mq: fix traceback for qpush inexistant-patch with no patch applied

hgext/mq.py

@@ -977,6 +977,8 b' class queue(object):'
                 self.ui.warn(_('done\n'))
                 raise
 
+            if not self.applied:
+                return ret[0]
             top = self.applied[-1].name
             if ret[0] and ret[0] > 1:
                 msg = _("errors during apply, please fix and refresh %s\n")

tests/test-mq-qpush-fail

@@ -53,4 +53,10 b' rm .hg/patches/patch2'
 echo '% now we expect the push to fail, but it should NOT complain about patch1'
 hg qpush
 
+echo '% preparing qpush of missing patch with no patch applied'
+hg qpop -a
+rm .hg/patches/patch1
+echo '% qpush should fail the same way as below'
+hg qpush
+
 true # happy ending

tests/test-mq-qpush-fail.out

@@ -27,3 +27,8 b' now at: patch1'
 applying patch2
 unable to read patch2
 now at: patch1
+% preparing qpush of missing patch with no patch applied
+patch queue now empty
+% qpush should fail the same way as below
+applying patch1
+unable to read patch1