Make svndiff.py work on Windows and with svn 1.7.

tools/svndiff.py

Index: tools/svndiff.py
===================================================================
--- tools/svndiff.py	(revision 11593)
+++ tools/svndiff.py	(working copy)
@@ -223,7 +223,12 @@
     dest_dir = os.path.abspath(dest_dir)
 
     os.chdir(source_dir)
-    using_svn = os.path.isdir('.svn')
+    svn_repo = svn.Svn('.')
+    using_svn = True
+    try:
+      svn_repo.GetInfo()
+    except:
+      using_svn = False
 
     # Prepare temporary directories.
     modified_flattened_dir = os.path.join(dest_dir, 'modified_flattened')
@@ -236,7 +241,6 @@
     # Get a list of all locally modified (including added/deleted) files,
     # descending subdirectories.
     if using_svn:
-        svn_repo = svn.Svn('.')
         modified_file_paths = svn_repo.GetFilesWithStatus(
             svn.STATUS_ADDED | svn.STATUS_DELETED | svn.STATUS_MODIFIED)
     else:
@@ -249,23 +253,26 @@
         if modified_file_path.endswith('.json'):
             # Special handling for JSON files, in the hopes that they
             # contain GM result summaries.
-            (_unused, original_file_path) = tempfile.mkstemp()
+            original_file = tempfile.NamedTemporaryFile(delete = False)
+            original_file.close()
             if using_svn:
                 svn_repo.ExportBaseVersionOfFile(
-                    modified_file_path, original_file_path)
+                    modified_file_path, original_file.name)
             else:
                 _GitExportBaseVersionOfFile(
-                    modified_file_path, original_file_path)
-            platform_prefix = re.sub(os.sep, '__',
-                                     os.path.dirname(modified_file_path)) + '__'
-            _CallJsonDiff(old_json_path=original_file_path,
+                    modified_file_path, original_file.name)
+            original_directory = os.path.dirname(original_file.name)
+            platform_prefix = (re.sub(re.escape(os.sep), '__',
+                                      os.path.splitdrive(original_directory)[1])
+                              + '__')
+            _CallJsonDiff(old_json_path=original_file.name,
                           new_json_path=modified_file_path,
                           old_flattened_dir=original_flattened_dir,
                           new_flattened_dir=modified_flattened_dir,
                           filename_prefix=platform_prefix)
-            os.remove(original_file_path)
+            os.remove(original_file.name)
         else:
-            dest_filename = re.sub(os.sep, '__', modified_file_path)
+            dest_filename = re.sub(re.escape(os.sep), '__', modified_file_path)
             # If the file had STATUS_DELETED, it won't exist anymore...
             if os.path.isfile(modified_file_path):
                 shutil.copyfile(modified_file_path,
@@ -283,6 +290,7 @@
     # Run skdiff: compare original_flattened_dir against modified_flattened_dir
     RunCommand('%s %s %s %s' % (path_to_skdiff, original_flattened_dir,
                                 modified_flattened_dir, diff_dir))
+
     print '\nskdiff results are ready in file://%s/index.html' % diff_dir
 
 def RaiseUsageException():