feat: add Nano address validation and Chain::Nano

Cargo.toml

@@ -149,14 +149,14 @@ serde_json = "1"
 # the library itself still compile with the gates off.
 [[example]]
 name = "basic"
-required-features = ["btc", "evm", "solana", "tron", "keccak"]
+required-features = ["btc", "evm", "solana", "tron", "nano", "keccak"]
 
 [[test]]
 name = "public_api"
 required-features = ["btc", "evm", "solana", "tron", "keccak"]
 
 [features]
-default = ["btc", "evm", "solana", "tron", "keccak", "net", "key", "asset", "client", "tx", "x402", "wire", "eip712", "abi"]
+default = ["btc", "evm", "solana", "tron", "nano", "keccak", "net", "key", "asset", "client", "tx", "x402", "wire", "eip712", "abi"]
 # Every gate below that names a module this crate no longer owns forwards to the
 # crate that does. The names are unchanged on purpose: a consumer that asked for
 # `tinywallet/btc` before the split gets exactly what it got before, from a
@@ -172,6 +172,8 @@ evm = ["tinywallet-crypto/evm"]
 solana = ["tinywallet-crypto/solana"]
 # Tron base58check address validation and hex conversion.
 tron = ["tinywallet-crypto/tron"]
+# Nano address validation and encoding.
+nano = ["tinywallet-crypto/nano"]
 # EIP-55 mixed-case checksum support for EVM addresses. `dep:sha3` is this
 # crate's own, for the addresses `key` derivation produces.
 keccak = ["evm", "dep:sha3", "tinywallet-crypto/keccak"]

README.md

@@ -4,8 +4,8 @@ Agent-friendly multi-chain wallet primitives in Rust.
 
 `tinywallet` owns the parts of wallet handling that are pure: address formats,
 their validation, and the conversions between their encodings. Bitcoin, EVM
-chains, Solana, and Tron each get a module, and `address::validate` dispatches
-across them for chain-generic callers.
+chains, Solana, Tron, and Nano each get a module, and `address::validate`
+dispatches across them for chain-generic callers.
 
 ```rust
 use tinywallet::{address, Chain};
@@ -40,6 +40,7 @@ because it is easy to assume otherwise:
 | --- | --- | --- |
 | Bitcoin | yes (base58check / bech32) | caught |
 | Tron | yes (base58check) | caught |
+| Nano | yes (blake2b, 40 bits) | caught |
 | EVM | optional (EIP-55, only if mixed-case) | usually **not** caught |
 | Solana | none | **not reliably** caught |
 
@@ -75,6 +76,7 @@ not pay for the others' parsers.
 | `evm` | on | EVM addresses | — (dependency-free) |
 | `solana` | on | Solana addresses | `bs58` |
 | `tron` | on | Tron addresses | `bs58`, `hex` |
+| `nano` | on | Nano addresses (`nano_` / legacy `xrb_`) | `blake2` |
 | `keccak` | on | EIP-55 checksums for EVM | `sha3` |
 
 With a chain's gate off, `address::validate` returns `Error::ChainNotCompiled`
@@ -170,7 +172,7 @@ must error, never validate):
 ```sh
 cargo clippy --all-targets --no-default-features -- -D warnings
 cargo test --lib --no-default-features
-for f in btc evm solana tron keccak; do
+for f in btc evm solana tron nano keccak; do
   cargo check --lib --no-default-features --features "$f"
   cargo test --lib --no-default-features --features "$f"
 done

crates/tinywallet-bus/src/chain/mod.rs

@@ -38,17 +38,19 @@ pub enum Chain {
     Solana,
     /// Tron (mainnet).
     Tron,
+    /// Nano (mainnet).
+    Nano,
 }
 
 impl Chain {
     /// Every chain this crate knows, in declaration order.
     ///
     /// Useful for a host enumerating supported chains. This is the full set
     /// regardless of which feature gates are enabled — see the module docs.
-    pub const ALL: &'static [Self] = &[Self::Btc, Self::Evm, Self::Solana, Self::Tron];
+    pub const ALL: &'static [Self] = &[Self::Btc, Self::Evm, Self::Solana, Self::Tron, Self::Nano];
 
     /// The chain's lowercase machine-readable name (`"btc"`, `"evm"`,
-    /// `"solana"`, `"tron"`).
+    /// `"solana"`, `"tron"`, `"nano"`).
     ///
     /// This is the form [`Chain::from_str`] parses, so `chain.as_str()` always
     /// round-trips.
@@ -59,6 +61,7 @@ impl Chain {
             Self::Evm => "evm",
             Self::Solana => "solana",
             Self::Tron => "tron",
+            Self::Nano => "nano",
         }
     }
 }
@@ -95,6 +98,7 @@ impl FromStr for Chain {
             "evm" | "eth" | "ethereum" => Ok(Self::Evm),
             "solana" | "sol" => Ok(Self::Solana),
             "tron" | "trx" => Ok(Self::Tron),
+            "nano" | "xno" => Ok(Self::Nano),
             other => Err(UnknownChain(other.to_string())),
         }
     }

crates/tinywallet-bus/src/chain/mod_tests.rs

@@ -55,3 +55,16 @@ fn an_unknown_name_is_reported_with_the_input() {
         UnknownChain("dogecoin".to_string())
     );
 }
+
+#[test]
+fn nano_parses_with_its_aliases() {
+    for input in ["nano", "xno", "NANO"] {
+        assert_eq!(
+            Chain::from_str(input).unwrap(),
+            Chain::Nano,
+            "alias {input}"
+        );
+    }
+    assert_eq!(Chain::Nano.as_str(), "nano");
+    assert!(Chain::ALL.contains(&Chain::Nano));
+}

