1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
|
# This file is part of Hypothesis, which may be found at
# https://github.com/HypothesisWorks/hypothesis/
#
# Copyright the Hypothesis Authors.
# Individual contributors are listed in AUTHORS.rst and the git log.
#
# This Source Code Form is subject to the terms of the Mozilla Public License,
# v. 2.0. If a copy of the MPL was not distributed with this file, You can
# obtain one at https://mozilla.org/MPL/2.0/.
from random import Random
import pytest
from hypothesis import HealthCheck, settings
from hypothesis.errors import Flaky
from hypothesis.internal.conjecture.data import ConjectureData, Status, StopTest
from hypothesis.internal.conjecture.datatree import DataTree
from hypothesis.internal.conjecture.engine import ConjectureRunner
TEST_SETTINGS = settings(
max_examples=5000, database=None, suppress_health_check=HealthCheck.all()
)
def runner_for(*examples):
if len(examples) == 1 and isinstance(examples[0], list):
examples = examples[0]
def accept(tf):
runner = ConjectureRunner(tf, settings=TEST_SETTINGS, random=Random(0))
runner.exit_with = lambda reason: None
ran_examples = []
for e in examples:
e = bytes(e)
data = runner.cached_test_function(e)
ran_examples.append((e, data))
for e, d in ran_examples:
rewritten, status = runner.tree.rewrite(e)
assert status == d.status
assert rewritten == d.buffer
return runner
return accept
def test_can_lookup_cached_examples():
@runner_for(b"\0\0", b"\0\1")
def runner(data):
data.draw_bits(8)
data.draw_bits(8)
def test_can_lookup_cached_examples_with_forced():
@runner_for(b"\0\0", b"\0\1")
def runner(data):
data.write(b"\1")
data.draw_bits(8)
def test_can_detect_when_tree_is_exhausted():
@runner_for(b"\0", b"\1")
def runner(data):
data.draw_bits(1)
assert runner.tree.is_exhausted
def test_can_detect_when_tree_is_exhausted_variable_size():
@runner_for(b"\0", b"\1\0", b"\1\1")
def runner(data):
if data.draw_bits(1):
data.draw_bits(1)
assert runner.tree.is_exhausted
def test_one_dead_branch():
@runner_for([[0, i] for i in range(16)] + [[i] for i in range(1, 16)])
def runner(data):
i = data.draw_bits(4)
if i > 0:
data.mark_invalid()
data.draw_bits(4)
assert runner.tree.is_exhausted
def test_non_dead_root():
@runner_for(b"\0\0", b"\1\0", b"\1\1")
def runner(data):
data.draw_bits(1)
data.draw_bits(1)
def test_can_reexecute_dead_examples():
@runner_for(b"\0\0", b"\0\1", b"\0\0")
def runner(data):
data.draw_bits(1)
data.draw_bits(1)
def test_novel_prefixes_are_novel():
def tf(data):
for _ in range(4):
data.write(b"\0")
data.draw_bits(2)
runner = ConjectureRunner(tf, settings=TEST_SETTINGS, random=Random(0))
for _ in range(100):
prefix = runner.tree.generate_novel_prefix(runner.random)
example = prefix + bytes(8 - len(prefix))
assert runner.tree.rewrite(example)[1] is None
result = runner.cached_test_function(example)
assert runner.tree.rewrite(example)[0] == result.buffer
def test_overruns_if_not_enough_bytes_for_block():
runner = ConjectureRunner(
lambda data: data.draw_bytes(2), settings=TEST_SETTINGS, random=Random(0)
)
runner.cached_test_function(b"\0\0")
assert runner.tree.rewrite(b"\0")[1] == Status.OVERRUN
def test_overruns_if_prefix():
runner = ConjectureRunner(
lambda data: [data.draw_bits(1) for _ in range(2)],
settings=TEST_SETTINGS,
random=Random(0),
)
runner.cached_test_function(b"\0\0")
assert runner.tree.rewrite(b"\0")[1] == Status.OVERRUN
def test_stores_the_tree_flat_until_needed():
@runner_for(bytes(10))
def runner(data):
for _ in range(10):
data.draw_bits(1)
data.mark_interesting()
root = runner.tree.root
assert len(root.bit_lengths) == 10
assert len(root.values) == 10
assert root.transition.status == Status.INTERESTING
def test_split_in_the_middle():
@runner_for([0, 0, 2], [0, 1, 3])
def runner(data):
data.draw_bits(1)
data.draw_bits(1)
data.draw_bits(4)
data.mark_interesting()
root = runner.tree.root
assert len(root.bit_lengths) == len(root.values) == 1
assert list(root.transition.children[0].values) == [2]
assert list(root.transition.children[1].values) == [3]
def test_stores_forced_nodes():
@runner_for(bytes(3))
def runner(data):
data.draw_bits(1, forced=0)
data.draw_bits(1)
data.draw_bits(1, forced=0)
data.mark_interesting()
root = runner.tree.root
assert root.forced == {0, 2}
def test_correctly_relocates_forced_nodes():
@runner_for([0, 0], [1, 0])
