Disallow applying patches when git tree is dirty

git_cl.py

Index: git_cl.py
diff --git a/git_cl.py b/git_cl.py
index 4edb6a0af8e1ee834f7f8305e92e435a3c1f9cee..46f1199ce1385c2df58c515d3ecb767a7a0dfdb1 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -2401,6 +2401,9 @@ def CMDpatch(parser, args):
     return 1
   issue_arg = args[0]
 
+  if is_dirty_git_tree('patch'):
+    return 1
+
   # TODO(maruel): Use apply_issue.py
   # TODO(ukai): use gerrit-cherry-pick for gerrit repository?
 
@@ -2464,6 +2467,7 @@ def PatchIssue(issue_arg, reject, nocommit, directory):
     subprocess2.check_call(cmd, env=GetNoGitPagerEnv(),
                            stdin=patch_data, stdout=subprocess2.VOID)
   except subprocess2.CalledProcessError:
+    RunGit(['reset', '--hard'])
     DieWithError('Failed to apply the patch')
 
   # If we had an issue, commit the current state and register the issue.
@@ -2769,6 +2773,9 @@ def CMDset_close(parser, args):
 
 def CMDdiff(parser, args):
   """shows differences between local tree and last upload."""
+  if is_dirty_git_tree('diff'):
+    return 1

[iannucci, 2015/02/02 15:49:42]

Hm... why is this necessary?

[wychen, 2015/02/02 17:09:25]

This is basically a safety measure. If the user have local uncommitted changes
(dirty tree), these changes might get destroyed by "reset --hard" if the
patching step has merging conflict.

I thought about automatically "git stash" first so the user don't have to do
anything due to this change. However, if the user has partially staged changes,
it could also be slightly harmful because the user has to do "add -p" again.

If some local uncommitted changes are staged, the behavior of "git cl diff"
would be unexpected (staged changes count towards last upload).

I should probably add some comments in the code to explain this.

+
   cl = Changelist()
   issue = cl.GetIssue()
   branch = cl.GetBranch()