Fix crash when converting undefined default export

Closes #2175
Closes #2176

Co-Authored-By: Remi Cattiau <remi@cattiau.com>

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Unreleased
 
+### Bug Fixes
+
+-   Fix crash when converting `export default undefined`, #2175
+
+### Thanks!
+
+-   @loopingz
+
 ## v0.23.25 (2023-02-11)
 
 ### Breaking Changes

src/lib/converter/comments/index.ts

@@ -103,13 +103,14 @@ export function getComment(
     logger: Logger,
     commentStyle: CommentStyle
 ): Comment | undefined {
+    const declarations = symbol.declarations || [];
+
     if (
-        symbol
-            .getDeclarations()
-            ?.every((d) => jsDocCommentKinds.includes(d.kind))
+        declarations.length &&
+        declarations.every((d) => jsDocCommentKinds.includes(d.kind))
     ) {
         return getJsDocComment(
-            symbol.declarations![0] as ts.JSDocPropertyLikeTag,
+            declarations[0] as ts.JSDocPropertyLikeTag,
             config,
             logger
         );
@@ -119,7 +120,7 @@ export function getComment(
         discoverComment(symbol, kind, logger, commentStyle),
         config,
         logger,
-        symbol.declarations?.some(ts.isSourceFile) || false
+        declarations.some(ts.isSourceFile)
     );
 
     if (!comment && kind === ReflectionKind.Property) {

src/test/converter2/issues/gh2175.ts

@@ -0,0 +1,5 @@
+/**
+ * `undefined` is special in that it has no declarations, so we can have
+ * an export without any declarations so long as it is undefined.
+ */
+export default undefined;

src/test/issueTests.ts

@@ -848,4 +848,10 @@ export const issueTests: {
             "Is documented"
         );
     },
+
+    gh2175(project) {
+        const def = query(project, "default");
+        equal(def.type?.type, "intrinsic");
+        equal(def.type.toString(), "undefined");
+    },
 };