Merge rust-bitcoin/rust-bitcoin#1011: Add non_exhaustive compiler directive to AddressType

43b684b Add non_exhaustive compiler directive to AddressType (Tobin C. Harding)

Pull request description:

  Add non_exhaustive compiler directive to AddressType

  Currently adding variants to enums is a breaking change. In an effort to
  reduce the upgrade burden on users we can use the `non_exhaustive`
  compiler directive so that adding a new variant does not cause
  downstream code to break.

  Add `non_exhaustive` to the `AddressType` since it may be extended in
  the future.

ACKs for top commit:
  sanket1729:
    ACK 43b684b
  Kixunil:
    ACK 43b684b
  apoelstra:
    ACK 43b684b

Tree-SHA512: 2b2a15fb501d23058acca94318776ffcccedf463d43d07afa290fba46a7bd58b3a730f6e1f25605ef399afcfdb5de4c7ad67eaa0adff0ba39b0096cbcec10f57

Author: apoelstra

src/util/address.rs

@@ -140,6 +140,7 @@ impl From<bech32::Error> for Error {
 
 /// The different types of addresses.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[non_exhaustive]
 pub enum AddressType {
     /// Pay to pubkey hash.
     P2pkh,