From 3bc3251eb81022b9b17b4ae5ce2dd50292f1e3bb Mon Sep 17 00:00:00 2001
From: Stefan Steiner <ssteiner@tableau.com>
Date: Mon, 5 Oct 2026 12:04:54 -0700
Subject: [PATCH] fix(ci): satisfy Rust 1.99 clippy lints

CI tracks the moving stable toolchain, and 1.99 added/tightened lints that
fail the -D warnings clippy gate:
- must_use_candidate on six accessor methods in hyperdb-api
- assert_is_empty on assert!(x.is_empty()) in tests (use assert_eq!/assert_ne!)
- unfulfilled #[expect(clippy::float_cmp)] in hyperdb-api-core tests, which
  1.99 no longer triggers

No behaviour change.
---
 hyperdb-api-core/src/client/auth.rs       |  2 +-
 hyperdb-api-core/src/client/prepare.rs    | 10 +---------
 hyperdb-api-core/src/protocol/copy.rs     |  2 +-
 hyperdb-api-core/src/protocol/types.rs    |  4 ----
 hyperdb-api-core/src/types/special.rs     | 10 +---------
 hyperdb-api/src/grpc_connection.rs        |  2 ++
 hyperdb-api/src/inserter.rs               |  1 +
 hyperdb-api/src/names.rs                  |  5 ++++-
 hyperdb-api/tests/arrow_reader_tests.rs   | 22 +++++++++++-----------
 hyperdb-api/tests/async_kv_store_tests.rs |  2 +-
 hyperdb-api/tests/kv_store_in_tests.rs    |  4 ++--
 hyperdb-api/tests/kv_store_tests.rs       |  5 ++++-
 hyperdb-api/tests/process_tests.rs        |  4 ++--
 hyperdb-api/tests/type_tests.rs           |  2 +-
 hyperdb-bootstrap/src/release.rs          |  2 +-
 hyperdb-mcp/tests/attach_tests.rs         |  2 +-
 hyperdb-mcp/tests/diagnostics_tests.rs    | 10 ++++++++--
 hyperdb-mcp/tests/inspect_tests.rs        |  5 ++++-
 hyperdb-mcp/tests/subscription_tests.rs   |  6 +++---
 19 files changed, 49 insertions(+), 51 deletions(-)

diff --git a/hyperdb-api-core/src/client/auth.rs b/hyperdb-api-core/src/client/auth.rs
index b32d1c8b..9b6dc60e 100644
--- a/hyperdb-api-core/src/client/auth.rs
+++ b/hyperdb-api-core/src/client/auth.rs
@@ -390,6 +390,6 @@ mod tests {
         let nonce1 = generate_nonce();
         let nonce2 = generate_nonce();
         assert_ne!(nonce1, nonce2);
-        assert!(!nonce1.is_empty());
+        assert_ne!(nonce1, "");
     }
 }
diff --git a/hyperdb-api-core/src/client/prepare.rs b/hyperdb-api-core/src/client/prepare.rs
index 319b7a31..e51710c4 100644
--- a/hyperdb-api-core/src/client/prepare.rs
+++ b/hyperdb-api-core/src/client/prepare.rs
@@ -692,10 +692,6 @@ mod tests {
     }
 
     #[test]
-    #[expect(
-        clippy::float_cmp,
-        reason = "1.5 is exactly representable; encode/decode must round-trip bit-for-bit"
-    )]
     fn test_sql_param_f32() {
         let encoded = 1.5_f32.encode();
         assert_eq!(encoded.len(), 4);
@@ -704,10 +700,6 @@ mod tests {
     }
 
     #[test]
-    #[expect(
-        clippy::float_cmp,
-        reason = "1.5 is exactly representable; encode/decode must round-trip bit-for-bit"
-    )]
     fn test_sql_param_f64() {
         let encoded = 1.5_f64.encode();
         assert_eq!(encoded.len(), 8);
@@ -748,7 +740,7 @@ mod tests {
     #[test]
     fn test_params_macro_empty() {
         let p = params![];
-        assert!(p.is_empty());
+        assert_eq!(p.len(), 0);
     }
 
     #[test]
diff --git a/hyperdb-api-core/src/protocol/copy.rs b/hyperdb-api-core/src/protocol/copy.rs
index e26bdeac..a6292f84 100644
--- a/hyperdb-api-core/src/protocol/copy.rs
+++ b/hyperdb-api-core/src/protocol/copy.rs
@@ -773,7 +773,7 @@ mod tests {
         // A zero-length value is valid: 4 bytes of length prefix, no data.
         let buf = [0x00, 0x00, 0x00, 0x00];
         let bytes = read_varbinary(&buf).unwrap();
-        assert!(bytes.is_empty());
+        assert_eq!(bytes.len(), 0);
     }
 
