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Co-authored-by: Daira-Emma Hopwood <[email protected]>

components/zcash_address/src/encoding.rs

@@ -90,6 +90,7 @@ impl FromStr for ZcashAddress {
                     let net = match hrp.as_str() {
                         tex::MAINNET => Network::Main,
                         tex::TESTNET => Network::Test,
+                        tex::REGTEST => Network::Regtest,
                         // Not recognized as a Zcash address type
                         _ => {
                             return Err(ParseError::NotZcash);
@@ -179,7 +180,8 @@ impl fmt::Display for ZcashAddress {
             AddressKind::Tex(data) => encode_bech32(
                 match self.net {
                     Network::Main => tex::MAINNET,
-                    Network::Test | Network::Regtest => tex::TESTNET,
+                    Network::Test => tex::TESTNET,
+                    Network::Regtest => tex::REGTEST,
                 },
                 data,
                 Variant::Bech32m,

components/zcash_address/src/kind/tex.rs

@@ -1,7 +1,11 @@
-/// The prefix for a Base58Check-encoded mainnet transparent
+/// The prefix for a Bech32m-encoded mainnet transparent
 /// [ZIP 320](https://zips.z.cash/zip-0320.html) TEX address.
 pub(crate) const MAINNET: &str = "tex";
 
-/// The prefix for a Base58Check-encoded testnet transparent
+/// The prefix for a Bech32m-encoded testnet transparent
 /// [ZIP 320](https://zips.z.cash/zip-0320.html) TEX address.
 pub(crate) const TESTNET: &str = "textest";
+
+/// The prefix for a Bech32m-encoded regtest transparent
+/// [ZIP 320](https://zips.z.cash/zip-0320.html) TEX address.
+pub(crate) const REGTEST: &str = "texregtest";

components/zcash_address/src/kind/unified.rs

@@ -505,6 +505,9 @@ pub(crate) mod private {
                         length
                     )));
                 }
+                // The "as usize" casts cannot change the values, because both
+                // cursor.position() and addr_end are u64 values <= buf.len()
+                // which is usize.
                 let data = &buf[cursor.position() as usize..addr_end as usize];
                 let result = match Typecode::try_from(typecode)? {
                     Typecode::Data(tc) => Item::Data(R::parse(tc, data)?),