Replace allow with expect where possible

If some check always (independent of configuration) triggers for some
code, it is better to use expect because we will be notified when the
check stops triggering.

Some uses of "allow" remain. We could try to replace them with
`cfg_attr` magic, but it would be compplicated in many cases and I feel
that it won't bring much benefit.

Author: Lorak-mmk

examples/basic.rs

@@ -61,7 +61,7 @@ async fn main() -> Result<()> {
     }
 
     // Or as custom structs that derive DeserializeRow
-    #[allow(unused)]
+    #[expect(unused)]
     #[derive(Debug, DeserializeRow)]
     struct RowData {
         a: i32,

scylla-cql/src/deserialize/result.rs

@@ -175,7 +175,7 @@ impl RawRowLendingIterator {
     /// The column iterator must be consumed before the rows iterator can
     /// continue.
     #[inline]
-    #[allow(clippy::should_implement_trait)] // https://github.com/rust-lang/rust-clippy/issues/5004
+    #[expect(clippy::should_implement_trait)] // https://github.com/rust-lang/rust-clippy/issues/5004
     pub fn next(&mut self) -> Option<Result<ColumnIterator, DeserializationError>> {
         self.remaining = self.remaining.checked_sub(1)?;
 

scylla-cql/src/deserialize/row_tests.rs

@@ -932,9 +932,9 @@ fn metadata_does_not_bound_deserialized_rows() {
         #[derive(DeserializeRow)]
         #[scylla(crate=crate)]
         struct MyRow<'frame> {
-            #[allow(dead_code)]
+            #[expect(dead_code)]
             bytes: &'frame [u8],
-            #[allow(dead_code)]
+            #[expect(dead_code)]
             text: &'frame str,
         }
         let decoded_custom_struct_res = deserialize::<MyRow>(row_typ, &bytes);

scylla-cql/src/deserialize/value_tests.rs

@@ -42,7 +42,7 @@ fn test_custom_cassandra_type_parser() {
             dimensions: 5,
         },
     ),
-    (  "636f6c756d6e:org.apache.cassandra.db.marshal.ListType(org.apache.cassandra.db.marshal.Int32Type)", 
+    (  "636f6c756d6e:org.apache.cassandra.db.marshal.ListType(org.apache.cassandra.db.marshal.Int32Type)",
         ColumnType::Collection {
             frozen: false,
             typ: CollectionType::List(Box::new(ColumnType::Native(NativeType::Int))),
@@ -2781,9 +2781,9 @@ fn metadata_does_not_bound_deserialized_values() {
         #[derive(DeserializeValue)]
         #[scylla(crate=crate)]
         struct Udt<'frame> {
-            #[allow(dead_code)]
+            #[expect(dead_code)]
             bytes: &'frame [u8],
-            #[allow(dead_code)]
+            #[expect(dead_code)]
             text: &'frame str,
         }
         let decoded_udt_res = deserialize::<Udt>(&udt_typ, &bytes);

scylla-cql/src/frame/request/mod.rs

@@ -162,7 +162,7 @@ impl Request<'_> {
             Request::Query(q) => Some(q.parameters.consistency),
             Request::Execute(e) => Some(e.parameters.consistency),
             Request::Batch(b) => Some(b.consistency),
-            #[allow(unreachable_patterns)] // until other opcodes are supported
+            #[expect(unreachable_patterns)] // until other opcodes are supported
             _ => None,
         }
     }
@@ -173,7 +173,7 @@ impl Request<'_> {
             Request::Query(q) => Some(q.parameters.serial_consistency),
             Request::Execute(e) => Some(e.parameters.serial_consistency),
             Request::Batch(b) => Some(b.serial_consistency),
-            #[allow(unreachable_patterns)] // until other opcodes are supported
+            #[expect(unreachable_patterns)] // until other opcodes are supported
             _ => None,
         }
     }

scylla-cql/src/frame/response/result.rs

@@ -260,7 +260,7 @@ impl ColumnType<'_> {
     // Scylla's set of types supported for empty values as it's smaller;
     // with Cassandra, some rejects will just have to be rejected on the db side.
     pub(crate) fn supports_special_empty_value(&self) -> bool {
-        #[allow(clippy::match_like_matches_macro)]
+        #[expect(clippy::match_like_matches_macro)]
         match self {
             ColumnType::Native(NativeType::Counter)
             | ColumnType::Native(NativeType::Duration)

scylla-cql/src/serialize/row_tests.rs

@@ -669,7 +669,7 @@ struct TestRowWithSkippedFields {
     a: String,
     b: i32,
     #[scylla(skip)]
-    #[allow(dead_code)]
+    #[expect(dead_code)]
     skipped: Vec<String>,
     c: Vec<i64>,
 }

scylla-cql/src/serialize/value_tests.rs

@@ -522,7 +522,7 @@ fn test_cql_value_udt_errors() {
 // Do not remove. It's not used in tests but we keep it here to check that
 // we properly ignore warnings about unused variables, unnecessary `mut`s
 // etc. that usually pop up when generating code for empty structs.
-#[allow(unused)]
+#[expect(unused)]
 #[derive(SerializeValue)]
 #[scylla(crate = crate)]
 struct TestUdtWithNoFields {}
@@ -1162,7 +1162,7 @@ fn test_udt_serialization_with_field_rename_and_enforce_order() {
     assert_eq!(reference, udt);
 }
 
-#[allow(unused)]
+#[expect(unused)]
 #[derive(SerializeValue, Debug)]
 #[scylla(crate = crate, flavor = "enforce_order", skip_name_checks)]
 struct TestUdtWithSkippedNameChecks {
@@ -1329,7 +1329,7 @@ struct TestUdtWithSkippedFields {
     a: String,
     b: i32,
     #[scylla(skip)]
-    #[allow(dead_code)]
+    #[expect(dead_code)]
     skipped: Vec<String>,
     c: Vec<i64>,
 }

scylla-macros/src/serialize/row.rs

@@ -396,7 +396,7 @@ impl Generator for ColumnSortingGenerator<'_> {
                 #partial_struct
                 #partial_serialize
 
-                #[allow(non_local_definitions)]
+                #[expect(non_local_definitions)]
                 #serialize_by_name
 
                 #crate_path::ser::row::ByName::<Self>::serialize(#crate_path::ser::row::ByName(self), ctx, writer)
@@ -447,7 +447,7 @@ impl Generator for ColumnOrderedGenerator<'_> {
                 ctx: &#crate_path::RowSerializationContext,
                 writer: &mut #crate_path::RowWriter<'_scylla_ser_row_writer_buffer>,
             ) -> ::std::result::Result<(), #crate_path::SerializationError> {
-                #[allow(non_local_definitions)]
+                #[expect(non_local_definitions)]
                 impl #impl_generics #crate_path::SerializeRowInOrder for #struct_name #ty_generics #where_clause {
                     fn serialize_in_order(
                         &self,

scylla-proxy/src/actions.rs

@@ -121,7 +121,7 @@ impl Condition {
     }
 
     /// A convenience function for creating [Condition::Not] variant.
-    #[allow(clippy::should_implement_trait)]
+    #[expect(clippy::should_implement_trait)]
     pub fn not(c: Self) -> Self {
         Condition::Not(Box::new(c))
     }