     #[test]
diff --git a/hyperdb-api-core/src/protocol/types.rs b/hyperdb-api-core/src/protocol/types.rs
index b9f62ce4..4a17cd39 100644
--- a/hyperdb-api-core/src/protocol/types.rs
+++ b/hyperdb-api-core/src/protocol/types.rs
@@ -423,10 +423,6 @@ mod tests {
     }
 
     #[test]
-    #[expect(
-        clippy::float_cmp,
-        reason = "bit-for-bit round-trip through fixed-width binary encoding; epsilon compare would mask a decode regression"
-    )]
     fn test_f64_roundtrip() {
         let mut buf = BytesMut::new();
         f64_to_hyper_binary(std::f64::consts::PI, &mut buf);
diff --git a/hyperdb-api-core/src/types/special.rs b/hyperdb-api-core/src/types/special.rs
index 05d58e62..2fbcde9f 100644
--- a/hyperdb-api-core/src/types/special.rs
+++ b/hyperdb-api-core/src/types/special.rs
@@ -2182,7 +2182,7 @@ mod geo_impl {
             let wkb_geo = Geography::from_wkt("POINT(1 2)").expect("wkt to wkb");
             match wkb_geo.format().expect("format detection") {
                 GeographyFormat::Wkb(bytes) => {
-                    assert!(!bytes.is_empty());
+                    assert_ne!(bytes.len(), 0);
                     assert!(bytes[0] == 0 || bytes[0] == 1);
                 }
                 GeographyFormat::Legacy(_) => panic!("expected WKB format"),
@@ -2460,10 +2460,6 @@ mod tests {
     }
 
     #[test]
-    #[expect(
-        clippy::float_cmp,
-        reason = "42.0 is exactly representable; scale=0 conversion must be bit-exact"
-    )]
     fn test_numeric_from_binary_with_scale_zero() {
         // Unscaled value 42 with scale 0 = 42
         let mut bytes = [0u8; 16];
@@ -2571,10 +2567,6 @@ mod tests {
     }
 
     #[test]
-    #[expect(
-        clippy::float_cmp,
-        reason = "123.0 is exactly representable; scale=0 conversion must be bit-exact"
-    )]
     fn test_numeric_from_binary_with_scale_required() {
         // FromHyperBinary is intentionally NOT implemented for Numeric because
         // the scale must be obtained from type metadata - it cannot be inferred
diff --git a/hyperdb-api/src/grpc_connection.rs b/hyperdb-api/src/grpc_connection.rs
index 78e75f16..5aa1ef83 100644
--- a/hyperdb-api/src/grpc_connection.rs
+++ b/hyperdb-api/src/grpc_connection.rs
@@ -290,6 +290,7 @@ impl GrpcConnection {
     }
 
     /// Returns the gRPC configuration.
+    #[must_use]
     pub fn config(&self) -> &GrpcConfig {
         self.client.config()
     }
@@ -425,6 +426,7 @@ impl GrpcConnectionAsync {
     }
 
     /// Returns the gRPC configuration.
+    #[must_use]
     pub fn config(&self) -> &GrpcConfig {
         self.client.config()
     }
diff --git a/hyperdb-api/src/inserter.rs b/hyperdb-api/src/inserter.rs
index 56894647..6d5b5fb0 100644
--- a/hyperdb-api/src/inserter.rs
+++ b/hyperdb-api/src/inserter.rs
@@ -284,6 +284,7 @@ impl<'conn> Inserter<'conn> {
     }
 
     /// Returns the table definition.
+    #[must_use]
     pub fn table_definition(&self) -> &TableDefinition {
         &self.table_def
     }
diff --git a/hyperdb-api/src/names.rs b/hyperdb-api/src/names.rs
index 83331200..4d0225ac 100644
--- a/hyperdb-api/src/names.rs
+++ b/hyperdb-api/src/names.rs
@@ -314,6 +314,7 @@ impl DatabaseName {
     }
 
     /// Returns the name component.
+    #[must_use]
     pub fn name(&self) -> &Name {
         &self.name
     }
@@ -449,6 +450,7 @@ impl SchemaName {
     }
 
