JS: Add JSDoc test case

Author: asgerf

javascript/ql/lib/semmle/javascript/internal/TypeResolution.qll

@@ -178,7 +178,7 @@ module TypeResolution {
     // Support JSDoc expressions of the form 'foo.bar' where 'foo' is an import
     // at the top-level.
     exists(JSDocNamedTypeExpr expr, string prefix |
-      expr.hasNameParts(prefix, name) and
+      expr.hasNameParts(prefix, "." + name) and
       node1 = expr.getTopLevel().getScope().getVariable(prefix) and
       node2 = expr
     )

javascript/ql/test/library-tests/UnderlyingTypes/jsdoc.js

@@ -0,0 +1,14 @@
+import * as e from 'express';
+import { Response } from 'express';
+
+/**
+ * @param {e.Request} req
+ */
+function t1(req) { // $ hasUnderlyingType='express'.Request SPURIOUS: hasUnderlyingType=e.Request
+}
+
+/**
+ * @param {Response} res
+ */
+function t2(res) { // $ MISSING: hasUnderlyingType='express'.Response SPURIOUS: hasUnderlyingType=Response
+}