feat(biome_js_analyze): add noUselessCatchBinding

.changeset/pink-coats-jog.md

@@ -0,0 +1,12 @@
+---
+"@biomejs/biome": minor
+---
+
+Added the new nursery rule `noUselessCatchBinding`. This rule disallows unnecessary catch bindings.
+
+```diff
+try {
+    // Do something
+- } catch (unused) {}
++ } catch {}
+```

crates/biome_diagnostics_categories/src/categories.rs

@@ -149,25 +149,25 @@ define_categories! {
     "lint/correctness/noVoidElementsWithChildren": "https://biomejs.dev/linter/rules/no-void-elements-with-children",
     "lint/correctness/noVoidTypeReturn": "https://biomejs.dev/linter/rules/no-void-type-return",
     "lint/correctness/useExhaustiveDependencies": "https://biomejs.dev/linter/rules/use-exhaustive-dependencies",
+    "lint/correctness/useGraphqlNamedOperations": "https://biomejs.dev/linter/rules/use-graphql-named-operations",
     "lint/correctness/useHookAtTopLevel": "https://biomejs.dev/linter/rules/use-hook-at-top-level",
     "lint/correctness/useImportExtensions": "https://biomejs.dev/linter/rules/use-import-extensions",
     "lint/correctness/useIsNan": "https://biomejs.dev/linter/rules/use-is-nan",
     "lint/correctness/useJsonImportAttributes": "https://biomejs.dev/linter/rules/use-json-import-attributes",
     "lint/correctness/useJsxKeyInIterable": "https://biomejs.dev/linter/rules/use-jsx-key-in-iterable",
-    "lint/correctness/useGraphqlNamedOperations": "https://biomejs.dev/linter/rules/use-graphql-named-operations",
     "lint/correctness/useParseIntRadix": "https://biomejs.dev/linter/rules/use-parse-int-radix",
     "lint/correctness/useSingleJsDocAsterisk": "https://biomejs.dev/linter/rules/use-single-js-doc-asterisk",
     "lint/correctness/useUniqueElementIds": "https://biomejs.dev/linter/rules/use-unique-element-ids",
     "lint/correctness/useValidForDirection": "https://biomejs.dev/linter/rules/use-valid-for-direction",
     "lint/correctness/useValidTypeof": "https://biomejs.dev/linter/rules/use-valid-typeof",
     "lint/correctness/useYield": "https://biomejs.dev/linter/rules/use-yield",
-    "lint/nursery/noNextAsyncClientComponent": "https://biomejs.dev/linter/rules/no-next-async-client-component",
     "lint/nursery/noColorInvalidHex": "https://biomejs.dev/linter/rules/no-color-invalid-hex",
     "lint/nursery/noFloatingPromises": "https://biomejs.dev/linter/rules/no-floating-promises",
     "lint/nursery/noImplicitCoercion": "https://biomejs.dev/linter/rules/no-implicit-coercion",
     "lint/nursery/noImportCycles": "https://biomejs.dev/linter/rules/no-import-cycles",
     "lint/nursery/noMissingGenericFamilyKeyword": "https://biomejs.dev/linter/rules/no-missing-generic-family-keyword",
     "lint/nursery/noMisusedPromises": "https://biomejs.dev/linter/rules/no-misused-promises",
+    "lint/nursery/noNextAsyncClientComponent": "https://biomejs.dev/linter/rules/no-next-async-client-component",
     "lint/nursery/noNonNullAssertedOptionalChain": "https://biomejs.dev/linter/rules/no-non-null-asserted-optional-chain",
     "lint/nursery/noQwikUseVisibleTask": "https://biomejs.dev/linter/rules/no-qwik-use-visible-task",