def runner(data):
data.draw_bits(1)
data.draw_bits(1, forced=0)
data.mark_interesting()
root = runner.tree.root
assert root.transition.children[1].forced == {0}
assert root.transition.children[0].forced == {0}
def test_can_go_from_interesting_to_valid():
tree = DataTree()
data = ConjectureData.for_buffer(b"", observer=tree.new_observer())
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"", observer=tree.new_observer())
with pytest.raises(StopTest):
data.conclude_test(Status.VALID)
def test_going_from_interesting_to_invalid_is_flaky():
tree = DataTree()
data = ConjectureData.for_buffer(b"", observer=tree.new_observer())
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"", observer=tree.new_observer())
with pytest.raises(Flaky):
data.conclude_test(Status.INVALID)
def test_concluding_at_prefix_is_flaky():
tree = DataTree()
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
data.draw_bits(1)
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"", observer=tree.new_observer())
with pytest.raises(Flaky):
data.conclude_test(Status.INVALID)
def test_concluding_with_overrun_at_prefix_is_not_flaky():
tree = DataTree()
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
data.draw_bits(1)
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"", observer=tree.new_observer())
with pytest.raises(StopTest):
data.conclude_test(Status.OVERRUN)
def test_changing_n_bits_is_flaky_in_prefix():
tree = DataTree()
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
data.draw_bits(1)
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
with pytest.raises(Flaky):
data.draw_bits(2)
def test_changing_n_bits_is_flaky_in_branch():
tree = DataTree()
for i in [0, 1]:
data = ConjectureData.for_buffer([i], observer=tree.new_observer())
data.draw_bits(1)
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
with pytest.raises(Flaky):
data.draw_bits(2)
def test_extending_past_conclusion_is_flaky():
tree = DataTree()
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
data.draw_bits(1)
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"\1\0", observer=tree.new_observer())
data.draw_bits(1)
with pytest.raises(Flaky):
data.draw_bits(1)
def test_changing_to_forced_is_flaky():
tree = DataTree()
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
data.draw_bits(1)
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"\1\0", observer=tree.new_observer())
with pytest.raises(Flaky):
data.draw_bits(1, forced=0)
def test_changing_value_of_forced_is_flaky():
tree = DataTree()
data = ConjectureData.for_buffer(b"\1", observer=tree.new_observer())
data.draw_bits(1, forced=1)
with pytest.raises(StopTest):
data.conclude_test(Status.INTERESTING)
data = ConjectureData.for_buffer(b"\1\0", observer=tree.new_observer())
with pytest.raises(Flaky):
data.draw_bits(1, forced=0)
def test_does_not_truncate_if_unseen():
tree = DataTree()
b = bytes([1, 2, 3, 4])
assert tree.rewrite(b) == (b, None)
def test_truncates_if_seen():
tree = DataTree()
b = bytes([1, 2, 3, 4])
data = ConjectureData.for_buffer(b, observer=tree.new_observer())
data.draw_bits(8)
data.draw_bits(8)
data.freeze()
assert tree.rewrite(b) == (b[:2], Status.VALID)
def test_child_becomes_exhausted_after_split():
tree = DataTree()
data = ConjectureData.for_buffer([0, 0], observer=tree.new_observer())
data.draw_bits(8)
data.draw_bits(8, forced=0)
data.freeze()
data = ConjectureData.for_buffer([1, 0], observer=tree.new_observer())
data.draw_bits(8)
data.draw_bits(8)
data.freeze()
assert not tree.is_exhausted
assert tree.root.transition.children[0].is_exhausted
def test_will_generate_novel_prefix_to_avoid_exhausted_branches():
tree = DataTree()
data = ConjectureData.for_buffer([1], observer=tree.new_observer())
data.draw_bits(1)
data.freeze()
data = ConjectureData.for_buffer([0, 1], observer=tree.new_observer())
data.draw_bits(1)
data.draw_bits(8)
data.freeze()
prefix = list(tree.generate_novel_prefix(Random(0)))
assert len(prefix) == 2
assert prefix[0] == 0
def test_will_mark_changes_in_discard_as_flaky():
tree = DataTree()
data = ConjectureData.for_buffer([1, 1], observer=tree.new_observer())
data.start_example(10)
data.draw_bits(1)
data.stop_example()
data.draw_bits(1)
data.freeze()
data = ConjectureData.for_buffer([1, 1], observer=tree.new_observer())
data.start_example(10)
data.draw_bits(1)
with pytest.raises(Flaky):
data.stop_example(discard=True)
|