     /// Returns the schema name component.
+    #[must_use]
     pub fn schema(&self) -> &Name {
         &self.schema
     }
@@ -638,6 +640,7 @@ impl TableName {
     }
 
     /// Returns the table name component.
+    #[must_use]
     pub fn table(&self) -> &Name {
         &self.table
     }
@@ -877,7 +880,7 @@ mod tests {
         let name = Name::try_new("users").unwrap();
         assert_eq!(name.to_string(), "\"users\"");
         assert_eq!(name.unescaped(), "users");
-        assert!(!name.unescaped().is_empty());
+        assert_ne!(name.unescaped(), "");
     }
 
     #[test]
diff --git a/hyperdb-api/tests/arrow_reader_tests.rs b/hyperdb-api/tests/arrow_reader_tests.rs
index 778de850..b56505da 100644
--- a/hyperdb-api/tests/arrow_reader_tests.rs
+++ b/hyperdb-api/tests/arrow_reader_tests.rs
@@ -56,11 +56,11 @@ fn test_arrow_reader_query() -> Result<()> {
 
     // Test query with filter
     let arrow_data = reader.query_to_arrow("SELECT * FROM products WHERE price > 15")?;
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     // Test query with aggregation
     let arrow_data = reader.query_to_arrow("SELECT COUNT(*), SUM(price) FROM products")?;
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     Ok(())
 }
@@ -80,7 +80,7 @@ fn test_arrow_reader_columns() -> Result<()> {
 
     // Read only specific columns
     let arrow_data = reader.table_columns_to_arrow("users", &["id", "name"])?;
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     Ok(())
 }
@@ -106,7 +106,7 @@ fn test_arrow_reader_filtered() -> Result<()> {
 
     // Read with filter
     let arrow_data = reader.table_filtered_to_arrow("orders", "status = 'pending'")?;
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     Ok(())
 }
@@ -161,7 +161,7 @@ fn test_arrow_reader_empty_table() -> Result<()> {
     let arrow_data = reader.table_to_arrow("empty_table")?;
 
     // Even empty result should have some data (schema at minimum)
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     Ok(())
 }
@@ -192,7 +192,7 @@ fn test_arrow_reader_various_types() -> Result<()> {
 
     let reader = ArrowReader::new(&conn);
     let arrow_data = reader.table_to_arrow("typed_data")?;
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     Ok(())
 }
@@ -213,7 +213,7 @@ fn test_arrow_reader_no_matching_rows() -> Result<()> {
     let arrow_data = reader.query_to_arrow("SELECT * FROM test_filter WHERE id > 100")?;
 
     // Should still have data (schema)
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     Ok(())
 }
@@ -233,7 +233,7 @@ fn test_arrow_reader_schema_qualified() -> Result<()> {
 
     let reader = ArrowReader::new(&conn);
     let arrow_data = reader.table_to_arrow("custom_schema.test_table")?;
-    assert!(!arrow_data.is_empty());
+    assert_ne!(arrow_data, [] as [u8; 0]);
 
     Ok(())
 }
@@ -256,9 +256,9 @@ fn test_arrow_reader_multiple_reads() -> Result<()> {
     let data2 = reader.table_to_arrow("multi_test")?;
     let data3 = reader.query_to_arrow("SELECT COUNT(*) FROM multi_test")?;
 
-    assert!(!data1.is_empty());
-    assert!(!data2.is_empty());
-    assert!(!data3.is_empty());
+    assert_ne!(data1, [] as [u8; 0]);
+    assert_ne!(data2, [] as [u8; 0]);
+    assert_ne!(data3, [] as [u8; 0]);
 
     // Same query should return same size
     assert_eq!(data1.len(), data2.len());
diff --git a/hyperdb-api/tests/async_kv_store_tests.rs b/hyperdb-api/tests/async_kv_store_tests.rs
index c572205f..1d08fa8f 100644
--- a/hyperdb-api/tests/async_kv_store_tests.rs
+++ b/hyperdb-api/tests/async_kv_store_tests.rs
@@ -71,7 +71,7 @@ async fn async_kv_full_surface() -> Result<()> {
 #[tokio::test(flavor = "current_thread")]
 async fn async_list_stores_and_validation() -> Result<()> {
     let (_hyper, conn) = fresh_async_conn("async_kv_list").await?;
-    assert!(conn.kv_list_stores().await?.is_empty());
+    assert_eq!(conn.kv_list_stores().await?, [] as [std::string::String; 0]);
     let _ = conn.kv_store("alpha").await?.set("k", "1").await?;
     let _ = conn.kv_store("beta").await?.set("k", "2").await?;
     let mut stores = conn.kv_list_stores().await?;
diff --git a/hyperdb-api/tests/kv_store_in_tests.rs b/hyperdb-api/tests/kv_store_in_tests.rs
index 91d5656f..354ed727 100644
--- a/hyperdb-api/tests/kv_store_in_tests.rs
+++ b/hyperdb-api/tests/kv_store_in_tests.rs
@@ -56,7 +56,7 @@ fn kv_store_in_targets_attached_database() -> Result<()> {
 
