Patch #957650: "%var%" environment variable references are now properly

expanded in ntpath.expandvars(), also "~user" home directory references
are recognized and handled on Windows.

Lib/ntpath.py

@@ -278,36 +278,44 @@ def expanduser(path):
     i, n = 1, len(path)
     while i < n and path[i] not in '/\\':
         i = i + 1
-    if i == 1:
-        if 'HOME' in os.environ:
-            userhome = os.environ['HOME']
-        elif not 'HOMEPATH' in os.environ:
-            return path
-        else:
-            try:
-                drive = os.environ['HOMEDRIVE']
-            except KeyError:
-                drive = ''
-            userhome = join(drive, os.environ['HOMEPATH'])
-    else:
+
+    if 'HOME' in os.environ:
+        userhome = os.environ['HOME']
+    elif 'USERPROFILE' in os.environ:
+        userhome = os.environ['USERPROFILE']
+    elif not 'HOMEPATH' in os.environ:
         return path
+    else:
+        try:
+            drive = os.environ['HOMEDRIVE']
+        except KeyError:
+            drive = ''
+        userhome = join(drive, os.environ['HOMEPATH'])
+
+    if i != 1: #~user
+        userhome = join(dirname(userhome), path[1:i])
+
     return userhome + path[i:]
 
 
 # Expand paths containing shell variable substitutions.
 # The following rules apply:
 #       - no expansion within single quotes
-#       - no escape character, except for '$$' which is translated into '$'
+#       - '$$' is translated into '$'
+#       - '%%' is translated into '%' if '%%' are not seen in %var1%%var2%
 #       - ${varname} is accepted.
-#       - varnames can be made out of letters, digits and the character '_'
+#       - $varname is accepted.
+#       - %varname% is accepted.
+#       - varnames can be made out of letters, digits and the characters '_-'
+#         (though is not verifed in the ${varname} and %varname% cases)
 # XXX With COMMAND.COM you can use any characters in a variable name,
 # XXX except '^|<>='.
 
 def expandvars(path):
-    """Expand shell variables of form $var and ${var}.
+    """Expand shell variables of the forms $var, ${var} and %var%.
 
     Unknown variables are left unchanged."""
-    if '$' not in path:
+    if '$' not in path and '%' not in path:
         return path
     import string
     varchars = string.ascii_letters + string.digits + '_-'
@@ -325,6 +333,24 @@ def expandvars(path):
             except ValueError:
                 res = res + path
                 index = pathlen - 1
+        elif c == '%':  # variable or '%'
+            if path[index + 1:index + 2] == '%':
+                res = res + c
+                index = index + 1
+            else:
+                path = path[index+1:]
+                pathlen = len(path)
+                try:
+                    index = path.index('%')
+                except ValueError:
+                    res = res + '%' + path
+                    index = pathlen - 1
+                else:
+                    var = path[:index]
+                    if var in os.environ:
+                        res = res + os.environ[var]
+                    else:
+                        res = res + '%' + var + '%'
         elif c == '$':  # variable or '$$'
             if path[index + 1:index + 2] == '$':
                 res = res + c