Never go back to evaluated=0httpchunking

1 files changed, 1 insertions, 1 deletions

diff --git a/src/ht.erl b/src/ht.erl
index 87090f0..80a0d29 100644
--- a/src/ht.erl
+++ b/src/ht.erl
@@ -335,7 +335,7 @@ update(Tree) ->
 %% @doc Calculate hashes in Tree up to and including node with index
 %% equal to Version. Update Tree.evaluated to reflect the new state.
 -spec update(tree(), non_neg_integer()) -> tree().
-update(Tree, 0) ->
+update(Tree = #tree{evaluated = E}, 0) when E == -1 ->
     %% A version 0 tree needs no updating.
     Tree#tree{evaluated = 0};
 update(Tree = #tree{evaluated = E}, V) when E >= V ->