     // The location-aware listing sees the attached-DB store; the primary has none.
     assert_eq!(conn.kv_list_stores_in("aux")?, vec!["settings".to_string()]);
-    assert!(conn.kv_list_stores()?.is_empty());
+    assert_eq!(conn.kv_list_stores()?, [] as [std::string::String; 0]);
 
     Ok(())
 }
@@ -108,7 +108,7 @@ async fn async_kv_store_in_targets_attached_database() -> Result<()> {
         conn.kv_list_stores_in("aux").await?,
         vec!["settings".to_string()]
     );
-    assert!(conn.kv_list_stores().await?.is_empty());
+    assert_eq!(conn.kv_list_stores().await?, [] as [std::string::String; 0]);
 
     Ok(())
 }
diff --git a/hyperdb-api/tests/kv_store_tests.rs b/hyperdb-api/tests/kv_store_tests.rs
index a8ccd4f6..de99afd5 100644
--- a/hyperdb-api/tests/kv_store_tests.rs
+++ b/hyperdb-api/tests/kv_store_tests.rs
@@ -148,7 +148,10 @@ fn delete_exists_size_keys_clear() -> Result<()> {
 fn list_stores_and_isolation() -> Result<()> {
     let tc = TestConnection::new()?;
     // Empty before any store has keys.
-    assert!(tc.connection.kv_list_stores()?.is_empty());
+    assert_eq!(
+        tc.connection.kv_list_stores()?,
+        [] as [std::string::String; 0]
+    );
 
     let a = tc.connection.kv_store("alpha")?;
     let b = tc.connection.kv_store("beta")?;
diff --git a/hyperdb-api/tests/process_tests.rs b/hyperdb-api/tests/process_tests.rs
index 272d3509..de25b515 100644
--- a/hyperdb-api/tests/process_tests.rs
+++ b/hyperdb-api/tests/process_tests.rs
@@ -172,7 +172,7 @@ fn test_hyper_process_start_stop() {
     // Verify the endpoint is valid
     let endpoint = hyper.endpoint().expect("No endpoint");
     let descriptor = endpoint.to_string();
-    assert!(!descriptor.is_empty());
+    assert_ne!(descriptor, "");
 
     // Verify we can connect
     let conn = Connection::without_database(endpoint).expect("Failed to connect");
@@ -310,7 +310,7 @@ fn test_hyper_process_drop() {
     }
     // After hyper is dropped, we can't verify the server is down without
     // trying to connect (which would hang), so we just ensure no panic
-    assert!(!endpoint_str.is_empty());
+    assert_ne!(endpoint_str, "");
 }
 
 #[test]
diff --git a/hyperdb-api/tests/type_tests.rs b/hyperdb-api/tests/type_tests.rs
index f9cf621c..61a93e17 100644
--- a/hyperdb-api/tests/type_tests.rs
+++ b/hyperdb-api/tests/type_tests.rs
@@ -94,7 +94,7 @@ fn test_i64_type_handling() {
             let str_val = row.get::<String>(0);
             assert!(str_val.is_some(), "Should be readable as String");
             // The string might be "42" or binary representation, but should not be empty
-            assert!(!str_val.unwrap().is_empty());
+            assert_ne!(str_val.unwrap(), "");
         }
     }
 
diff --git a/hyperdb-bootstrap/src/release.rs b/hyperdb-bootstrap/src/release.rs
index aaeec1c3..c9cf6928 100644
--- a/hyperdb-bootstrap/src/release.rs
+++ b/hyperdb-bootstrap/src/release.rs
@@ -109,7 +109,7 @@ mod tests {
     #[test]
     fn builtin_parses() {
         let r = PinnedRelease::builtin();
-        assert!(!r.version.is_empty());
+        assert_ne!(r.version, "");
     }
 
