Handle numeric literal export names in declaration emit (#3919)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: jakebailey <5341706+jakebailey@users.noreply.github.com>

Author: Copilot

internal/transformers/declarations/transform.go

@@ -2174,6 +2174,10 @@ func (tx *DeclarationTransformer) transformJSDocOptionalType(input *ast.JSDocOpt
 }
 
 func (tx *DeclarationTransformer) getNameExpressionPreferringIdentifier(nameExpr *ast.Node) *ast.Node {
+	if ast.IsNumericLiteral(nameExpr) {
+		// Numeric property names are string properties in JS; convert to string literal
+		nameExpr = tx.Factory().NewStringLiteral(nameExpr.Text(), ast.TokenFlagsNone)
+	}
 	if ast.IsStringLiteralLike(nameExpr) && scanner.IsIdentifierText(nameExpr.Text(), core.LanguageVariantStandard) {
 		result := tx.Factory().NewIdentifier(nameExpr.Text()) // prefer non-string literal names where possible
 		kwKind := scanner.IdentifierToKeywordKind(result.AsIdentifier())

testdata/baselines/reference/compiler/numericExportNameDeclaration.js

@@ -0,0 +1,41 @@
+//// [tests/cases/compiler/numericExportNameDeclaration.ts] ////
+
+//// [bug.js]
+exports[1] = 2;
+module.exports[1] = 2;
+Object.defineProperty(exports, 1, {});
+
+
+
+
+//// [bug.d.ts]
+declare const _exported: any;
+export { _exported as "1" };
+declare const _exported_1: any;
+export { _exported_1 as "1" };
+declare const _exported_2: any;
+export { _exported_2 as "1" };
+
+
+//// [DtsFileErrors]
+
+
+bug.d.ts(2,23): error TS2300: Duplicate identifier '"1"'.
+bug.d.ts(4,25): error TS2300: Duplicate identifier '"1"'.
+bug.d.ts(6,25): error TS2300: Duplicate identifier '"1"'.
+
+
+==== bug.d.ts (3 errors) ====
+    declare const _exported: any;
+    export { _exported as "1" };
+                          ~~~
+!!! error TS2300: Duplicate identifier '"1"'.
+    declare const _exported_1: any;
+    export { _exported_1 as "1" };
+                            ~~~
+!!! error TS2300: Duplicate identifier '"1"'.
+    declare const _exported_2: any;
+    export { _exported_2 as "1" };
+                            ~~~
+!!! error TS2300: Duplicate identifier '"1"'.
+    

testdata/baselines/reference/compiler/numericExportNameDeclaration.symbols

@@ -0,0 +1,19 @@
+//// [tests/cases/compiler/numericExportNameDeclaration.ts] ////
+
+=== bug.js ===
+exports[1] = 2;
+>exports : Symbol(exports, Decl(bug.js, 0, 0))
+>1 : Symbol(1, Decl(bug.js, 0, 0), Decl(bug.js, 0, 15), Decl(bug.js, 1, 22))
+
+module.exports[1] = 2;
+>module.exports : Symbol(exports, Decl(bug.js, 0, 0))
+>module : Symbol(module, Decl(bug.js, 0, 0))
+>exports : Symbol(exports, Decl(bug.js, 0, 0))
+>1 : Symbol(1, Decl(bug.js, 0, 0), Decl(bug.js, 0, 15), Decl(bug.js, 1, 22))
+
+Object.defineProperty(exports, 1, {});
+>Object.defineProperty : Symbol(ObjectConstructor.defineProperty, Decl(lib.es5.d.ts, --, --))
+>Object : Symbol(Object, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>defineProperty : Symbol(ObjectConstructor.defineProperty, Decl(lib.es5.d.ts, --, --))
+>exports : Symbol(exports, Decl(bug.js, 0, 0))
+

testdata/baselines/reference/compiler/numericExportNameDeclaration.types

@@ -0,0 +1,28 @@
+//// [tests/cases/compiler/numericExportNameDeclaration.ts] ////
+
+=== bug.js ===
+exports[1] = 2;
+>exports[1] = 2 : 2
+>exports[1] : any
+>exports : typeof import("./bug")
+>1 : 1
+>2 : 2
+
+module.exports[1] = 2;
+>module.exports[1] = 2 : 2
+>module.exports[1] : error
+>module.exports : typeof import("./bug")
+>module : { exports: typeof import("./bug"); }
+>exports : typeof import("./bug")
+>1 : 1
+>2 : 2
+
+Object.defineProperty(exports, 1, {});
+>Object.defineProperty(exports, 1, {}) : typeof import("./bug")
+>Object.defineProperty : <T>(o: T, p: PropertyKey, attributes: PropertyDescriptor & ThisType<any>) => T
+>Object : ObjectConstructor
+>defineProperty : <T>(o: T, p: PropertyKey, attributes: PropertyDescriptor & ThisType<any>) => T
+>exports : typeof import("./bug")
+>1 : 1
+>{} : {}
+

testdata/tests/cases/compiler/numericExportNameDeclaration.ts

@@ -0,0 +1,8 @@
+// @declaration: true
+// @emitDeclarationOnly: true
+// @allowJs: true
+
+// @filename: bug.js
+exports[1] = 2;
+module.exports[1] = 2;
+Object.defineProperty(exports, 1, {});