Fix panic when @callback/@overload @param has a qualified name

internal/parser/reparser.go

@@ -135,6 +135,11 @@ func (p *Parser) reparseJSDocSignature(jsSignature *ast.Node, fun *ast.Node, jsD
 			}
 		} else if param.Kind == ast.KindJSDocParameterTag || param.Kind == ast.KindJSDocPropertyTag {
 			jsparam := param.AsJSDocParameterOrPropertyTag()
+			// Skip sub-property parameters (e.g., @param x.y) - these have QualifiedNames
+			// and describe properties of a parent parameter, not standalone parameters.
+			if ast.IsQualifiedName(jsparam.Name()) {
+				continue
+			}
 			var dotDotDotToken *ast.Node
 			var paramType *ast.TypeNode
 

testdata/baselines/reference/compiler/jsdocCallbackParamQualifiedName.errors.txt

@@ -0,0 +1,31 @@
+bug.js(23,14): error TS2339: Property 'y' does not exist on type 'object'.
+
+
+==== bug.js (1 errors) ====
+    /**
+     * @callback cb
+     * @param x.y
+     */
+
+    /**
+     * @callback cb2
+     * @param {object} x
+     * @param {string} x.y
+     */
+
+    /**
+     * @overload
+     * @param {object} x
+     * @param {string} x.y
+     * @returns {string}
+     */
+    /**
+     * @param {object} x
+     * @returns {string}
+     */
+    function foo(x) {
+        return x.y;
+                 ~
+!!! error TS2339: Property 'y' does not exist on type 'object'.
+    }
+

testdata/baselines/reference/compiler/jsdocCallbackParamQualifiedName.symbols

@@ -0,0 +1,32 @@
+//// [tests/cases/compiler/jsdocCallbackParamQualifiedName.ts] ////
+
+=== bug.js ===
+/**
+ * @callback cb
+ * @param x.y
+ */
+
+/**
+ * @callback cb2
+ * @param {object} x
+ * @param {string} x.y
+ */
+
+/**
+ * @overload
+ * @param {object} x
+ * @param {string} x.y
+ * @returns {string}
+ */
+/**
+ * @param {object} x
+ * @returns {string}
+ */
+function foo(x) {
+>foo : Symbol(foo, Decl(bug.js, 12, 4), Decl(bug.js, 0, 0))
+>x : Symbol(x, Decl(bug.js, 21, 13))
+
+    return x.y;
+>x : Symbol(x, Decl(bug.js, 21, 13))
+}
+

testdata/baselines/reference/compiler/jsdocCallbackParamQualifiedName.types

@@ -0,0 +1,34 @@
+//// [tests/cases/compiler/jsdocCallbackParamQualifiedName.ts] ////
+
+=== bug.js ===
+/**
+ * @callback cb
+ * @param x.y
+ */
+
+/**
+ * @callback cb2
+ * @param {object} x
+ * @param {string} x.y
+ */
+
+/**
+ * @overload
+ * @param {object} x
+ * @param {string} x.y
+ * @returns {string}
+ */
+/**
+ * @param {object} x
+ * @returns {string}
+ */
+function foo(x) {
+>foo : (x: { y: string; }) => string
+>x : object
+
+    return x.y;
+>x.y : any
+>x : object
+>y : any
+}
+

testdata/tests/cases/compiler/jsdocCallbackParamQualifiedName.ts

@@ -0,0 +1,29 @@
+// @allowJs: true
+// @checkJs: true
+// @noEmit: true
+
+// @filename: bug.js
+/**
+ * @callback cb
+ * @param x.y
+ */
+
+/**
+ * @callback cb2
+ * @param {object} x
+ * @param {string} x.y
+ */
+
+/**
+ * @overload
+ * @param {object} x
+ * @param {string} x.y
+ * @returns {string}
+ */
+/**
+ * @param {object} x
+ * @returns {string}
+ */
+function foo(x) {
+    return x.y;
+}