textattack.constraints import Constraint
from textattack.shared import TokenizedText
from textattack.transformation import WordSwap
from textattack.transformations import WordSwap
class PartOfSpeech(Constraint):
""" Constraints word swaps to only swap words with the same part of speech.
@@ -50,7 +50,7 @@ class PartOfSpeech(Constraint):
after_ctx = x.words[i+1:min(i+5,len(x.words))]
cur_pos = self._get_pos(before_ctx, x_word, after_ctx)
replace_pos = self._get_pos(before_ctx, x_adv_word, after_ctx)
if not self._can_replace_pos(cur_post, replace_pos)
if not self._can_replace_pos(cur_pos, replace_pos):
return False
return True

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@@ -12,9 +12,9 @@ class ModificationConstraint(Constraint):
def __call__(self, x, transformation):
""" Returns the word indices in x which are able to be modified """
if not self.check_compatibility(self, transformation):
if not self.check_compatibility(transformation):
return True
return _get_modifiable_indices(x)
return self._get_modifiable_indices(x)
def _get_modifiable_indices(x):
raise NotImplementedError()

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@@ -93,7 +93,11 @@ class SentenceEncoder(Constraint):
x_list_text = []
x_adv_list_text = []
for x_adv in x_adv_list:
modified_index = x_adv.attack_attrs['modified_word_index']
#@TODO make this work when multiple indices have been modified
try:
modified_index = next(iter(x_adv.attack_attrs['newly_modified_indices']))
except KeyError:
raise KeyError('Cannot apply sentence encoder constraint without `newly_modified_indices`')
x_list_text.append(x.text_window_around_index(modified_index, self.window_size))
x_adv_list_text.append(x_adv.text_window_around_index(modified_index, self.window_size))
embeddings = self.encode(x_list_text + x_adv_list_text)

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@@ -1,5 +1,5 @@
from .search_method import SearchMethod
from .beam_search import BeamSearch
from .greedy_word_swap import GreedyWordSwap
from .greedy_search import GreedySearch
from .greedy_word_swap_wir import GreedyWordSwapWIR
from .genetic_algorithm import GeneticAlgorithm
from .search_method import SearchMethod

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@@ -1,6 +1,7 @@
from texattack.search_methods import SearchMethod
import numpy as np
from textattack.search_methods import SearchMethod
class BeamSearch(SearchMethod):
"""
An attack that greedily chooses from a list of possible
@@ -36,8 +37,7 @@ class BeamSearch(SearchMethod):
# in descending order and filling the beam from there.
best_indices = -scores.argsort()[:self.beam_width]
beam = [potential_next_beam[i] for i in best_indices]
return best_result
return best_result
def extra_repr_keys(self):
return ['beam_width']

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@@ -27,7 +27,7 @@ class GeneticAlgorithm(SearchMethod):
self.give_up_if_no_improvement = give_up_if_no_improvement
def check_transformation_compatibility(self, transformation):
return transformation.instance_of(WordSwap)
return transformation.consists_of(WordSwap)
def _replace_at_index(self, pop_member, idx):
"""

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@@ -1,6 +1,7 @@
import numpy as np
from textattack.search_methods import SearchMethod
from textattack.transformations import WordSwap
class GreedyWordSwapWIR(SearchMethod):
"""
@@ -23,17 +24,18 @@ class GreedyWordSwapWIR(SearchMethod):
}
def __init__(self, wir_method='unk'):
self.wir_method = wir_method
try:
self.replacement_str = self.WIR_TO_REPLACEMENT_STR[wir_method]
except KeyError:
raise KeyError(f'Word Importance Ranking method {wir_method} not recognized.')
def check_transformation_compatibility(self, transformation):
return transformation.instance_of(WordSwap)
return transformation.consists_of(WordSwap)
def __call__(self, initial_result):
original_tokenized_text = intial_result.tokenized_text
cur_result = intial_result
tokenized_text = initial_result.tokenized_text
cur_result = initial_result
# Sort words by order of importance
len_text = len(tokenized_text.words)
@@ -41,19 +43,19 @@ class GreedyWordSwapWIR(SearchMethod):
leave_one_texts = \
[tokenized_text.replace_word_at_index(i,self.replacement_str) for i in range(len_text)]
leave_one_scores = np.array([result.score for result in \
self.get_goal_results(leave_one_texts, intial_result.output)])
self.get_goal_results(leave_one_texts, initial_result.output)])
index_order = (-leave_one_scores).argsort()
i = 0
while i < len(index_order):
transformed_text_candidates = self.get_transformations(
cur_result.tokenized_text,
original_text=original_tokenized_text,
original_text=initial_result.tokenized_text,
indices_to_modify=[index_order[i]])
i += 1
if len(transformed_text_candidates) == 0:
continue
results = sorted(self.get_goal_results(transformed_text_candidates, intial_result.output),
results = sorted(self.get_goal_results(transformed_text_candidates, initial_result.output),
key=lambda x: -x.score)
# Skip swaps which don't improve the score
if results[0].score > cur_result.score:

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@@ -2,6 +2,6 @@ from . import scripts
from . import utils
from . import validators
from .attack import Attack
from .tokenized_text import TokenizedText
from .word_embedding import WordEmbedding
from .attack import Attack

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@@ -6,7 +6,7 @@ import random
from textattack.shared import utils
from textattack.constraints import Constraint, ModificationConstraint
from textattack.shared import TokenizedText
from textattack.attack_results import SkippedAttackResult, SuccessfulAttackResult, FailedAtttackResult
from textattack.attack_results import SkippedAttackResult, SuccessfulAttackResult, FailedAttackResult
class Attack:
"""
@@ -39,11 +39,7 @@ class Attack:
else:
raise NameError('Cannot instantiate attack without tokenizer')
self.transformation = transformation
self.is_black_box = True
for transformation in transformations:
if not transformation.is_black_box:
self.is_black_box = False
break
self.is_black_box = getattr(transformation, 'is_black_box', True)
if not self.search_method.check_transformation_compatibility(self.transformation):
raise ValueError('SearchMethod {self.search_method} incompatible with transformation {self.transformation}')
@@ -51,7 +47,7 @@ class Attack:
self.constraints = []
self.modification_constraints = []
for constraint in constraints:
is isinstance(constraint, ModiifcationConstraint):
if isinstance(constraint, ModificationConstraint):
self.modification_constraints.append(constraint)
else:
self.constraints.append(constraint)
@@ -138,7 +134,7 @@ class Attack:
"""
Perturbs `tokenized_text` from initial_result until goal is reached.
"""
final_result = search_method(initial_result)
final_result = self.search_method(initial_result)
if final_result.succeeded:
return SuccessfulAttackResult(initial_result, final_result)
else:

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@@ -107,7 +107,7 @@ CONSTRAINT_CLASS_NAMES = {
'thought-vector': 'textattack.constraints.semantics.sentence_encoders.ThoughtVector',
'use': 'textattack.constraints.semantics.sentence_encoders.UniversalSentenceEncoder',
'repeat': 'textattack.constraints.semantics.RepeatModification',
'stopword': 'textattack.constraints.semantics.StopwordModification',.
'stopword': 'textattack.constraints.semantics.StopwordModification',
#
# Grammaticality constraints
#
@@ -156,7 +156,7 @@ def get_args():
choices=MODEL_CLASS_NAMES.keys(), help='The classification model to attack.')
parser.add_argument('--constraints', type=str, required=False, nargs='*',
default=[],
default=['repeat', 'stopword'],
help=('Constraints to add to the attack. Usage: "--constraints {constraint}:{arg_1}={value_1},{arg_3}={value_3}". Choices: ' + str(CONSTRAINT_CLASS_NAMES.keys())))
parser.add_argument('--out-dir', type=str, required=False, default=None,

