add dirstate._dirtypl variable Theoretically, it's possible to forget modified dirstate parents by doing: dirstate.invalidate() dirstate.setparents(p1, p2) dirstate._map The final access to _map should call _read(), which will unconditionally overwrite dirstate._pl. This doesn't actually happen right now because invalidate accidentally ends up rebuilding dirstate._map.

#!/bin/sh

hg init
touch unknown

touch a
hg add a
hg ci -m "1" -d "1000000 0"

touch b
hg add b
hg ci -m "2" -d "1000000 0"

echo %% Should show unknown
hg status
hg revert -r 0 --all
echo %% Should show unknown and b removed
hg status
echo %% Should show a and unknown
ls