Move temperature display helper from components to helpers (#10555)

tests/helpers/test_temperature.py

@@ -0,0 +1,49 @@
+"""Tests Home Assistant temperature helpers."""
+import unittest
+
+from tests.common import get_test_home_assistant
+
+from homeassistant.const import (
+    TEMP_CELSIUS, PRECISION_WHOLE, TEMP_FAHRENHEIT, PRECISION_HALVES,
+    PRECISION_TENTHS)
+from homeassistant.helpers.temperature import display_temp
+from homeassistant.util.unit_system import METRIC_SYSTEM
+
+TEMP = 24.636626
+
+
+class TestHelpersTemperature(unittest.TestCase):
+    """Setup the temperature tests."""
+
+    def setUp(self):
+        """Setup the tests."""
+        self.hass = get_test_home_assistant()
+        self.hass.config.unit_system = METRIC_SYSTEM
+
+    def tearDown(self):
+        """Stop down stuff we started."""
+        self.hass.stop()
+
+    def test_temperature_not_a_number(self):
+        """Test that temperature is a number."""
+        temp = "Temperature"
+        with self.assertRaises(Exception) as context:
+            display_temp(self.hass, temp, TEMP_CELSIUS, PRECISION_HALVES)
+
+        self.assertTrue("Temperature is not a number: {}".format(temp)
+                        in str(context.exception))
+
+    def test_celsius_halves(self):
+        """Test temperature to celsius rounding to halves."""
+        self.assertEqual(24.5, display_temp(
+            self.hass, TEMP, TEMP_CELSIUS, PRECISION_HALVES))
+
+    def test_celsius_tenths(self):
+        """Test temperature to celsius rounding to tenths."""
+        self.assertEqual(24.6, display_temp(
+            self.hass, TEMP, TEMP_CELSIUS, PRECISION_TENTHS))
+
+    def test_fahrenheit_wholes(self):
+        """Test temperature to fahrenheit rounding to wholes."""
+        self.assertEqual(-4, display_temp(
+            self.hass, TEMP, TEMP_FAHRENHEIT, PRECISION_WHOLE))