clippy: introduce nightly-version and fix all clippy issues with it

Copy nightly-version from rust-elements. The next commit will use it in
Github CI. I won't bother making a cronjob for it because this crate is
so unused that it doesn't seem worthwhile opening constant PRs for CI
updates. We will try to do this manually every several months, or add
a cronjob if/when this becomes used.

I added an #[allow(unused)] tag on the elementsd test crate. Maybe this
trait is actually unused and should be deleted. But the elementsd tests
are old and bitrotted and I'd prefer to avoid touching them for purposes
of this PR.

This commit also introduces a lockfile. Basically, from this commit
onward I want my local CI to pass, so I am throwing in several things
at once.

Author: apoelstra

Cargo-latest.lock

@@ -9,6 +9,7 @@ keywords = [ "crypto", "bitcoin", "miniscript", "script" ]
 readme = "README.md"
 homepage = "https://github.com/rust-bitcoin/rust-miniscript/"
 edition = "2018"
+rust-version = "1.63.0"
 
 [features]
 compiler = []
@@ -61,3 +62,6 @@ required-features = ["base64"]
 
 [workspace]
 members = ["bitcoind-tests", "fuzz"]
+
+[lints.rust]
+unexpected_cfgs = { level = "deny", check-cfg = ['cfg(miniscript_bench)'] }

Cargo.toml

@@ -60,6 +60,7 @@ pub fn setup(validate_pegin: bool) -> (ElementsD, Option<BitcoinD>, elements::Bl
     (elementsd, bitcoind, genesis_hash)
 }
 // Upstream all common methods later
+#[allow(unused)]
 pub trait Call {
     fn call(&self, cmd: &str, args: &[Value]) -> Value;
     fn get_new_address(&self) -> elements::Address;

bitcoind-tests/tests/setup/mod.rs

@@ -322,7 +322,7 @@ fn find_sks_ms<Ctx: ScriptContext>(
         .iter_pk()
         .filter_map(|pk| {
             let i = pks.iter().position(|&x| x.to_public_key() == pk);
-            i.map(|idx| (sks[idx]))
+            i.map(|idx| sks[idx])
         })
         .collect();
     sks

bitcoind-tests/tests/test_desc.rs

@@ -1 +1,3 @@
 msrv = "1.63.0"
+# PSBT API returns Self as an error type for an large-ish enum
+large-error-threshold = 289

clippy.toml

@@ -0,0 +1 @@
+nightly-2025-08-19

nightly-version

@@ -969,7 +969,7 @@ impl<K: InnerXKey> DescriptorXKey<K> {
         if &compare_fingerprint == fingerprint
             && compare_path
                 .into_iter()
-                .eq(path_excluding_wildcard.into_iter())
+                .eq(&path_excluding_wildcard)
         {
             Some(path_excluding_wildcard)
         } else {

src/descriptor/key.rs

@@ -69,7 +69,7 @@ impl Pegin<DescriptorPublicKey> {
         secp: &secp256k1_zkp::Secp256k1<C>,
     ) -> Result<Pegin<PublicKey>, Error> {
         let elem_desc = self.elem_desc.at_derivation_index(arg)?;
-        let elem_desc = elem_desc.derived_descriptor(&secp)?;
+        let elem_desc = elem_desc.derived_descriptor(secp)?;
         Ok(Pegin::new(self.fed_desc.clone(), elem_desc))
     }
 }
@@ -172,7 +172,7 @@ impl<Pk: MiniscriptKey> Pegin<Pk> {
                     .expect("DO this cleanly after TR. Pay to taproot pegins unspecified till now"),
                 network,
             )),
-            _ => return Err(Error::UnsupportedAddressForPegin),
+            _ => Err(Error::UnsupportedAddressForPegin),
         }
     }
 

src/descriptor/pegin/dynafed_pegin.rs

@@ -16,9 +16,7 @@ use crate::{error, Extension, Miniscript, MiniscriptKey, ScriptContext, Terminal
 ///
 /// This allows parsing miniscripts if
 /// 1. It is unsafe(does not require a digital signature to spend it)
-/// 2. It contains a unspendable path because of either
-///     a. Resource limitations
-///     b. Timelock Mixing
+/// 2. It contains a unspendable path because of either resource limitations or timelock mixing.
 /// 3. The script is malleable and thereby some of satisfaction weight
 ///    guarantees are not satisfied.
 /// 4. It has repeated public keys
@@ -123,9 +121,7 @@ impl ExtParams {
 
 /// We currently mark Miniscript as Non-Analyzable if
 /// 1. It is unsafe(does not require a digital signature to spend it)
-/// 2. It contains a unspendable path because of either
-///     a. Resource limitations
-///     b. Timelock Mixing
+/// 2. It contains a unspendable path because of either resource limitations or timelock mixing.
 /// 3. The script is malleable and thereby some of satisfaction weight
 ///    guarantees are not satisfied.
 /// 4. It has repeated publickeys

src/miniscript/analyzable.rs

@@ -67,7 +67,7 @@ impl<Pk: MiniscriptKey, Ctx: ScriptContext, Ext: Extension> PartialOrd
     for Miniscript<Pk, Ctx, Ext>
 {
     fn partial_cmp(&self, other: &Miniscript<Pk, Ctx, Ext>) -> Option<cmp::Ordering> {
-        Some(self.node.cmp(&other.node))
+        Some(self.cmp(other))
     }
 }