bpo-30374: Fixed several bugs in win_add2path.py

Tools/scripts/win_add2path.py

@@ -7,47 +7,70 @@
 Licensed to PSF under a Contributor Agreement.
 """
 
-import sys
-import site
+import ctypes
 import os
+import site
+import sys
 import winreg
 
 HKCU = winreg.HKEY_CURRENT_USER
 ENV = "Environment"
 PATH = "PATH"
-DEFAULT = "%PATH%"
 
 def modify():
     pythonpath = os.path.dirname(os.path.normpath(sys.executable))
     scripts = os.path.join(pythonpath, "Scripts")
     appdata = os.environ["APPDATA"]
-    if hasattr(site, "USER_SITE"):
-        usersite = site.USER_SITE.replace(appdata, "%APPDATA%")
-        userpath = os.path.dirname(usersite)
-        userscripts = os.path.join(userpath, "Scripts")
-    else:
-        userscripts = None
 
     with winreg.CreateKey(HKCU, ENV) as key:
         try:
-            envpath = winreg.QueryValueEx(key, PATH)[0]
-        except OSError:
-            envpath = DEFAULT
+            envpath, dtype = winreg.QueryValueEx(key, PATH)
+        except FileNotFoundError:
+            envpath, dtype = "", winreg.REG_EXPAND_SZ
+        except:
+            raise OSError("Failed to load PATH value")
+
+        userscripts = None
+        if hasattr(site, "USER_SITE"):
+            if dtype == winreg.REG_EXPAND_SZ:
+                usersite = site.USER_SITE.replace(appdata, "%APPDATA%")
+                userpath = os.path.dirname(usersite)
+                userscripts = os.path.join(userpath, "Scripts")
+            elif dtype == winreg.REG_SZ:
+                userpath = site.USER_SITE
+                userscripts = os.path.join(userpath, "Scripts")
 
-        paths = [envpath]
+        paths = []
         for path in (pythonpath, scripts, userscripts):
-            if path and path not in envpath and os.path.isdir(path):
+            if path and path not in envpath:
                 paths.append(path)
 
-        envpath = os.pathsep.join(paths)
-        winreg.SetValueEx(key, PATH, 0, winreg.REG_EXPAND_SZ, envpath)
+        if envpath == "":
+            envpath = os.pathsep.join(paths)
+        else:
+            envpath = os.pathsep.join([envpath] + paths)
+        winreg.SetValueEx(key, PATH, 0, dtype, envpath)
         return paths, envpath
 
+def refresh_environment_variables():
+        HWND_BROADCAST = 0xFFFF
+        WM_SETTINGCHANGE = 0x001A
+        SMTO_ABORTIFHUNG = 0x0002
+        if not ctypes.windll.user32.SendMessageTimeoutW(
+                HWND_BROADCAST,
+                WM_SETTINGCHANGE,
+                0,
+                ENV,
+                SMTO_ABORTIFHUNG,
+                1000):
+            raise ctypes.WinError()
+
 def main():
     paths, envpath = modify()
     if len(paths) > 1:
+        refresh_environment_variables()
         print("Path(s) added:")
-        print('\n'.join(paths[1:]))
+        print('\n'.join(paths))
     else:
         print("No path was added")
     print("\nPATH is now:\n%s\n" % envpath)