This commit remove the error return from the Block.Sha function since it
can never fail and ends up causing a lot of unneeded error checking
throughout the code base.
This commit removes the previously deprecated TxShas function from
btcutil.Block. The preferred method to access transaction hashes is via
the Sha function on each btcutil.Tx contained within the block.
For example, the following illustrates how convert the old TxShas approach
to the new method:
OLD:
for i, sha := range block.TxShas() {
// use sha
}
NEW:
for i, tx := range block.Transactions() {
// use tx.Sha()
}
This commit also updates the tests for the removed function.
This commit adds both positive and negative tests for the new Tx and
Transactions Block API functions.
This is part of the ongoing transaction hash optimization effort noted in
conformal/btcd#25.
This commit unfortunately changes the public API of Block which I
ordinarily don't like to do, but in this case, I felt it was necessary.
The blocks used throughout the database and elsewhere should be indepedent
of the protocol version which is used to encode the block to wire format.
Each block has its own Version field which should be the deciding factor
for the serialization and deserialization of blocks. In practice, they
are currently the same encoding, but that may not always be the case, and
it's important the blocks are stable depending on their own version
regardless of the protocol version.
This makes use of the new Serialize and Deserialize functions on MsgBlock
which are intended for long-term storage as opposed to wire encoding.