     "lint/nursery/noSecrets": "https://biomejs.dev/linter/rules/no-secrets",
@@ -176,6 +176,7 @@ define_categories! {
     "lint/nursery/noUnresolvedImports": "https://biomejs.dev/linter/rules/no-unresolved-imports",
     "lint/nursery/noUnwantedPolyfillio": "https://biomejs.dev/linter/rules/no-unwanted-polyfillio",
     "lint/nursery/noUselessBackrefInRegex": "https://biomejs.dev/linter/rules/no-useless-backref-in-regex",
+    "lint/nursery/noUselessCatchBinding": "https://biomejs.dev/linter/rules/no-useless-catch-binding",
     "lint/nursery/noUselessUndefined": "https://biomejs.dev/linter/rules/no-useless-undefined",
     "lint/nursery/noVueDataObjectDeclaration": "https://biomejs.dev/linter/rules/no-vue-data-object-declaration",
     "lint/nursery/noVueReservedKeys": "https://biomejs.dev/linter/rules/no-vue-reserved-keys",
@@ -359,20 +360,20 @@ define_categories! {
     "lint/suspicious/noUnknownAtRules": "https://biomejs.dev/linter/rules/no-unknown-at-rules",
     "lint/suspicious/noUnsafeDeclarationMerging": "https://biomejs.dev/linter/rules/no-unsafe-declaration-merging",
     "lint/suspicious/noUnsafeNegation": "https://biomejs.dev/linter/rules/no-unsafe-negation",
-    "lint/suspicious/noUselessRegexBackrefs": "https://biomejs.dev/linter/rules/no-useless-regex-backrefs",
     "lint/suspicious/noUselessEscapeInString": "https://biomejs.dev/linter/rules/no-useless-escape-in-string",
+    "lint/suspicious/noUselessRegexBackrefs": "https://biomejs.dev/linter/rules/no-useless-regex-backrefs",
     "lint/suspicious/noVar": "https://biomejs.dev/linter/rules/no-var",
     "lint/suspicious/noWith": "https://biomejs.dev/linter/rules/no-with",
     "lint/suspicious/useAdjacentOverloadSignatures": "https://biomejs.dev/linter/rules/use-adjacent-overload-signatures",
     "lint/suspicious/useAwait": "https://biomejs.dev/linter/rules/use-await",
     "lint/suspicious/useBiomeIgnoreFolder": "https://biomejs.dev/linter/rules/use-biome-ignore-folder",
-    "lint/suspicious/useIterableCallbackReturn": "https://biomejs.dev/linter/rules/use-iterable-callback-return",
     "lint/suspicious/useDefaultSwitchClauseLast": "https://biomejs.dev/linter/rules/use-default-switch-clause-last",
     "lint/suspicious/useErrorMessage": "https://biomejs.dev/linter/rules/use-error-message",
     "lint/suspicious/useGetterReturn": "https://biomejs.dev/linter/rules/use-getter-return",
     "lint/suspicious/useGoogleFontDisplay": "https://biomejs.dev/linter/rules/use-google-font-display",
     "lint/suspicious/useGuardForIn": "https://biomejs.dev/linter/rules/use-guard-for-in",
     "lint/suspicious/useIsArray": "https://biomejs.dev/linter/rules/use-is-array",
+    "lint/suspicious/useIterableCallbackReturn": "https://biomejs.dev/linter/rules/use-iterable-callback-return",
     "lint/suspicious/useNamespaceKeyword": "https://biomejs.dev/linter/rules/use-namespace-keyword",
     "lint/suspicious/useNumberToFixedDigitsArgument": "https://biomejs.dev/linter/rules/use-number-to-fixed-digits-argument",
     "lint/suspicious/useStaticResponseMethods": "https://biomejs.dev/linter/rules/use-static-response-methods",

