Add bunch of RouterData tests

tests/components/huawei_lte.py

@@ -0,0 +1,42 @@
+"""Huawei LTE component tests."""
+import pytest
+
+from homeassistant.components import huawei_lte
+
+
+@pytest.fixture(autouse=True)
+def routerdata():
+    """Set up a router data for testing."""
+    rd = huawei_lte.RouterData(None)
+    rd.device_information = dict(
+        SoftwareVersion="1.0",
+        nested=dict(foo="bar"),
+    )
+    return rd
+
+
+async def test_routerdata_get_nonexistent_leaf(routerdata):
+    """Test that accessing a nonexistent leaf element raises KeyError."""
+    with pytest.raises(KeyError):
+        routerdata["device_information.foo"]
+
+
+async def test_routerdata_get_nonexistent_leaf_path(routerdata):
+    """Test that accessing a nonexistent long path raises KeyError."""
+    with pytest.raises(KeyError):
+        routerdata["device_information.long.path.foo"]
+
+
+async def test_routerdata_get_simple(routerdata):
+    """Test that accessing a short, simple path works."""
+    assert routerdata["device_information.SoftwareVersion"] == "1.0"
+
+
+async def test_routerdata_get_longer(routerdata):
+    """Test that accessing a longer path works."""
+    assert routerdata["device_information.nested.foo"] == "bar"
+
+
+async def test_routerdata_get_dict(routerdata):
+    """Test that returning an intermediate dict works."""
+    assert routerdata["device_information.nested"] == dict(foo="bar")