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
echo 123 > a
hg add a
hg commit -m "first" -d "1000000 0" a
mkdir sub
echo 321 > sub/b
hg add sub/b
hg commit -m "second" -d "1000000 0" sub/b
cat sub/b
hg co 0
cat sub/b 2>/dev/null || echo "sub/b not present"
test -d sub || echo "sub not present"

true