--- a/tests/test-rebase-scenario-global.t Fri Jan 31 14:52:53 2014 -0800
+++ b/tests/test-rebase-scenario-global.t Fri Jan 31 15:13:15 2014 -0800
@@ -649,3 +649,28 @@
|/
o 0: 'A'
+
+Test that rebase is not confused by $CWD disapearing during rebase (issue 4121)
+
+ $ cd ..
+ $ hg init cwd-vanish
+ $ cd cwd-vanish
+ $ touch initial-file
+ $ hg add initial-file
+ $ hg commit -m 'initial commit'
+ $ touch dest-file
+ $ hg add dest-file
+ $ hg commit -m 'dest commit'
+ $ hg up 0
+ 0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+ $ touch other-file
+ $ hg add other-file
+ $ hg commit -m 'first source commit'
+ created new head
+ $ mkdir subdir
+ $ cd subdir
+ $ touch subfile
+ $ hg add subfile
+ $ hg commit -m 'second source with subdir'
+ $ hg rebase -b . -d 1 --traceback
+ saved backup bundle to $TESTTMP/cwd-vanish/.hg/strip-backup/779a07b1b7a0-backup.hg (glob)