Fix ManifestProject.partial_clone_exclude property.

Bug: b/256358360

Change-Id: Ic6e3a049aa38827123d0324c8b14157562c5986e
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/353574
Reviewed-by: Mike Frysinger <vapier@google.com>
Tested-by: Joanna Wang <jojwang@google.com>
Reviewed-by: Josip Sokcevic <sokcevic@google.com>

git_config.py

@@ -22,6 +22,7 @@ import re
 import ssl
 import subprocess
 import sys
+from typing import Union
 import urllib.error
 import urllib.request
 
@@ -117,7 +118,7 @@ class GitConfig(object):
       return self.defaults.Has(name, include_defaults=True)
     return False
 
-  def GetInt(self, name):
+  def GetInt(self, name: str) -> Union[int, None]:
     """Returns an integer from the configuration file.
 
     This follows the git config syntax.
@@ -126,7 +127,7 @@ class GitConfig(object):
       name: The key to lookup.
 
     Returns:
-      None if the value was not defined, or is not a boolean.
+      None if the value was not defined, or is not an int.
       Otherwise, the number itself.
     """
     v = self.GetString(name)
@@ -152,6 +153,9 @@ class GitConfig(object):
     try:
       return int(v, base=base) * mult
     except ValueError:
+      print(
+          f"warning: expected {name} to represent an integer, got {v} instead",
+          file=sys.stderr)
       return None
 
   def DumpConfigDict(self):
@@ -169,7 +173,7 @@ class GitConfig(object):
       config_dict[key] = self.GetString(key)
     return config_dict
 
-  def GetBoolean(self, name):
+  def GetBoolean(self, name: str) -> Union[str, None]:
     """Returns a boolean from the configuration file.
        None : The value was not defined, or is not a boolean.
        True : The value was set to true or yes.
@@ -183,6 +187,8 @@ class GitConfig(object):
       return True
     if v in ('false', 'no'):
       return False
+    print(f"warning: expected {name} to represent a boolean, got {v} instead",
+            file=sys.stderr)
     return None
 
   def SetBoolean(self, name, value):
@@ -191,7 +197,7 @@ class GitConfig(object):
       value = 'true' if value else 'false'
     self.SetString(name, value)
 
-  def GetString(self, name, all_keys=False):
+  def GetString(self, name: str, all_keys: bool = False) -> Union[str,  None]:
     """Get the first value for a key, or None if it is not defined.
 
        This configuration file is used first, if the key is not