Fix resolve python interpreter when frozen (#143)

Always use embedded Python as default when frozen and on Windows. We cannot search python from the PATH because %USERPROFILE%/AppData/Local/Microsoft/WindowsApps/ is in PATH by default on all users and this dir contains a python.exe that either opens the Microsoft Store or opens the Python that was downloaded from the Microsoft Store.

Fixes spine-tools/Spine-Toolbox#2823

spine_engine/config.py

@@ -10,11 +10,7 @@
 # this program. If not, see <http://www.gnu.org/licenses/>.
 ######################################################################################################################
 
-"""
-Application constants.
-
-"""
-
+"""Spine Engine constants."""
 import os
 import sys
 

spine_engine/utils/helpers.py

@@ -130,9 +130,10 @@ def resolve_current_python_interpreter():
     """
     if not is_frozen():
         return sys.executable
-    path = resolve_executable_from_path(PYTHON_EXECUTABLE)
-    if path != "":
-        return path
+    if not sys.platform == "win32":
+        path = resolve_executable_from_path(PYTHON_EXECUTABLE)
+        if path != "":
+            return path
     return EMBEDDED_PYTHON
 
 

tests/utils/test_helpers.py

@@ -10,16 +10,20 @@
 # this program. If not, see <http://www.gnu.org/licenses/>.
 ######################################################################################################################
 
-"""
-Unit tests for chunk module.
-
-"""
+"""Unit tests for chunk module."""
+import sys
 import unittest
-
+from unittest import mock
 from spine_engine.project_item.connection import Connection, FilterSettings
 from spinedb_api.filters.scenario_filter import SCENARIO_FILTER_TYPE
 from spinedb_api.helpers import remove_credentials_from_url
-from spine_engine.utils.helpers import make_dag, gather_leaf_data, get_file_size, required_items_for_execution
+from spine_engine.utils.helpers import (
+    make_dag,
+    gather_leaf_data,
+    get_file_size,
+    required_items_for_execution,
+    resolve_python_interpreter,
+)
 
 
 class TestRequiredItemsForExecution(unittest.TestCase):
@@ -188,5 +192,31 @@ def test_get_file_size(self):
         self.assertEqual(expected_output, output)
 
 
+class TestPythonInterpreter(unittest.TestCase):
+    def test_resolve_python_interpreter(self):
+        expected_path = "path_to_python"
+        settings = TestAppSettings(expected_path)
+        p = resolve_python_interpreter(settings)
+        self.assertEqual(expected_path, p)
+        settings = TestAppSettings("")
+        p = resolve_python_interpreter(settings)
+        self.assertEqual(sys.executable, p)
+        if sys.platform == "win32":
+            with mock.patch("spine_engine.utils.helpers.is_frozen") as mock_helpers_is_frozen:
+                mock_helpers_is_frozen.return_value = True
+                p = resolve_python_interpreter(settings)
+                self.assertIsNone(p)  # This is None only on Win. # FIXME: Find a way to mock is_frozen() in config.py
+                mock_helpers_is_frozen.assert_called()
+
+
+class TestAppSettings:
+    def __init__(self, test_path):
+        self.test_path = test_path
+
+    def value(self, key):
+        if key == "appSettings/pythonPath":
+            return self.test_path
+
+
 if __name__ == "__main__":
     unittest.main()