Add basic unit tests for precipitation

django/climate_change_api/indicators/tests/test_unit_converters.py

@@ -1,46 +1,49 @@
 from django.test import TestCase
-from indicators.unit_converters import TemperatureConverter
+from indicators.tests.mixins import ConverterTestMixin
+from indicators.unit_converters import TemperatureConverter, PrecipitationConverter
 
 
-class TemperatureConverterTestCase(TestCase):
-    def test_conversions(self):
-        cases = {
-            ('F', 'K'): [
-                (0, 255.372222),
-                (32, 273.15),
-                (73.45, 296.17778)
-            ],
-            ('K', 'F'): [
-                (0, -459.67),
-                (276.3, 37.67)
-            ],
-            ('K', 'C'): [
-                (0, -273.15),
-                (295.3, 22.15)
-            ],
-            ('C', 'F'): [
-                (-40, -40),
-                (0, 32),
-                (10, 50),
-                (100, 212),
-                (23.2, 73.76)
-            ],
-            ('F', 'C'): [
-                (80, 26.6667),
-                (73.2, 22.888889),
-                (-40, -40),
-                (0, -17.77778),
-                (212, 100),
-                (32, 0)
-            ]
-        }
+class TemperatureConverterTestCase(ConverterTestMixin, TestCase):
+    converter_class = TemperatureConverter
+    cases = {
+        ('F', 'K'): [
+            (0, 255.372222),
+            (32, 273.15),
+            (73.45, 296.17778)
+        ],
+        ('K', 'F'): [
+            (0, -459.67),
+            (276.3, 37.67)
+        ],
+        ('K', 'C'): [
+            (0, -273.15),
+            (295.3, 22.15)
+        ],
+        ('C', 'F'): [
+            (-40, -40),
+            (0, 32),
+            (10, 50),
+            (100, 212),
+            (23.2, 73.76)
+        ],
+        ('F', 'C'): [
+            (80, 26.6667),
+            (73.2, 22.888889),
+            (-40, -40),
+            (0, -17.77778),
+            (212, 100),
+            (32, 0)
+        ]
+    }
 
-        for units, tests in cases.iteritems():
-            converter = TemperatureConverter.get(*units)
 
-            for start, expected in tests:
-                value = converter(start)
-                self.assertAlmostEqual(value, expected,
-                                       places=3,
-                                       msg='Failed assertion that %f %s = %f %s, got %f %s' %
-                                       (start, units[0], expected, units[1], value, units[1]))
+class PrecipitationConverterTestCase(ConverterTestMixin, TestCase):
+    converter_class = PrecipitationConverter
+    cases = {
+        ('kg/m^2/s', 'kg/m^2/day'): [
+            (1, 86400)
+        ],
+        ('kg/m^2/day', 'kg/m^2/s'): [
+            (86400, 1)
+        ]
+    }

django/climate_change_api/indicators/unit_converters.py

@@ -30,7 +30,7 @@ class LinearConverter(UnitConverter):
     units = {}
 
     def __init__(self, start, end):
-        self.ratio = self.units[end] / self.units[start]
+        self.ratio = 1.0 * self.units[end] / self.units[start]
 
     def convert(self, value):
         return value * self.ratio