resolves #1: Implemented plugin tests

.github/workflows/python_tests.yml

@@ -0,0 +1,34 @@
+# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
+
+name: Python package
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: [3.5, 3.6, 3.7, 3.8]
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v1
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install flake8 pytest
+        python setup.py develop
+        if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+    - name: Test with pytest
+      run: |
+        pytest

pytest.ini

@@ -0,0 +1,4 @@
+[pytest]
+testpaths = tests
+addopts = -v --tb=long
+filterwarnings = ignore::DeprecationWarning

tests/test_plugin.py

@@ -0,0 +1,27 @@
+import os
+import pytest
+pytest_plugins = "pytester"
+
+def test_xfail(testdir):
+    testdir.makepyfile("""
+        def test_one():
+            assert True
+
+        def test_two():
+            assert False
+    """)
+    # Store the failure in expect file
+    result_before_xfail = testdir.runpytest("-vv", "--update-xfail")
+    result_before_xfail.assert_outcomes(
+        passed=1,
+        failed=1
+    )
+
+    # Execute the tests
+    result = testdir.runpytest("-vv")
+
+    # Assert that the expected failure should be marked xfail
+    result.assert_outcomes(
+        passed=1,
+        xfailed=1
+    )