crates/biome_js_analyze/src/lint/nursery/use_sorted_classes.rs (1)

203-217: Avoid rebuilding custom SortConfig per node

This constructs a custom SortConfig for every matched node. Consider caching once per analysis run (e.g. derive it once when options.classes is present and reuse) to reduce allocations on large files.

crates/biome_js_analyze/src/lint/nursery/use_sorted_classes/sort_config.rs (1)

20-24: Provide unified accessors to avoid map misuse; minor ergonomics

When utilities_owned is Some, layer_index_map is unused. To prevent accidental use, expose helpers that abstract the owned/static split.

Apply this diff to add a safe accessor:

 impl SortConfig {
@@
     pub fn new(preset: &ConfigPreset) -> Self {
@@
         Self {
             utilities: preset.utilities,
             variants: preset.variants,
             layer_index_map,
             utilities_owned: None,
             layer_index_map_owned: None,
         }
     }
+
+    /// Gets the layer index, regardless of owned/static backing.
+    pub fn layer_index(&self, name: &str) -> Option<usize> {
+        if let Some(map) = &self.layer_index_map_owned {
+            map.get(name).copied()
+        } else {
+            self.layer_index_map.get(name).copied()
+        }
+    }
 }

Optional niceties:

• Derive Debug/Clone on UtilityLayerOwned for easier debugging/reuse.
• Reserve capacity when building classes to reduce reallocs:
  let mut classes = Vec::with_capacity(layer.classes.len() + custom_len_estimate);

Also applies to: 45-49, 67-70, 72-130

crates/biome_rule_options/src/use_sorted_classes.rs (1)

8-68: Options wiring LGTM; consider documenting pattern semantics

Deserialisation and validation look solid (unknown keys handled, empties normalised). Consider adding a short rustdoc note on pattern semantics (prefix vs $ exact) to keep this in sync with the rule docs.

Also applies to: 80-83, 119-119, 162-162

crates/biome_js_analyze/src/lint/nursery/use_sorted_classes/class_info.rs (3)

110-149: Nice abstraction with UtilityLayerLike; consider adding an iterator

Current index-based access forces an Option check that’s never None for these impls. An optional iterator method (e.g., classes_iter) would simplify loops and avoid bounds checks.

---

153-210: Longest-prefix match across layers: clarify tie-breaks

The “longest prefix” logic is solid. When lengths tie, the first encountered layer/class wins; that effectively encodes layer order as the tie-breaker. Consider:

• Documenting this explicitly in a comment.
• Adding a test that asserts equal-length tie resolves by layer order (across layers), to lock in behaviour.

---

562-591: Guard against config mismatch (owned utilities vs owned index map)

You select utilities and layer-index map independently. If only one of utilities_owned or layer_index_map_owned is Some, lookups can fail unexpectedly. Add a debug assertion and use a single boolean to drive both selections.

Apply minimal guard:

-    // Use utilities_owned if available, otherwise use static utilities
+    // Use utilities_owned if available, 
10000
otherwise use static utilities.
+    // Both owned fields must be set/unset together.
+    debug_assert_eq!(
+        sort_config.utilities_owned.is_some(),
+        sort_config.layer_index_map_owned.is_some(),
+        "inconsistent SortConfig: utilities_owned and layer_index_map_owned must be set together"
+    );
+    let using_owned = sort_config.utilities_owned.is_some();
-    let utility_info = if let Some(utilities_owned) = &sort_config.utilities_owned {
-        get_utility_info_owned(utilities_owned, &utility_data.utility)
-    } else {
-        get_utility_info(sort_config.utilities, &utility_data.utility)
-    };
+    let utility_info = if using_owned {
+        get_utility_info_owned(
+            // Safe due to the debug_assert above
+            sort_config.utilities_owned.as_ref().unwrap(),
+            &utility_data.utility,
+        )
+    } else {
+        get_utility_info(sort_config.utilities, &utility_data.utility)
+    };
@@
-        // Use owned layer index map if available
-        let layer_index = if let Some(layer_index_map_owned) = &sort_config.layer_index_map_owned {
-            *layer_index_map_owned.get(&utility_info.layer)?
-        } else {
-            *sort_config
-                .layer_index_map
-                .get(utility_info.layer.as_str())?
-        };
+        // Use the matching layer index map consistently with the utilities set
+        let layer_index = if using_owned {
+            *sort_config
+                .layer_index_map_owned
+                .as_ref()
+                .unwrap()
+                .get(utility_info.layer.as_str())?
+        } else {
+            *sort_config
+                .layer_index_map
+                .get(utility_info.layer.as_str())?
+        };

Also please verify that the owned map includes "arbitrary" with the expected index.

