Unittests for esphome python code (#931)

tests/unit_tests/conftest.py

@@ -0,0 +1,30 @@
+"""
+ESPHome Unittests
+~~~~~~~~~~~~~~~~~
+
+Configuration file for unit tests.
+
+If adding unit tests ensure that they are fast. Slower integration tests should
+not be part of a unit test suite.
+
+"""
+import sys
+import pytest
+
+from pathlib import Path
+
+
+here = Path(__file__).parent
+
+# Configure location of package root
+package_root = here.parent.parent
+sys.path.insert(0, package_root.as_posix())
+
+
+@pytest.fixture
+def fixture_path() -> Path:
+    """
+    Location of all fixture files.
+    """
+    return here / "fixtures"
+