crates/biome_js_analyze/src/lint/nursery.rs

@@ -13,6 +13,7 @@ pub mod no_secrets;
 pub mod no_shadow;
 pub mod no_unnecessary_conditions;
 pub mod no_unresolved_imports;
+pub mod no_useless_catch_binding;
 pub mod no_useless_undefined;
 pub mod no_vue_data_object_declaration;
 pub mod no_vue_reserved_keys;
@@ -26,4 +27,4 @@ pub mod use_max_params;
 pub mod use_qwik_classlist;
 pub mod use_react_function_components;
 pub mod use_sorted_classes;
-declare_lint_group! { pub Nursery { name : "nursery" , rules : [self :: no_floating_promises :: NoFloatingPromises , self :: no_import_cycles :: NoImportCycles , self :: no_misused_promises :: NoMisusedPromises , self :: no_next_async_client_component :: NoNextAsyncClientComponent , self :: no_non_null_asserted_optional_chain :: NoNonNullAssertedOptionalChain , self :: no_qwik_use_visible_task :: NoQwikUseVisibleTask , self :: no_secrets :: NoSecrets , self :: no_shadow :: NoShadow , self :: no_unnecessary_conditions :: NoUnnecessaryConditions , self :: no_unresolved_imports :: NoUnresolvedImports , self :: no_useless_undefined :: NoUselessUndefined , self :: no_vue_data_object_declaration :: NoVueDataObjectDeclaration , self :: no_vue_reserved_keys :: NoVueReservedKeys , self :: no_vue_reserved_props :: NoVueReservedProps , self :: use_anchor_href :: UseAnchorHref , self :: use_consistent_type_definitions :: UseConsistentTypeDefinitions , self :: use_exhaustive_switch_cases :: UseExhaustiveSwitchCases , self :: use_explicit_type :: UseExplicitType , self :: use_image_size :: UseImageSize , self :: use_max_params :: UseMaxParams , self :: use_qwik_classlist :: UseQwikClasslist , self :: use_react_function_components :: UseReactFunctionComponents , self :: use_sorted_classes :: UseSortedClasses ,] } }
+declare_lint_group! { pub Nursery { name : "nursery" , rules : [self :: no_floating_promises :: NoFloatingPromises , self :: no_import_cycles :: NoImportCycles , self :: no_misused_promises :: NoMisusedPromises , self :: no_next_async_client_component :: NoNextAsyncClientComponent , self :: no_non_null_asserted_optional_chain :: NoNonNullAssertedOptionalChain , self :: no_qwik_use_visible_task :: NoQwikUseVisibleTask , self :: no_secrets :: NoSecrets , self :: no_shadow :: NoShadow , self :: no_unnecessary_conditions :: NoUnnecessaryConditions , self :: no_unresolved_imports :: NoUnresolvedImports , self :: no_useless_catch_binding :: NoUselessCatchBinding , self :: no_useless_undefined :: NoUselessUndefined , self :: no_vue_data_object_declaration :: NoVueDataObjectDeclaration , self :: no_vue_reserved_keys :: NoVueReservedKeys , self :: no_vue_reserved_props :: NoVueReservedProps , self :: use_anchor_href :: UseAnchorHref , self :: use_consistent_type_definitions :: UseConsistentTypeDefinitions , self :: use_exhaustive_switch_cases :: UseExhaustiveSwitchCases , self :: use_explicit_type :: UseExplicitType , self :: use_image_size :: UseImageSize , self :: use_max_params :: UseMaxParams , self :: use_qwik_classlist :: UseQwikClasslist , self :: use_react_function_components :: UseReactFunctionComponents , self :: use_sorted_classes :: UseSortedClasses ,] } }