crates/tinywallet-crypto/Cargo.toml

@@ -33,6 +33,8 @@ hex = { version = "0.4", optional = true }
 bech32 = { version = "0.12", optional = true }
 # SHA-256: Bitcoin's HASH160, Tron's base58check checksum, and the Tron txid.
 sha2 = { version = "0.11", optional = true }
+# Blake2b-40, the checksum on a Nano address; see `src/address/nano.rs`.
+blake2 = { version = "0.11", default-features = false, optional = true }
 # Keccak-256 for EIP-55 checksums on EVM addresses.
 #
 # Pinned to 0.12. The root crate's `coins-bip32` still depends on `sha3` 0.10,
@@ -57,7 +59,7 @@ serde_json = "1"
 
 [features]
 # Every feature the bus exposed before the split, so `default` matches it.
-default = ["btc", "evm", "solana", "tron", "keccak", "net", "asset", "tx-codec"]
+default = ["btc", "evm", "solana", "tron", "nano", "keccak", "net", "asset", "tx-codec"]
 # Bitcoin address parsing and validation. Dependency-light on purpose: base58
 # via `bs58` (already here for Solana and Tron) and segwit via `bech32`.
 btc = ["dep:bs58", "dep:bech32", "dep:sha2"]
@@ -72,6 +74,8 @@ evm = []
 solana = ["dep:bs58"]
 # Tron base58check address validation and hex conversion.
 tron = ["dep:bs58", "dep:hex"]
+# Nano address validation and encoding.
+nano = ["dep:blake2"]
 # EIP-55 mixed-case checksum support for EVM addresses.
 keccak = ["evm", "dep:sha3"]
 # The `Transport` network seam (`tinywallet_crypto::rpc`). The one module that

crates/tinywallet-crypto/src/address/mod.rs

@@ -3,7 +3,7 @@
 //! Each submodule owns one chain's address format and exposes the same core
 //! shape: a `validate` returning the trimmed address, plus whatever
 //! chain-specific conversions are genuinely useful (`solana::decode`,
-//! `tron::to_hex`, `btc::validate_sender`).
+//! `tron::to_hex`, `btc::validate_sender`, `nano::decode`).
 //!
 //! [`validate`] dispatches across all of them for chain-generic callers.
 //!
@@ -20,6 +20,7 @@
 //! | --- | --- | --- |
 //! | Bitcoin | yes (base58check / bech32) | caught |
 //! | Tron | yes (base58check) | caught |
+//! | Nano | yes (blake2b, 40 bits) | caught |
 //! | EVM | optional (EIP-55, only if mixed-case) | usually *not* caught |
 //! | Solana | none | *not reliably* caught |
 //!
@@ -34,6 +35,8 @@ use crate::chain::Chain;
 pub mod btc;
 #[cfg(feature = "evm")]
 pub mod evm;
+#[cfg(feature = "nano")]
+pub mod nano;
 #[cfg(feature = "solana")]
 pub mod solana;
 #[cfg(feature = "tron")]
@@ -72,7 +75,13 @@ pub mod tron;
 // `address` goes unread. That build is legal (a host may depend on this crate
 // purely for `Chain`), so the unused binding is expected rather than a bug.
 #[cfg_attr(
-    not(any(feature = "btc", feature = "evm", feature = "solana", feature = "tron")),
+    not(any(
+        feature = "btc",
+        feature = "evm",
+        feature = "solana",
+        feature = "tron",
+        feature = "nano"
+    )),
     allow(unused_variables)
 )]
 pub fn validate(chain: Chain, address: &str) -> Result<String> {
@@ -85,6 +94,8 @@ pub fn validate(chain: Chain, address: &str) -> Result<String> {
         Chain::Solana => Some(solana::validate),
         #[cfg(feature = "tron")]
         Chain::Tron => Some(tron::validate),
+        #[cfg(feature = "nano")]
+        Chain::Nano => Some(nano::validate),
         _ => None,
     };
     let validator = validator.ok_or(crate::Error::ChainNotCompiled { chain })?;

crates/tinywallet-crypto/src/address/mod_tests.rs

@@ -6,11 +6,15 @@ use super::validate;
 use crate::{Chain, Error};
 
 /// One valid mainnet address per chain.
-const FIXTURES: [(Chain, &str); 4] = [
+const FIXTURES: [(Chain, &str); 5] = [
     (Chain::Btc, "bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4"),
     (Chain::Evm, "0x52908400098527886E0F7030069857D2E4169EE7"),
     (Chain::Solana, "11111111111111111111111111111111"),
     (Chain::Tron, "TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t"),
+    (
+        Chain::Nano,
+        "nano_3t6k35gi95xu6tergt6p69ck76ogmitsa8mnijtpxm9fkcm736xtoncuohr3",
+    ),
 ];
 
 /// Whether the feature gate behind `chain` is on in this build.
@@ -28,6 +32,8 @@ const fn chain_enabled(chain: Chain) -> bool {
         Chain::Solana => true,
         #[cfg(feature = "tron")]
         Chain::Tron => true,
+        #[cfg(feature = "nano")]
+        Chain::Nano => true,
         _ => false,
     }
 }