     #[test]
diff --git a/hyperdb-mcp/tests/attach_tests.rs b/hyperdb-mcp/tests/attach_tests.rs
index c5e57921..cfc983c9 100644
--- a/hyperdb-mcp/tests/attach_tests.rs
+++ b/hyperdb-mcp/tests/attach_tests.rs
@@ -166,7 +166,7 @@ fn detach_removes_entry_and_hides_tables() {
     // Should surface as a SQL error (attached database not found). We
     // don't pin the exact ErrorCode here — we only care that the
     // query is rejected.
-    assert!(!err.message.is_empty());
+    assert_ne!(err.message, "");
 }
 
 #[test]
diff --git a/hyperdb-mcp/tests/diagnostics_tests.rs b/hyperdb-mcp/tests/diagnostics_tests.rs
index fa5b1476..ab79bba4 100644
--- a/hyperdb-mcp/tests/diagnostics_tests.rs
+++ b/hyperdb-mcp/tests/diagnostics_tests.rs
@@ -57,7 +57,10 @@ fn non_utf8_os_string() -> OsString {
 fn launcher_identity_parsing_contract() {
     let absent = parse_launcher_identity(None);
     assert_eq!(absent.identity, None);
-    assert!(absent.warnings.is_empty());
+    assert_eq!(
+        absent.warnings,
+        [] as [hyperdb_mcp::diagnostics::IdentityWarning; 0]
+    );
 
     let secret = "UNKNOWN_SECRET_SENTINEL_4c4c08";
     let valid = json!({
@@ -79,7 +82,10 @@ fn launcher_identity_parsing_contract() {
     .to_string();
 
     let parsed = parse_launcher_identity(Some(OsStr::new(&valid)));
-    assert!(parsed.warnings.is_empty());
+    assert_eq!(
+        parsed.warnings,
+        [] as [hyperdb_mcp::diagnostics::IdentityWarning; 0]
+    );
     let identity = parsed.identity.expect("valid launcher metadata must parse");
     assert_eq!(
         serde_json::to_value(&identity).expect("launcher identity must serialize"),
diff --git a/hyperdb-mcp/tests/inspect_tests.rs b/hyperdb-mcp/tests/inspect_tests.rs
index 118cca85..cb0934a0 100644
--- a/hyperdb-mcp/tests/inspect_tests.rs
+++ b/hyperdb-mcp/tests/inspect_tests.rs
@@ -46,7 +46,10 @@ fn inspect_csv_reports_widened_types_and_min_max() {
     assert_eq!(report.stats[pop].max_i128, Some(8_000_000_000));
     assert_eq!(report.stats[pop].min_i128, Some(100));
     assert_eq!(report.stats[pop].null_count, 0);
-    assert!(!report.stats[pop].sample_values.is_empty());
+    assert_ne!(
+        report.stats[pop].sample_values,
+        [] as [std::string::String; 0]
+    );
 }
 
 /// Nulls and empty cells must be counted, not silently dropped — the caller
diff --git a/hyperdb-mcp/tests/subscription_tests.rs b/hyperdb-mcp/tests/subscription_tests.rs
index b9c21338..3aee0f72 100644
--- a/hyperdb-mcp/tests/subscription_tests.rs
+++ b/hyperdb-mcp/tests/subscription_tests.rs
@@ -18,7 +18,7 @@ use hyperdb_mcp::subscriptions::{
 #[test]
 fn empty_registry_has_no_subscribed_uris() {
     let reg = SubscriptionRegistry::new();
-    assert!(reg.subscribed_uris().is_empty());
+    assert_eq!(reg.subscribed_uris(), [] as [std::string::String; 0]);
     assert!(reg.subscribers_for("hyper://anything").is_empty());
 }
 
@@ -32,7 +32,7 @@ fn unsubscribe_on_empty_registry_is_a_noop() {
     // subscribers_for after an unsubscribe should still be empty.
     assert_eq!(reg.subscribers_for("hyper://workspace").len(), 0);
     reg.clear();
-    assert!(reg.subscribed_uris().is_empty());
+    assert_eq!(reg.subscribed_uris(), [] as [std::string::String; 0]);
 }
 
 #[test]
@@ -43,7 +43,7 @@ fn notify_updated_on_empty_registry_is_safe() {
     reg.notify_updated("hyper://workspace");
     reg.notify_list_changed();
     // Should still have no subscribers after the no-op.
-    assert!(reg.subscribed_uris().is_empty());
+    assert_eq!(reg.subscribed_uris(), [] as [std::string::String; 0]);
 }
 
 // --- URI fan-out helpers ----------------------------------------------------