Improve Testing Coverage for Numba Caching (#1085)

* Added tests for numba and computing

* Added test cases

---------

Co-authored-by: Philip Chmielowiec <67855069+philipc2@users.noreply.github.com>
Co-authored-by: Philip Chmielowiec <philipchmielowiec@gmail.com>

test/test_utils.py

@@ -0,0 +1,88 @@
+import sys
+
+from uxarray.utils.numba import is_numba_function_cached
+from unittest import TestCase
+
+import unittest
+from unittest.mock import MagicMock, patch, mock_open
+import os
+import pickle
+import numba
+from uxarray.utils import computing
+import numpy as np
+
+
+class TestNumba(TestCase):
+    @patch("os.path.isfile")
+    @patch("builtins.open", new_callable=mock_open)
+    def test_numba_function_cached_valid_cache(self, mock_open_func, mock_isfile):
+        # Mock setup
+        mock_isfile.return_value = True
+        mock_open_func.return_value.__enter__.return_value.read = MagicMock(return_value=pickle.dumps(("stamp", None)))
+
+        mock_func = MagicMock()
+        mock_func._cache._cache_path = "/mock/cache/path"
+        mock_func._cache._cache_file._index_name = "mock_cache.pkl"
+        mock_func._cache._impl.locator.get_source_stamp.return_value = "stamp"
+
+        # Mock pickle version load
+        with patch("pickle.load", side_effect=[numba.__version__]):
+            result = is_numba_function_cached(mock_func)
+
+        self.assertTrue(result)
+
+    @patch("os.path.isfile")
+    @patch("builtins.open", new_callable=mock_open)
+    def test_numba_function_cached_invalid_cache_version(self, mock_open_func, mock_isfile):
+        # Mock setup
+        mock_isfile.return_value = True
+        mock_open_func.return_value.__enter__.return_value.read = MagicMock(return_value=pickle.dumps(("stamp", None)))
+
+        mock_func = MagicMock()
+        mock_func._cache._cache_path = "/mock/cache/path"
+        mock_func._cache._cache_file._index_name = "mock_cache.pkl"
+        mock_func._cache._impl.locator.get_source_stamp.return_value = "stamp"
+
+        # Mock pickle version load with mismatched version
+        with patch("pickle.load", side_effect=["invalid_version"]):
+            result = is_numba_function_cached(mock_func)
+
+        self.assertFalse(result)
+
+    @patch("os.path.isfile")
+    def test_numba_function_cached_no_cache_file(self, mock_isfile):
+        # Mock setup
+        mock_isfile.return_value = False
+
+        mock_func = MagicMock()
+        mock_func._cache._cache_path = "/mock/cache/path"
+        mock_func._cache._cache_file._index_name = "mock_cache.pkl"
+
+        result = is_numba_function_cached(mock_func)
+        self.assertFalse(result)
+
+    def test_numba_function_cached_no_cache_attribute(self):
+        mock_func = MagicMock()
+        del mock_func._cache  # Ensure _cache attribute does not exist
+
+        result = is_numba_function_cached(mock_func)
+        self.assertTrue(result)
+
+    @patch("os.path.isfile")
+    @patch("builtins.open", new_callable=mock_open)
+    def test_numba_function_cached_invalid_stamp(self, mock_open_func, mock_isfile):
+        # Mock setup
+        mock_isfile.return_value = True
+        mock_open_func.return_value.__enter__.return_value.read = MagicMock(
+            return_value=pickle.dumps(("invalid_stamp", None)))
+
+        mock_func = MagicMock()
+        mock_func._cache._cache_path = "/mock/cache/path"
+        mock_func._cache._cache_file._index_name = "mock_cache.pkl"
+        mock_func._cache._impl.locator.get_source_stamp.return_value = "stamp"
+
+        # Mock pickle version load
+        with patch("pickle.load", side_effect=[numba.__version__]):
+            result = is_numba_function_cached(mock_func)
+
+        self.assertFalse(result)