perf(linter/eslint/no-const-assign): batch by declaration (#28356)

Check declaration kinds once and process each bound name without
repeated parent lookups. Reduce fixture callbacks from 37,499 to 31,363.


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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

crates/oxc_linter/src/generated/rule_runner_impls.rs

@@ -550,7 +550,7 @@ impl RuleRunner for crate::rules::eslint::no_console::NoConsole {
 
 impl RuleRunner for crate::rules::eslint::no_const_assign::NoConstAssign {
     const NODE_TYPES: Option<&AstTypesBitset> =
-        Some(&AstTypesBitset::from_types(&[AstType::VariableDeclarator]));
+        Some(&AstTypesBitset::from_types(&[AstType::VariableDeclaration]));
     const RUN_FUNCTIONS: RuleRunFunctionsImplemented = RuleRunFunctionsImplemented::Run;
 }
 

crates/oxc_linter/src/rules/eslint/no_const_assign.rs

@@ -5,7 +5,7 @@ use oxc_macros::declare_oxc_lint;
 use oxc_semantic::{AstNode, SymbolId};
 use oxc_span::Span;
 
-use crate::{ast_util::variable_declaration_kind, context::LintContext, rule::Rule};
+use crate::{context::LintContext, rule::Rule};
 
 fn no_const_assign_diagnostic(name: &str, decl_span: Span, assign_span: Span) -> OxcDiagnostic {
     OxcDiagnostic::warn(format!("Unexpected re-assignment of `const` variable {name}."))
@@ -61,12 +61,11 @@ declare_oxc_lint!(
 
 impl Rule for NoConstAssign {
     fn run<'a>(&self, node: &AstNode<'a>, ctx: &LintContext<'a>) {
-        let AstKind::VariableDeclarator(decl) = node.kind() else { return };
-        let Some(kind) = variable_declaration_kind(decl, ctx.nodes()) else {
-            return;
-        };
-        if kind.is_const() || kind.is_using() {
-            decl.id.bound_names(&mut |ident| check_symbol_id(ident.symbol_id(), ctx));
+        let AstKind::VariableDeclaration(declaration) = node.kind() else { return };
+        if declaration.kind.is_const() || declaration.kind.is_using() {
+            for declarator in &declaration.declarations {
+                declarator.id.bound_names(&mut |ident| check_symbol_id(ident.symbol_id(), ctx));
+            }
         }
     }
 }
@@ -112,6 +111,7 @@ fn test() {
         "using x = foo(); bar(x);",
         "await using x = foo(); bar(x);",
         "type t = (a, ...b) => void",
+        "let a = 1, b = 2; a = 3; b = 4;",
     ];
 
     let fail = vec![
@@ -142,6 +142,8 @@ fn test() {
         "await using x = foo(); [x = baz, y] = bar();",
         "using x = foo(); ({a: x} = bar());",
         "await using x = foo(); ({a: x = baz} = bar());",
+        "const a = 1, {b} = source; a = 2; b = 3;",
+        "using a = foo(), b = bar(); b = baz();",
     ];
 
     Tester::new(NoConstAssign::NAME, NoConstAssign::PLUGIN, pass, fail).test_and_snapshot();

crates/oxc_linter/src/snapshots/eslint_no_const_assign.snap

@@ -226,3 +226,30 @@ source: crates/oxc_linter/src/tester.rs
    ·             ╰── x is declared here as `const`.
    ╰────
   help: Use `let` instead of `const` if you need to reassign this variable.
+
+  ⚠ eslint(no-const-assign): Unexpected re-assignment of `const` variable a.
+   ╭─[no_const_assign.tsx:1:7]
+ 1 │ const a = 1, {b} = source; a = 2; b = 3;
+   ·       ┬                    ┬
+   ·       │                    ╰── a is re-assigned here.
+   ·       ╰── a is declared here as `const`.
+   ╰────
+  help: Use `let` instead of `const` if you need to reassign this variable.
+
+  ⚠ eslint(no-const-assign): Unexpected re-assignment of `const` variable b.
+   ╭─[no_const_assign.tsx:1:15]
+ 1 │ const a = 1, {b} = source; a = 2; b = 3;
+   ·               ┬                   ┬
+   ·               │                   ╰── b is re-assigned here.
+   ·               ╰── b is declared here as `const`.
+   ╰────
+  help: Use `let` instead of `const` if you need to reassign this variable.
+
+  ⚠ eslint(no-const-assign): Unexpected re-assignment of `const` variable b.
+   ╭─[no_const_assign.tsx:1:18]
+ 1 │ using a = foo(), b = bar(); b = baz();
+   ·                  ┬          ┬
+   ·                  │          ╰── b is re-assigned here.
+   ·                  ╰── b is declared here as `const`.
+   ╰────
+  help: Use `let` instead of `const` if you need to reassign this variable.

tasks/track_linter_timings/linter_timings.snap

@@ -42,7 +42,7 @@ eslint/no-class-assign                                  |    300
 eslint/no-compare-neg-zero                              |   9106
 eslint/no-cond-assign                                   |  31699
 eslint/no-console                                       |  95297
-eslint/no-const-assign                                  |  37499
+eslint/no-const-assign                                  |  31363
 eslint/no-constant-binary-expression                    |  32723
 eslint/no-constant-condition                            |  18694
 eslint/no-constructor-return                            |  14199