zip/root isn't idempotent

[NoahTheDuke]

Version
1.1.48

Platform
Operating System: MacOS
Clojure version: 1.11.4
JDK vendor and version: openjdk 17.0.11 2024-04-16

Symptom
Can't call zip/root on a zipper multiple times.

Reproduction

(require '[rewrite-clj.zip :as zip])

(zip/root (zip/root (zip/of-string "a")))

Actual behavior
Throws a ClassCastException with message: "class rewrite_clj.node.forms.FormsNode cannot be cast to class clojure.lang.IFn (rewrite_clj.node.forms.FormsNode is in unnamed module of loader clojure.lang.DynamicClassLoader @653a5a; clojure.lang.IFn is in unnamed module of loader 'app')"

Expected behavior
I would expect that zip/root is idempotent and can be called repeatedly on a zipper.

Diagnosis
I haven't looked at the code yet, so I'm not sure.

Action
Wait and see.

[NoahTheDuke]

Having written all that out, I see that the docstring says that zip/root returns a node, not a zipper? How do you traverse to the root of the zipper?

[lread]

I'm not crazy about the naming of the zip/root fn.
But it comes from clojure.zip (which uses terminology from Huet's Zipper paper), so we'll keep using it.
As you've noticed it does not return a zipper, it returns the root node with all changes applied.

There is an open issue about traversing to the top node #149.
If you are still stuck, leave another comment.

[lread]

@NoahTheDuke, is this issue good to close now?
Or do you think we should discuss more?

[lread]

Chatted with @NoahTheDuke, he's good to close this one.