No longer create registry in public module

2 files changed, 21 insertions, 18 deletions

diff --git a/szilagyi/__init__.py b/szilagyi/__init__.py
index 8d294d7..67da4a8 100644
--- a/szilagyi/__init__.py
+++ b/szilagyi/__init__.py
@@ -13,14 +13,11 @@ There is only one function provided, so the use should be straight-forward. For
 	-4.88
 """
 
-from pint import UnitRegistry
 from pint.quantity import Quantity
 
 from ._nomogram import calculate_swi as _calculate_swi
 from ._nomogram import MAX_TEMPERATURE_DIFFERENCE, MAX_CONVECTIVE_CLOUD_DEPTH
 
-_registry = UnitRegistry()
-
 
 def calculate_swi(temperature_difference: Quantity, convective_cloud_depth: Quantity) -> float:
 	"""
@@ -30,12 +27,12 @@ def calculate_swi(temperature_difference: Quantity, convective_cloud_depth: Quan
 	of the original nomogram. The maximum values are available as MAX_TEMPERATURE_DIFFERENCE and MAX_CONVECTIVE_CLOUD_DEPTH
 	constants.
 	"""
-	if not temperature_difference.is_compatible_with(_registry.C):
+	if not temperature_difference.is_compatible_with("C"):
 		raise ValueError("temperature_difference must be convertible to Celsius degrees")
-	if not convective_cloud_depth.is_compatible_with(_registry.ft):
+	if not convective_cloud_depth.is_compatible_with("ft"):
 		raise ValueError("convective_cloud_depth must be convertible to Feet")
-	temperature_difference = temperature_difference.m_as(_registry.C)
-	convective_cloud_depth = convective_cloud_depth.m_as(_registry.ft)
+	temperature_difference = temperature_difference.m_as("C")
+	convective_cloud_depth = convective_cloud_depth.m_as("ft")
 	if temperature_difference < 0 or temperature_difference > MAX_TEMPERATURE_DIFFERENCE:
 		raise ValueError(f"temperature_difference must be within <0, {MAX_TEMPERATURE_DIFFERENCE}> range")
 	if convective_cloud_depth < 0 or convective_cloud_depth > MAX_CONVECTIVE_CLOUD_DEPTH:
diff --git a/szilagyi/tests.py b/szilagyi/tests.py
index bf59873..40d82f7 100644
--- a/szilagyi/tests.py
+++ b/szilagyi/tests.py
@@ -1,16 +1,22 @@
 import unittest
+import pint
 
 from . import calculate_swi
 
 
 class CalculateSwi(unittest.TestCase):
+	def setUp(self):
+		ureg = pint.UnitRegistry()
+		self.C = ureg.C
+		self.ft = ureg.ft
+
 	def test_out_of_range(self):
 		samples = [
-			(20, -10),
-			(-10, 25000),
-			(20, 60000),
-			(41, 25000),
-			(41, -10),
+			(20 * self.C, -10 * self.ft),
+			(-10 * self.C, 25000 * self.ft),
+			(20 * self.C, 60000 * self.ft),
+			(41 * self.C, 25000 * self.ft),
+			(41 * self.C, -10 * self.ft),
 		]
 		for dt, depth in samples:
 			with self.assertRaises(ValueError):
@@ -18,12 +24,12 @@ class CalculateSwi(unittest.TestCase):
 
 	def test_between(self):
 		samples = [
-			(6.53, 30000, 1, 2),
-			(10.78, 20500, -1, 0),
-			(24.45, 2600, 0, 1),
-			(7.22, 1300, -10, -9),
-			(16.1, 6200, 0, 1),
-			(3, 20000, -4, -3),
+			(6.53 * self.C, 30000 * self.ft, 1, 2),
+			(10.78 * self.C, 20500 * self.ft, -1, 0),
+			(24.45 * self.C, 2600 * self.ft, 0, 1),
+			(7.22 * self.C, 1300 * self.ft, -10, -9),
+			(16.1 * self.C, 6200 * self.ft, 0, 1),
+			(3 * self.C, 20000 * self.ft, -4, -3),
 		]
 		for dt, depth, low, high in samples:
 			swi = calculate_swi(dt, depth)