Fix interpreter detection issues on windows

Non existing paths were added, empty interpreter should never happen, should be set to sys.executable

Author: ColinDuquesnoy

examples/pynotepad/pynotepad/settings.py

@@ -13,7 +13,10 @@ def __init__(self):
 
     @property
     def interpreter(self):
-        return self.settings.value('interpreter', '')
+        interpreter = self.settings.value('interpreter', '')
+        if not os.path.exists(interpreter):
+            interpreter = ''
+        return interpreter
 
     @interpreter.setter
     def interpreter(self, value):

examples/pynotepad/pynotepad/utils.py

@@ -15,6 +15,8 @@ def get_interpreters():
         for path in paths:
             if 'python' in path.lower():
                 if 'scripts' in path.lower():
-                     path = os.path.abspath(os.path.join(path, os.pardir))
-                executables.add(os.path.join(path, 'python.exe'))
+                    path = os.path.abspath(os.path.join(path, os.pardir))
+            executable = os.path.join(path, 'python.exe')
+            if os.path.exists(executable):
+                executables.add(executable)
     return executables