Get test_opcode to run

src/logic/block_ops.nim

@@ -1,5 +1,5 @@
 import
-  ../constants, ../errors, ../computation, ../vm_state, ../types, .. / vm / [stack]
+  ../constants, ../errors, ../computation, ../vm_state, ../types, .. / vm / [stack], ttmath
 
 {.this: computation.}
 {.experimental.}
@@ -16,7 +16,7 @@ proc coinbase*(computation) =
   stack.push(vmState.coinbase)
 
 proc timestamp*(computation) =
-  stack.push(vmState.timestamp.u256)
+  stack.push(vmState.timestamp.uint64.u256) # TODO: EthTime (from Time) is distinct
 
 proc number*(computation) =
   stack.push(vmState.blockNumber)

src/utils/keccak.nim

@@ -1,10 +1,18 @@
 import
-  keccak_tiny, strutils
+  nimcrypto, strutils
 
+#[
 template keccak*(value: string): string =
   $keccak_256(value)
 
 template keccak*(value: cstring): string =
   ($value).keccak
+]#
 
+proc keccak*(value: string): string =
+  # TODO: Urgent - check this is doing the same thing as above
+  var k = sha3_256()
+  k.init
+  k.update(cast[ptr uint8](value[0].unsafeaddr), value.len.uint)
+  result = $finish(k)