Hypothesis is a Python library for property-based testing; creating unit tests with pseudo-randomly generated data.
Questions about the testing library Hypothesis:
Questions tagged [python-hypothesis]
182 questions
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vote
1 answer
generate an array of random numbers with hypothesis in python
I have a sorting algorithm that seems to work fine but I would like to test it more with random samples.
So to test it, I'm trying to generate random arrays with hypothesis in Python, I would like the arrays to be of various lengths and contain any…
user206904
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1 answer
Python Hypothesis package: can I ensure that certain values are used?
Problem Statement
Below is a toy example that is close to what I am trying to do.
@given(
idx_start=integers(min_value=0, max_value=100000),
idx_window=integers(min_value=0, max_value=100000),
)
def test_calc_max(conftest_df, idx_start,…
Mike Williamson
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vote
3 answers
How do I control a random seed with Pytest and Hypothesis?
I have a test which executes a function which uses random things. I would like to use hypothesis (or something else ?) to run it several times and know, when it fails, which random seed was used.
How can I do that?
My goal is to test my code several…
bux
- 7,087
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2 answers
How to execute Python functions using Hypothesis' composite strategy?
I am trying to execute a function decorated with Hypothesis' @strategy.composite decorator.
I know I can test functions using the @given decorator, such as -
from hypothesis import given
from hypothesis import strategies as…
Pratyush Das
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1 answer
How to implement dependant columns in hypothesis dataframes
I am using hypothesis dataframes to implement a dataframe in which start_time and end_time are two columns. Here is a chunck:
import hypothesis.strategies as st
import logging
import datetime
from hypothesis import given
from…
GGJON
- 325
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1 answer
Hypothesis does not seem to honor the maxfail argument of pytest
In spite of specifying maxfail=1, hypothesis seems to continue generating examples and running them and failing much later.
Is there a workaround?
Here is a small example:
from hypothesis.stateful import invariant, rule,…
sureshvv
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3 answers
How to build a strategy to create array of tuples with pairs of identical values?
I'd like to generate a strategy for NumPy testing with an output like:
array([[-2, -2],
[-3, -3],
[5, 5],
[-1, -1]], dtype=int16)
What I tried was:
import numpy as np
from hypothesis.strategies import integers
from…
Marcin Charęziński
- 47
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1
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1 answer
@composite vs flatmap in complex strategies
hypothesis allows two different ways to define derived strategies, @composite and flatmap. As far as I can tell the former can do anything the latter can do. However, the implementation of the numpy arrays strategy, speaks of some hidden costs
#…
Marten
- 1,336
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2 answers
Hypothesis search strategy for dictionaries with different types of values
I am trying to generate dictionaries containing different python types as values using the hypothesis module.
For lists I can do this simply using the expression
from hypothesis import given
import hypothesis.strategies as st
@given(
st.lists(
…
DragonTux
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1
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2 answers
Pytest/Hypothesis not matching string as expected
I am testing a validate function I am using with Sanic.
def validate(val):
try:
if isinstance(val, bool): # Here because the int(val) line will success with int(True)/int(False)
raise ValueError()
if isinstance(val,…
NewGuy
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1
vote
1 answer
How to see the "Bundle" output of Hypothesis Python library? (Stateful testing)
When using the hypothesis library and performing stateful testing, how can I see or output the Bundle "services" the library is trying on my code?
Example
import hypothesis.strategies as st
from hypothesis.strategies import integers
from…
Aniket
- 11
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1 answer
xfail single hypothesis case using pytest?
Using pytest, I set specific parameters to fail as expected.
My testing suite uses hypothesis though. These is a bug that we know about that we don't intend to fix in this version of the API. It's already documented and the time it will takes to…
NewGuy
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1
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1 answer
Declare relationship between two arguments generated by hypothesis
I am using hypothesis for testing, and I wanted to establish a relationship between two arguments of a test. I am aware of assume, but that seems quite wasteful when I know the constraints beforehand.
Here's a minimal example:
from datetime import…
suvayu
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1 answer
Why strategies.permutations does not provide the smallest set of permutations?
I wrote a test to verify a given function behaves correctly for any given permutation of a list specified as input.
Using the hypothesis python package I've tried to construct this test case. However, the list of permutations generated contains many…
Jir
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2 answers
Recursive strategies with additional parameters in Hypothesis
Using recursive, I can generate simple ASTs, e.g.
from hypothesis import *
from hypothesis.strategies import *
def trees():
base = integers(min_value=1, max_value=10).map(lambda n: 'x' + str(n))
@composite
def extend(draw, children):
…
Alexey Romanov
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