convert/svn: make sink recover gracefully from empty changeset
Otherwise when processing a changeset that in fact changes no files
(perhaps due to bug in import from CVS) can get something like:
unexpected svn output:
abort: unable to cope with svn output
Bug report and patch draft by Jesse Glick <jesse.glick@sun.com>
adding a
% qnew should refuse bad patch names
abort: "series" cannot be used as the name of a patch
abort: "status" cannot be used as the name of a patch
abort: "guards" cannot be used as the name of a patch
abort: ".hgignore" cannot be used as the name of a patch
% qnew with uncommitted changes
abort: local changes found, refresh first
A somefile
% qnew implies add
A .hgignore
A series
A test.patch
% qnew missing
abort: missing: No such file or directory
% qnew -m
foo bar
% qnew twice
abort: patch "first.patch" already exists
abort: patch "first.patch" already exists
% qnew -f from a subdirectory
popping first.patch
popping mtest.patch
popping test.patch
patch queue now empty
adding d/b
M d/b
diff --git a/d/b b/d/b
--- a/d/b
+++ b/d/b
@@ -1,1 +1,2 @@
b
+b
% qnew -u with no username configured
From: blue