如何动态 select 一个 pytest 夹具？

Question

import pytest


@pytest.fixture()
def fixture1(fixture_a):
    print('In fixture 1')
    <do>
    step a
    step b
    <end>
    return <some object1> 



@pytest.fixture()
def fixture2(fixture_b):
    print('In fixture 2')
    <do>
    step x
    step y
    <end>
    return <some object2> 


def decide():
    a = 1
    if a == 1:
        return fixture1: Object1
    else:
        return fixture2: Object2


def test_me():
    res = decide()
    assert res == Object

I have two fixtures arg1 and arg2, now I want to return one of the fixture to the test but this has to be dynamic selection based on a condition. How to do this?

UPDATE: The fixtures arg1 and arg2 have a chain of dependency and they are being used in different tests.

Also, decide function needs to be used in multiple tests.

Answer 1

You can pass the arg1 and arg2 to test and test the condition itself.

def decide():
    a = 1
    if a == 1:
        return 1
    else:
        return 2

def test_me(fixture1, fixture2):
    arg = decide()
    if arg == 1:
        assert fixture1 == 1
    else:
        assert fixture2 == 2

Answer 2

I guess that can help - having fixture builder what runs functions(convert fixtures A,B to functions) in case of condition:

def arg1():
    print('In arg 1')
    return 1

def arg2():
    print('In arg 2')
    return 2

@pytest.fixture
def env_builder():
    if condition:
        return arg1()
    else
        return arg2()

def test_smth(env_builder):
   assert 2 == env_builder

your condition is up to you, os.getenv('environment'), or might positional cli argument while running tests