~ Use lazy bytestring

This lead to the following consequences:

  * we could efficiently read from storage - if block intersects files
    boundaries then we will "view" the block in the two different
    bytestrings. To avoid concat we now return lazy bytestring;

  * we could read block from socket without "concat" - again, for the
    same reason.

The pitfail is that now we have a bit more heap object, but blocks
lifetime is very short and this shouldnt play the big difference. The
lifetime is either (socket -> storage -> unreachable) or (storage ->
socket -> unreachable) unless a lib user keep block for their own
purposes.

1 files changed, 3 insertions, 0 deletions

diff --git a/tests/Main.hs b/tests/Main.hs
index b99f2469..45f92813 100644
--- a/tests/Main.hs
+++ b/tests/Main.hs
@@ -161,6 +161,9 @@ positive = fromIntegral <$> (arbitrary :: Gen Word32)
 instance Arbitrary ByteString where
   arbitrary = B.pack <$> arbitrary
 
+instance Arbitrary Lazy.ByteString where
+  arbitrary = Lazy.pack <$> arbitrary
+
 instance Arbitrary BlockIx where
   arbitrary = BlockIx <$> positive <*> positive <*> positive