fix(isolated-declarations): false positives for non-exported binding elements (#3751)

crates/oxc_isolated_declarations/src/declaration.rs

@@ -1,13 +1,15 @@
 use oxc_allocator::Box;
 #[allow(clippy::wildcard_imports)]
 use oxc_ast::ast::*;
-use oxc_ast::Visit;
+use oxc_ast::{syntax_directed_operations::BoundNames, Visit};
 use oxc_diagnostics::OxcDiagnostic;
 use oxc_span::{GetSpan, SPAN};
 use oxc_syntax::scope::ScopeFlags;
 
 use crate::{
-    diagnostics::{inferred_type_of_expression, signature_computed_property_name},
+    diagnostics::{
+        binding_element_export, inferred_type_of_expression, signature_computed_property_name,
+    },
     IsolatedDeclarations,
 };
 
@@ -47,9 +49,13 @@ impl<'a> IsolatedDeclarations<'a> {
         check_binding: bool,
     ) -> Option<VariableDeclarator<'a>> {
         if decl.id.kind.is_destructuring_pattern() {
-            self.error(OxcDiagnostic::error(
-                "Binding elements can't be exported directly with --isolatedDeclarations.",
-            ));
+            if check_binding {
+                decl.id.bound_names(&mut |id| {
+                    if self.scope.has_reference(&id.name) {
+                        self.error(binding_element_export(id.span));
+                    }
+                });
+            }
             return None;
         }
 

crates/oxc_isolated_declarations/src/diagnostics.rs

@@ -95,3 +95,8 @@ pub fn implicitly_adding_undefined_to_type(span: Span) -> OxcDiagnostic {
     )
     .with_label(span)
 }
+
+pub fn binding_element_export(span: Span) -> OxcDiagnostic {
+    OxcDiagnostic::error("Binding elements can't be exported directly with --isolatedDeclarations.")
+        .with_label(span)
+}

crates/oxc_isolated_declarations/tests/fixtures/non-exported-binding-elements.ts

@@ -0,0 +1,10 @@
+// Correct
+const [A, B] = [1, 2, 3];
+export function foo(): number {
+    return A;
+}
+
+// Incorrect
+const { c, d } = { c: 1, d: 2 };
+const [ e ] = [4];
+export { c, d, e }

crates/oxc_isolated_declarations/tests/snapshots/non-exported-binding-elements.snap

@@ -0,0 +1,35 @@
+---
+source: crates/oxc_isolated_declarations/tests/mod.rs
+input_file: crates/oxc_isolated_declarations/tests/fixtures/non-exported-binding-elements.ts
+---
+==================== .D.TS ====================
+
+export declare function foo(): number;
+export { c, d, e };
+
+
+==================== Errors ====================
+
+  x Binding elements can't be exported directly with --isolatedDeclarations.
+   ,-[8:9]
+ 7 | // Incorrect
+ 8 | const { c, d } = { c: 1, d: 2 };
+   :         ^
+ 9 | const [ e ] = [4];
+   `----
+
+  x Binding elements can't be exported directly with --isolatedDeclarations.
+   ,-[8:12]
+ 7 | // Incorrect
+ 8 | const { c, d } = { c: 1, d: 2 };
+   :            ^
+ 9 | const [ e ] = [4];
+   `----
+
+  x Binding elements can't be exported directly with --isolatedDeclarations.
+    ,-[9:9]
+  8 | const { c, d } = { c: 1, d: 2 };
+  9 | const [ e ] = [4];
+    :         ^
+ 10 | export { c, d, e }
+    `----