crates/biome_js_analyze/src/lint/nursery/no_useless_catch_binding.rs

@@ -0,0 +1,150 @@
+use crate::JsRuleAction;
+use crate::lint::correctness::no_unused_variables::is_unused;
+use crate::services::semantic::Semantic;
+use biome_analyze::{FixKind, Rule, RuleDiagnostic, context::RuleContext, declare_lint_rule};
+use biome_console::markup;
+use biome_js_syntax::{
+    JsCatchClause, JsCatchClauseFields, JsCatchDeclaration, binding_ext::AnyJsIdentifierBinding,
+};
+use biome_rowan::{AstNode, BatchMutationExt, trim_leading_trivia_pieces};
+use biome_rule_options::no_useless_catch_binding::NoUselessCatchBindingOptions;
+
+declare_lint_rule! {
+    /// Disallow unused catch bindings.
+    ///
+    /// This rule disallows unnecessary catch bindings in accordance with ECMAScript 2019.
+    /// See also: the ECMAScript 2019 “optional catch binding” feature in the language specification.
+    ///
+    /// ## Examples
+    ///
+    /// ### Invalid
+    ///
+    /// ```js,expect_diagnostic
+    /// try {
+    ///     // Do something
+    /// } catch (unused) {}
+    /// ```
+    ///
+    /// ```js,expect_diagnostic
+    /// try {
+    ///     // Do something
+    /// } catch ({ unused }) {}
+    /// ```
+    ///
+    /// ```js,expect_diagnostic
+    /// try {
+    ///     // Do something
+    /// } catch ({ unused1, unused2 }) {}
+    /// ```
+    ///
+    /// ### Valid
+    ///
+    /// ```js
+    /// try {
+    ///     // Do something
+    /// } catch (used) {
+    ///     console.error(used);
+    /// }
+    /// ```
+    ///
+    /// ```js
+    /// try {
+    ///     // Do something
+    /// } catch ({ used }) {
+    ///     console.error(used);
+    /// }
+    /// ```
+    ///
+    /// ```js
+    /// try {
+    ///     // Do something
+    /// } catch ({ used, unused }) {
+    ///     console.error(used);
+    /// }
+    /// ```
+    ///
+    /// ```js
+    /// try {
+    ///     // Do something
+    /// } catch {}
+    /// ```
+    ///
+    pub NoUselessCatchBinding {
+        version: "next",
+        name: "noUselessCatchBinding",
+        language: "js",
+        recommended: false,
+        fix_kind: FixKind::Unsafe,
+    }
+}
+
+impl Rule for NoUselessCatchBinding {
+    type Query = Semantic<JsCatchDeclaration>;
+    type State = ();
+    type Signals = Option<Self::State>;
+    type Options = NoUselessCatchBindingOptions;
+
+    fn run(ctx: &RuleContext<Self>) -> Self::Signals {
+        let model = ctx.model();
+        let catch_declaration = ctx.query();
+        let catch_binding = catch_declaration.binding().ok()?;
+
+        let all_unused = catch_binding
+            .syntax()
+            .descendants()
+            .filter_map(AnyJsIdentifierBinding::cast)
+            .all(|ident| is_unused(model, &ident));
+        if all_unused {
+            return Some(());
+        }
+        None
+    }
+
+    fn diagnostic(ctx: &RuleContext<Self>, _state: &Self::State) -> Option<RuleDiagnostic> {
+        let catch_declaration = ctx.query();
+        Some(
+            RuleDiagnostic::new(
+                rule_category!(),
+                catch_declaration.range(),
+                markup! {
+                    "This "<Emphasis>"catch binding"</Emphasis>" is unused."
+                },
+            )
+            .note(markup! {
+                "Since ECMAScript 2019, catch bindings are optional; you can omit the catch binding if you don't need it."
+            }),
+        )
+    }
+
+    fn action(ctx: &RuleContext<Self>, _state: &Self::State) -> Option<JsRuleAction> {
+        let mut mutation = ctx.root().begin();
+        let node = ctx.query();
+
+        let catch_clause = node.syntax().parent()?;
+        let JsCatchClauseFields {
+            catch_token,
+            declaration,
+            ..
+        } = JsCatchClause::cast(catch_clause)?.as_fields();
+
+        let catch_token = catch_token.ok()?;
+        let declaration = declaration?;
+        let catch_token_replacement =
+            if let Some(trivia) = declaration.syntax().last_trailing_trivia() {
+                catch_token
+                    .clone()
+                    .append_trivia_pieces(trim_leading_trivia_pieces(trivia.pieces()))
+            } else {
+                catch_token.clone()
+            };
+        mutation.remove_node(declaration);
+        mutation.replace_token_discard_trivia(catch_token, catch_token_replacement);
+
+        Some(JsRuleAction::new(
+            ctx.metadata().action_category(ctx.category(), ctx.group()),
+            ctx.metadata().applicability(),
+            markup! { "Remove the catch binding." }.to_owned(),
+            mutation,
+        ))
+    }
+}

crates/biome_js_analyze/tests/specs/nursery/noUselessCatchBinding/invalid.js

@@ -0,0 +1,28 @@
+// should generate diagnostics
+
+try { /* ... */ } catch (unused) { }
+
+try { /* ... */ } catch (_unused) { }
+
+
+try { /* ... */ } catch ({ unused }) { }
+
+try { /* ... */ } catch ({ _unused }) { }
+
+try { /* ... */ } catch ({ unused, _unused }) { }
+
+
+try { /* ... */ } catch (/* leading inner */ unused /* trailing inner */) { }
+
+try { /* ... */ } catch /* leading outer */ (unused) /* trailing outer */ { }
+
+try { /* ... */ } catch /* leading outer */ (/* leading inner */ unused /* trailing inner */) /* trailing outer */ { }
+
+try { /* ... */ } catch /* leading outer */ (/* leading inner 1 */ { /* leading inner 2 */ unused /* trailing inner 2 */ } /* trailing inner 1 */) /* trailing outer */ { }
+
+
+try { /* ... */ } catch ({ used: alias }) { }
+
+try { /* ... */ } catch ({ nested: { unused } }) { }
+
+try { /* ... */ } catch ({ ...rest }) { }