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_analyze/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:57:33.228Z
Learning: Applies to crates/biome_analyze/crates/biome_js_analyze/tests/specs/nursery/** : Place snapshot tests for new rules under tests/specs/nursery/<ruleName>/ with files prefixed by invalid* and valid*

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_analyze/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:57:33.228Z
Learning: Applies to crates/biome_analyze/crates/biome_rule_options/lib/*.rs : Define per-rule options in biome_rule_options/lib/<rule>.rs with a dedicated options struct/enum (camelCase serde names, deny_unknown_fields, default) and derive Serialize/Deserialize/Deserializable (and schemars JsonSchema when schema feature is on)

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_analyze/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:57:33.228Z
Learning: Applies to crates/biome_analyze/crates/biome_js_analyze/tests/specs/**/*.jsonc : Use .jsonc files to hold arrays of code snippets for snapshot tests; these snippets run in script mode (no import/export)

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_analyze/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:57:33.228Z
Learning: Applies to crates/biome_analyze/crates/biome_js_analyze/lib/src/lint/nursery/*.rs : Place all new JavaScript lint rules in the nursery group under biome_js_analyze/lib/src/lint/nursery/<rule_name>.rs

Learnt from: dyc3
PR: biomejs/biome#7081
File: packages/@biomejs/biome/configuration_schema.json:7765-7781
Timestamp: 2025-08-05T14:43:29.581Z
Learning: The file `packages/biomejs/biome/configuration_schema.json` is auto-generated and should not be manually edited or reviewed for schema issues; any changes should be made at the code generation source.

crates/biome_js_analyze/tests/specs/nursery/useSortedClasses/customClasses.jsx (1)

1-14: Split into valid/invalid specs**

This file mixes valid and invalid snippets; please split into validCustomClasses.jsx and invalidCustomClasses.jsx (with matching .options.json/.snap) to align with test conventions and avoid flaky discovery.

Based on learnings

crates/biome_js_analyze/src/lint/nursery/use_sorted_classes.rs (2)

176-179: Rename section to “Custom classes ordering”

You cover components and utilities; “utilities” in the heading might mislead. Suggest “Custom classes ordering”.

---

206-221: Avoid rebuilding sort config on every node

This constructs a custom SortConfig for each string literal/template. Consider caching:

• Cache the preset once (LazyLock) and reuse it in with_custom_classes.
• If feasible, cache the computed SortConfig per-options for the rule run.

Minimal change to cache the preset:

@@
-use presets::get_config_preset;
+use presets::{get_config_preset, ConfigPreset};
@@
 static SORT_CONFIG: LazyLock<SortConfig> =
     LazyLock::new(|| SortConfig::new(&get_config_preset(&UseSortedClassesPreset::default())));
+
+static CONFIG_PRESET: LazyLock<ConfigPreset> =
+    LazyLock::new(|| get_config_preset(&UseSortedClassesPreset::default()));
@@
-                    let config = SortConfig::with_custom_classes(
-                        &get_config_preset(&UseSortedClassesPreset::default()),
+                    let config = SortConfig::with_custom_classes(
+                        &CONFIG_PRESET,
                         custom_classes.components.as_deref(),
                         custom_classes.utilities.as_deref(),
                     );

Please sanity-check compile-time constraints around ConfigPreset lifetimes.

crates/biome_js_analyze/src/lint/nursery/use_sorted_classes/sort_config.rs (4)

20-24: Derive Debug/Clone for UtilityLayerOwned

Handy for testing and diagnostics.

-pub struct UtilityLayerOwned {
+#[derive(Debug, Clone)]
+pub struct UtilityLayerOwned {

---

40-49: Scope new fields narrower than pub

Expose as pub(crate) (or keep private with accessors) to avoid leaking internal representation.

-    pub utilities_owned: Option<Vec<UtilityLayerOwned>>,
+    pub(crate) utilities_owned: Option<Vec<UtilityLayerOwned>>,
-    pub layer_index_map_owned: Option<HashMap<String, usize>>,
+    pub(crate) layer_index_map_owned: Option<HashMap<String, usize>>,

---

82-141: with_custom_classes: looks correct; minor polish

Implementation merges as intended; consider small tweaks:

• Inline “arbitrary” index via a const.
• Use extend(custom.iter().map(ToString::to_string)) for brevity.

---

72-81: Unify layer-index access and drop dead_code allowance

• In class_info.rs (line 635), replace the direct .layer_index_map.get(…) call with sort_config.layer_index(utility_info.layer.as_str())?
• Remove #[allow(dead_code)] from layer_index() in sort_config.rs now that it’s used

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_analyze/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:57:33.228Z
Learning: Applies to crates/biome_analyze/crates/biome_js_analyze/tests/specs/nursery/** : Place snapshot tests for new rules under tests/specs/nursery/<ruleName>/ with files prefixed by invalid* and valid*

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_analyze/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:57:33.228Z
Learning: Applies to crates/biome_analyze/crates/biome_js_analyze/lib/src/lint/nursery/*.rs : Place all new JavaScript lint rules in the nursery group under biome_js_analyze/lib/src/lint/nursery/<rule_name>.rs

Learnt from: dyc3
PR: biomejs/biome#7081
File: packages/@biomejs/biome/configuration_schema.json:7765-7781
Timestamp: 2025-08-05T14:43:29.581Z
Learning: The file `packages/biomejs/biome/configuration_schema.json` is auto-generated and should not be manually edited or reviewed for schema issues; any changes should be made at the code generation source.

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_for
8000
matter/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:58:46.845Z
Learning: Applies to crates/biome_formatter/biome_html_formatter/tests/specs/**/options.json : Place an options.json file alongside test cases to apply non-default Biome options to all tests in that folder

Learnt from: CR
PR: biomejs/biome#0
File: crates/biome_analyze/CONTRIBUTING.md:0-0
Timestamp: 2025-10-02T12:57:33.228Z
Learning: Applies to crates/biome_analyze/crates/biome_js_analyze/tests/specs/**/*.jsonc : Use .jsonc files to hold arrays of code snippets for snapshot tests; these snippets run in script mode (no import/export)