Support for testnet wifs and addresses

[coinlogic]

Looks like encoding.py doesn't support testnet wifs and addresses. This is mainly because the allowable_prefixes are only limited to mainnet. Is there any specific reason for this limitation? Or can this limitation be removed to allow testnet?

[richardkiss]

You can set allowable_prefixes of is_valid_bitcoin_address to any list of prefixes... the idea is to look it up in pycoin.networks.address_prefix_for_netcode.

If this isn't clear, feel free to reopen this issue for clarification.

[coinlogic]

The problem is not limited to is_valid_bitcoin.

Look at is_valid_wif() there is no way to specify the prefix here. Or in wif_to_secret_exponent().
Testnet wifs have a different prefix, so these functions fail when used with testnet wifs. Further, these functions are used at several places with an assumption of mainnet wif prefixes. e.g. in scripts/spend.py and tx/tx_utils.py

[richardkiss]

Gotchya, I'll fix it.

[richardkiss]

Fixed in 9040e3b