[Pytest] Marker

Markers are used to set various features or attributes to tests, and can use related API to set metadata on tests.

usefixtures

• Import fixture into tests.

import pytest

@pytest.fixture()
def init_funtion():
  print("INIT")

@pytest.mark.usefixtures("init_funtion")
class TestCases():
  def test_case1(self):
    print("Case1")

""" 
Result 
"""
# INIT
# Case1

filterwarnings

• Filter certain warnings of test

import pytest
import warnings

def warn_function():
  warnings.warn("WARNING", DeprecationWarning)

@pytest.mark.filterwarnings("ignore::DeprecationWarning")
def test_case1():
  warn_function()

skip / skipif

• Always skip a test or a certain condition is met

import pytest

@pytest.fixture(scope="class")
def init_funtion():
  print("INIT")

@pytest.mark.usefixtures("init_funtion")
class TestCases():
  @pytest.mark.skip(reason="SKIP")
  def test_case1(self):
    print("Case1")
  
  def test_case2(self):
    print("Case2")

""" 
Result 
"""
# INIT
# SKIP
# Case2

import sys
import pytest

@pytest.fixture(scope="class")
def init_funtion():
  print("INIT")

@pytest.mark.usefixtures("init_funtion")
class TestCases():
  # Skipped when run on an interpreter earlier than Python3.10
  @pytest.mark.skipif(sys.version_info < (3, 10), reason="SKIP")
  def test_case1(self):
    print("Case1")
  
  def test_case2(self):
    print("Case2")

""" 
Result 
"""
# INIT
# SKIP
# Case2

xfail

• Produce an expected failure outcome if a certain condition is met

import sys
import pytest

@pytest.fixture(scope="class")
def init_funtion():
  print("INIT")

@pytest.mark.usefixtures("init_funtion")
class TestCases():
  @pytest.mark.xfail(reason="Expected")
  def test_case1(self):
    print("Case1")
    assert "A" == "B"
  
  # Expected Fail when run on an interpreter earlier than Python3.10
  @pytest.mark.xfail(sys.version_info < (3, 10), reason="Version Too Old")
  def test_case2(self):
    print("Case2")

  # If a test should be marked as XFAIL but should not be even executed
  @pytest.mark.xfail(run=False)
  def test_case3(self):
    print("Case3")

  @pytest.mark.xfail(reason="Expected")
  def test_case4(self):
    print("Case4")

""" 
Result 
"""
# INIT
# Case1
# XFAIL (Expected)
# Case2
# XPASS (Version Too Old)
# XFAIL ([NOTRUN])
# Case4
# XPASS (Expected)

parametrize

• Perform multiple calls to the same test

import pytest

@pytest.fixture(scope="class")
def init_funtion():
  print("INIT")

@pytest.mark.usefixtures("init_funtion")
class TestCases():
  @pytest.mark.parametrize("a,b,c", [(1, 2, 3), (1, 2, 4)])
  def test_case1(self, a, b, c):
    print("Case1")
    assert a + b == c

""" 
Result 
"""
# INIT
# Case1
# PASSED
# Case1
# FAILED