Add support for importing NPM modules in XSJS sources

javascript/ql/lib/semmle/javascript/NodeJS.qll

@@ -295,6 +295,15 @@ private predicate isRequire(DataFlow::Node nd) {
     isCreateRequire(call.getCallee().flow()) and
     nd = call.flow()
   )
+  or
+  // `$.require('underscore');`.
+  // NPM as supported in [XSJS files](https://www.npmjs.com/package/@sap/async-xsjs#npm-packages-support).
+  exists(MethodCallExpr require |
+    nd.getFile().getExtension() = ["xsjs", "xsjslib"] and
+    require.getCalleeName() = "require" and
+    require.getReceiver().(GlobalVarAccess).getName() = "$" and
+    nd = require.getCallee().flow()
+  )
 }
 
 /**