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@@ -34,6 +34,8 @@ class TokenizedText:
self.attack_attrs = attack_attrs
if 'modified_indices' not in attack_attrs:
attack_attrs['modified_indices'] = set()
if 'stopword_indices' not in attack_attrs:
attack_attrs['stopword_indices'] = set()
def __eq__(self, other):
return (self.text == other.text) and (self.attack_attrs == other.attack_attrs)
@@ -46,10 +48,10 @@ class TokenizedText:
if textfooler_stopwords:
self.stopwords = set(['a', 'about', 'above', 'across', 'after', 'afterwards', 'again', 'against', 'ain', 'all', 'almost', 'alone', 'along', 'already', 'also', 'although', 'am', 'among', 'amongst', 'an', 'and', 'another', 'any', 'anyhow', 'anyone', 'anything', 'anyway', 'anywhere', 'are', 'aren', "aren't", 'around', 'as', 'at', 'back', 'been', 'before', 'beforehand', 'behind', 'being', 'below', 'beside', 'besides', 'between', 'beyond', 'both', 'but', 'by', 'can', 'cannot', 'could', 'couldn', "couldn't", 'd', 'didn', "didn't", 'doesn', "doesn't", 'don', "don't", 'down', 'due', 'during', 'either', 'else', 'elsewhere', 'empty', 'enough', 'even', 'ever', 'everyone', 'everything', 'everywhere', 'except', 'first', 'for', 'former', 'formerly', 'from', 'hadn', "hadn't", 'hasn', "hasn't", 'haven', "haven't", 'he', 'hence', 'her', 'here', 'hereafter', 'hereby', 'herein', 'hereupon', 'hers', 'herself', 'him', 'himself', 'his', 'how', 'however', 'hundred', 'i', 'if', 'in', 'indeed', 'into', 'is', 'isn', "isn't", 'it', "it's", 'its', 'itself', 'just', 'latter', 'latterly', 'least', 'll', 'may', 'me', 'meanwhile', 'mightn', "mightn't", 'mine', 'more', 'moreover', 'most', 'mostly', 'must', 'mustn', "mustn't", 'my', 'myself', 'namely', 'needn', "needn't", 'neither', 'never', 'nevertheless', 'next', 'no', 'nobody', 'none', 'noone', 'nor', 'not', 'nothing', 'now', 'nowhere', 'o', 'of', 'off', 'on', 'once', 'one', 'only', 'onto', 'or', 'other', 'others', 'otherwise', 'our', 'ours', 'ourselves', 'out', 'over', 'per', 'please','s', 'same', 'shan', "shan't", 'she', "she's", "should've", 'shouldn', "shouldn't", 'somehow', 'something', 'sometime', 'somewhere', 'such', 't', 'than', 'that', "that'll", 'the', 'their', 'theirs', 'them', 'themselves', 'then', 'thence', 'there', 'thereafter', 'thereby', 'therefore', 'therein', 'thereupon', 'these', 'they','this', 'those', 'through', 'throughout', 'thru', 'thus', 'to', 'too','toward', 'towards', 'under', 'unless', 'until', 'up', 'upon', 'used', 've', 'was', 'wasn', "wasn't", 'we', 'were', 'weren', "weren't", 'what', 'whatever', 'when', 'whence', 'whenever', 'where', 'whereafter', 'whereas', 'whereby', 'wherein', 'whereupon', 'wherever', 'whether', 'which', 'while', 'whither', 'who', 'whoever', 'whole', 'whom', 'whose', 'why', 'with', 'within', 'without', 'won', "won't", 'would', 'wouldn', "wouldn't", 'y', 'yet', 'you', "you'd", "you'll", "you're", "you've", 'your', 'yours', 'yourself', 'yourselves'])
attack_attrs['stopword_indices'] = set()
self.attack_attrs['stopword_indices'] = set()
for i, word in enumerate(self.words):
if word.lower() in self.stopwords:
attack_attrs['stopword_indices'].add(i)
self.attack_attrs['stopword_indices'].add(i)
def delete_tensors(self):
""" Delete tensors to clear up GPU space. Only should be called

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@@ -7,21 +7,21 @@ class Transformation:
"""
self.is_black_box = True
def __call__(self, tokenized_text, modification_constraints=[], indices_to_modify=None):
""" Returns a list of all possible transformations for `tokenized_text`."""
if indices_to_modify is None:
indices_to_modify = set(range(len(tokenized_text.words)))
else:
indices_to_modify = set(indices_to_modify)
for constraint in modification_constraints:
if constraint.check_compatibility(self):
indices_to_modify = indices_to_modify & constraint(tokenized_text, self)
transformed_texts = _get_transformations(tokenized_text, indices_to_modify)
transformed_texts = self._get_transformations(tokenized_text, indices_to_modify)
for text in transformed_texts:
text.attack_attrs['last_transformation'] = self
return transformed_texts
def _get_transformations(self, tokenized_text, indices_to_modify)
def _get_transformations(self, tokenized_text, indices_to_modify):
raise NotImplementedError()
def extra_repr_keys(self):