[Fix] export/TypeScript: properly detect export specifiers as children of a TS module block

Fixes import-js#1773

Author: Andreu Botella

CHANGELOG.md

@@ -10,6 +10,7 @@ This change log adheres to standards from [Keep a CHANGELOG](http://keepachangel
 - [`default`]/TypeScript: avoid crash on `export =` with a MemberExpression ([#1841], thanks [@ljharb])
 - [`extensions`]/importType: Fix @/abc being treated as scoped module ([#1854], thanks [@3nuc])
 - allow using rest operator in named export ([#1878], thanks [@foray1010])
+- [`export`]/TypeScript: properly detect export specifiers as children of a TS module block
 
 ### Changed
 - [`export`]: add tests for a name collision with `export * from` ([#1704], thanks @tomprats)

src/rules/export.js

@@ -87,7 +87,11 @@ module.exports = {
     return {
       'ExportDefaultDeclaration': (node) => addNamed('default', node, getParent(node)),
 
-      'ExportSpecifier': (node) => addNamed(node.exported.name, node.exported, getParent(node)),
+      'ExportSpecifier': (node) => addNamed(
+        node.exported.name,
+        node.exported,
+        getParent(node.parent)
+      ),
 
       'ExportNamedDeclaration': function (node) {
         if (node.declaration == null) return

tests/src/rules/export.js

@@ -221,6 +221,30 @@ context('TypeScript', function () {
             parser: parser,
           }),
         ]),
+
+        // Exports in ambient modules
+        test(Object.assign({
+          code: `
+            declare module "a" {
+              const Foo = 1;
+              export {Foo as default};
+            }
+            declare module "b" {
+              const Bar = 2;
+              export {Bar as default};
+            }
+          `,
+        }, parserConfig)),
+        test(Object.assign({
+          code: `
+            declare module "a" {
+              const Foo = 1;
+              export {Foo as default};
+            }
+            const Bar = 2;
+            export {Bar as default};
+          `,
+        }, parserConfig)),
       ],
       invalid: [
         // type/value name clash
@@ -312,6 +336,30 @@ context('TypeScript', function () {
             },
           ],
         }, parserConfig)),
+
+        // Exports in ambient modules
+        test(Object.assign({
+          code: `
+            declare module "a" {
+              const Foo = 1;
+              export {Foo as default};
+            }
+            const Bar = 2;
+            export {Bar as default};
+            const Baz = 3;
+            export {Baz as default};
+          `,
+          errors: [
+            {
+              message: 'Multiple default exports.',
+              line: 7,
+            },
+            {
+              message: 'Multiple default exports.',
+              line: 9,
+            },
+          ],
+        }, parserConfig)),
       ],
     })
   })