chore: bump MSRV to 1.92.0 + adapt to clippy 1.92 pedantic strictness

Required for the next-generation storage backends (rocksdb 0.49 needs 1.89,
fjall 3.1 needs 1.90, redb 4.1 needs 1.89, signet-libmdbx 0.8 needs 1.92).
Picking 1.92 unlocks all four under one toolchain.

Adapted to clippy 1.92:
- Hand-fixed: needless_continue in mempool::pool::remove_index (loop tail);
  format_push_string in storage backend_equivalence (switched to fmt::Write::write!);
  manual const-fn additions across coinstats, pruning, p2p, utxo, etc. via
  'cargo clippy --fix'.
- Workspace-allowed: format_push_string, manual_let_else, missing_const_for_fn,
  collapsible_if, needless_continue, iter_without_into_iter,
  into_iter_without_iter (all new pedantic lints; style preferences not
  correctness gates).

CI's portable job still pins 1.92; the kernel-mdbx job's elevated toolchain
is no longer separate from MSRV and can fold into the main matrix.

Op: extend

Author: bitcoin-rs

Cargo.toml

@@ -24,7 +24,7 @@ members = [
 
 [workspace.package]
 edition      = "2024"
-rust-version = "1.85.0"
+rust-version = "1.92.0"
 license      = "MIT OR Apache-2.0"
 repository   = "https://github.com/bitcoin-rs/bitcoin-rs"
 version      = "0.1.0"
@@ -273,6 +273,15 @@ struct_field_names         = "allow"
 option_if_let_else          = "allow"
 significant_drop_tightening = "allow"
 redundant_pub_crate         = "allow"
+# Clippy 1.92 added pedantic lints that fire on patterns previously clippy-clean.
+# These are style preferences, not correctness gates; allow at the workspace level.
+manual_let_else            = "allow"
+format_push_string         = "allow"
+missing_const_for_fn       = "allow"
+collapsible_if             = "allow"
+needless_continue          = "allow"
+iter_without_into_iter     = "allow"
+into_iter_without_iter     = "allow"
 
 # ============================================================================
 # Profiles

clippy.toml

@@ -1,4 +1,4 @@
-msrv = "1.85.0"
+msrv = "1.92.0"
 cognitive-complexity-threshold = 15
 type-complexity-threshold = 250
 too-many-arguments-threshold = 8

crates/chain/src/tree.rs

@@ -181,10 +181,10 @@ impl BlockTree {
             return Ok(());
         }
 
-        if let Some(old_tip) = self.tip.load_full() {
-            if old_tip.tip_id != node_id {
-                self.node_mut(old_tip.tip_id)?.status = NodeStatus::Stale;
-            }
+        if let Some(old_tip) = self.tip.load_full()
+            && old_tip.tip_id != node_id
+        {
+            self.node_mut(old_tip.tip_id)?.status = NodeStatus::Stale;
         }
         self.node_mut(node_id)?.status = NodeStatus::Active;
         let node = self.node(node_id)?;

crates/coinstats/src/muhash3072.rs

@@ -147,7 +147,7 @@ fn chacha20_block(key: &[u8; 32], counter: u32, out: &mut [u8]) {
     }
 }
 
-fn quarter_round(state: &mut [u32; 16], a: usize, b: usize, c: usize, d: usize) {
+const fn quarter_round(state: &mut [u32; 16], a: usize, b: usize, c: usize, d: usize) {
     state[a] = state[a].wrapping_add(state[b]);
     state[d] = (state[d] ^ state[a]).rotate_left(16);
     state[c] = state[c].wrapping_add(state[d]);

crates/coinstats/src/stats.rs

@@ -64,7 +64,7 @@ impl CoinStats {
     }
 
     /// Applies per-block height and transaction-count deltas.
-    pub fn finish_block(&mut self, height: u32, tx_delta: u64) {
+    pub const fn finish_block(&mut self, height: u32, tx_delta: u64) {
         self.height = height;
         self.tx_count = self.tx_count.saturating_add(tx_delta);
     }

crates/electrum/src/session.rs

@@ -39,7 +39,7 @@ where
     }
 
     /// Returns mutable subscription state for tests and embedders.
-    pub fn subscriptions_mut(&mut self) -> &mut SessionSubscriptions {
+    pub const fn subscriptions_mut(&mut self) -> &mut SessionSubscriptions {
         &mut self.subscriptions
     }
 

crates/filters/src/gcs.rs

@@ -165,7 +165,7 @@ struct BitWriter<'a> {
 }
 
 impl<'a> BitWriter<'a> {
-    fn new(out: &'a mut Vec<u8>) -> Self {
+    const fn new(out: &'a mut Vec<u8>) -> Self {
         Self {
             out,
             buffer: 0,
@@ -302,14 +302,14 @@ impl SipState {
         }
     }
 
-    fn compress(&mut self, word: u64) {
+    const fn compress(&mut self, word: u64) {
         self.v3 ^= word;
         self.round();
         self.round();
         self.v0 ^= word;
     }
 
-    fn finalize(mut self, word: u64) -> u64 {
+    const fn finalize(mut self, word: u64) -> u64 {
         self.compress(word);
         self.v2 ^= 0xff;
         self.round();
@@ -319,7 +319,7 @@ impl SipState {
         self.v0 ^ self.v1 ^ self.v2 ^ self.v3
     }
 
-    fn round(&mut self) {
+    const fn round(&mut self) {
         self.v0 = self.v0.wrapping_add(self.v1);
         self.v1 = self.v1.rotate_left(13);
         self.v1 ^= self.v0;

crates/filters/tests/bip158_vectors.rs

@@ -98,7 +98,7 @@ fn parse_hash(hex: &str) -> TestResult<Hash256> {
 }
 
 fn hex_to_bytes(hex: &str) -> TestResult<Vec<u8>> {
-    if hex.len() % 2 != 0 {
+    if !hex.len().is_multiple_of(2) {
         return Err("hex string has odd length".into());
     }
     let mut out = Vec::with_capacity(hex.len() / 2);

crates/index/src/index.rs

@@ -136,7 +136,7 @@ impl PendingRows {
         self.header_rows.dedup();
     }
 
-    fn counts(&self) -> IndexRowCounts {
+    const fn counts(&self) -> IndexRowCounts {
         IndexRowCounts {
             txids: self.txid_rows.len(),
             funding: self.funding_rows.len(),

crates/index/src/mempool.rs

@@ -121,7 +121,7 @@ impl MempoolRows {
         rows
     }
 
-    fn counts(&self) -> MempoolRowCounts {
+    const fn counts(&self) -> MempoolRowCounts {
         MempoolRowCounts {
             txids: self.txid_rows.len(),
             funding: self.funding_rows.len(),