Sweep the pinned toolchain to Rust 1.97

The Windows UI needs current winsafe, whose real minimum is 1.89 (its manifest
under-declares 1.87 while it uses NonNull::from_ref). Rather than stop at the
minimum, this goes to current stable and fixes what that costs.

The counter-intuitive result: 1.97 is CHEAPER than 1.89. libfreemkv had 54
clippy errors at 1.89 and 6 at 1.97, because clippy tightened the noisy
collapsible_if lint in between. Stopping at the minimum would have been the most
expensive choice available.

Roughly 47 lints across the eight repos, the large majority auto-fixed:
libfreemkv 6, freemkv-engine 14, bdemu 8, freemkv-keysources 7, autorip 6,
freemkv-unlock 3, freemkv-i18n 3. The hand-fixed ones are a descending sort to
sort_by_key(Reverse), four manual checked-division sites, a loop counter replaced
by enumerate, and a loop whose first let-else became a while-let.

Worth recording for whoever bumps next: clippy is MSRV-AWARE. Those 54 lints only
appear once the crate DECLARES 1.89 or later, because let-chains become
available. A bare `cargo +1.89 clippy` against a manifest still pinned at 1.87
reports clean and is meaningless — gate with the real precommit script, which is
also the only thing that covers build scripts.

The pin still sits below the Mac default, so it keeps doing its job: catching
lint drift locally before CI sees it.

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
-      - uses: dtolnay/rust-toolchain@1.87.0
+      - uses: dtolnay/rust-toolchain@1.97.0
         with:
           components: clippy, rustfmt
       # Cache ~/.cargo/registry + target/ across runs. Saves ~30-60s
@@ -29,7 +29,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
-      - uses: dtolnay/rust-toolchain@1.87.0
+      - uses: dtolnay/rust-toolchain@1.97.0
       - uses: Swatinem/rust-cache@v2
         with:
           shared-key: freemkv-keysources-ci

.github/workflows/release.yml

@@ -36,7 +36,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
-      - uses: dtolnay/rust-toolchain@1.87.0
+      - uses: dtolnay/rust-toolchain@1.97.0
       - uses: Swatinem/rust-cache@v2
       - run: cargo test
 

Cargo.toml

@@ -2,7 +2,7 @@
 name = "freemkv-keysources"
 version = "1.6.0"
 edition = "2024"
-rust-version = "1.87"
+rust-version = "1.97"
 license = "MIT"
 description = "Pluggable AACS key sources (keydb, online key service) for libfreemkv. Each source looks a disc up and hands libfreemkv its terminal Unit Keys via get_unit_keys; the library does all derivation."
 repository = "https://github.com/freemkv/freemkv-keysources"

src/keydb_format.rs

@@ -698,22 +698,19 @@ impl KeyDb {
                         i += 1;
                     }
                 }
-                "U" => {
-                    if i + 1 < parts.len() {
-                        // Unit keys: "1-0xKEY" or "1-0xKEY ; comment"
-                        let uk_str = parts[i + 1].split(';').next().unwrap_or("").trim();
-                        for uk in uk_str.split(' ') {
-                            let uk = uk.trim();
-                            if let Some((num, key)) = uk.split_once('-') {
-                                if let Ok(n) = num.parse::<u32>() {
-                                    if let Some(k) = parse_hex16(key) {
-                                        unit_keys.push((n, k));
-                                    }
-                                }
-                            }
+                "U" if i + 1 < parts.len() => {
+                    // Unit keys: "1-0xKEY" or "1-0xKEY ; comment"
+                    let uk_str = parts[i + 1].split(';').next().unwrap_or("").trim();
+                    for uk in uk_str.split(' ') {
+                        let uk = uk.trim();
+                        if let Some((num, key)) = uk.split_once('-')
+                            && let Ok(n) = num.parse::<u32>()
+                            && let Some(k) = parse_hex16(key)
+                        {
+                            unit_keys.push((n, k));
                         }
-                        i += 1;
                     }
+                    i += 1;
                 }
                 _ => {}
             }

src/lib.rs

@@ -78,10 +78,10 @@ impl KeySource for MultiSource {
     /// the chain). All sources exhausted → empty.
     fn get_unit_keys(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, libfreemkv::Error> {
         for s in &self.sources {
-            if let Ok(uks) = s.get_unit_keys(ctx) {
-                if !uks.is_empty() {
-                    return Ok(uks);
-                }
+            if let Ok(uks) = s.get_unit_keys(ctx)
+                && !uks.is_empty()
+            {
+                return Ok(uks);
             }
         }
         Ok(Vec::new())
@@ -93,10 +93,10 @@ impl KeySource for MultiSource {
     /// is skipped; on today's discs the online source answers.
     fn get_fmts_indexes(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, libfreemkv::Error> {
         for s in &self.sources {
-            if let Ok(uks) = s.get_fmts_indexes(ctx) {
-                if !uks.is_empty() {
-                    return Ok(uks);
-                }
+            if let Ok(uks) = s.get_fmts_indexes(ctx)
+                && !uks.is_empty()
+            {
+                return Ok(uks);
             }
         }
         Ok(Vec::new())

src/online.rs

@@ -292,10 +292,10 @@ impl OnlineSource {
         );
         // The disc's own title (UDF/ISO volume id), plain text. The key service
         // catalogs it by disc_hash (its disc-titles.json) — independent of keydb.
-        if let Some(label) = ctx.title().map(str::trim) {
-            if !label.is_empty() {
-                body["title"] = serde_json::Value::String(label.to_string());
-            }
+        if let Some(label) = ctx.title().map(str::trim)
+            && !label.is_empty()
+        {
+            body["title"] = serde_json::Value::String(label.to_string());
         }
         // Resolve + SSRF-guard the host just before the POST; pin the
         // validated addresses into a redirect-disabled agent so a DNS