Duplicate a unit: describe the furniture once, stamp out the rest

Eric's ask. duplicate-unit clones the STRUCTURE — openings with their
sizes, zones, and descriptions, under fresh ids and the first free
"<name> 2"-style name — never the game assignments. And because a
copy immediately wants a real name, units gained rename: opening ids
are stable through it so locations and export URLs never notice, and
a rename-only edit no longer risks wiping the description (the body
field learned the None-means-leave-alone convention). Tests pin the
disjoint ids, the empty copy, the numbering past taken names, and
the wipe-nothing rename.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016jXZFSTZQKzAC8fqpWSz9g

tests/test_shelves.py

@@ -875,3 +875,106 @@ def test_unit_descriptions_round_trip(tmp_path):
 
     saved = _json.loads(cfg.furniture_path.read_text())["units"][0]
     assert saved["description"] == "now in the study"
+
+
+def test_duplicate_unit_copies_structure_never_games(tmp_path):
+    games = {
+        "1": {
+            "bgg_id": 1,
+            "name": "Catan",
+            "dims": {
+                "width_in": 11,
+                "length_in": 11,
+                "depth_in": 3,
+                "source": "version",
+            },
+        }
+    }
+    web, cfg = _web(tmp_path, games)
+    web.post(
+        "/api/furniture/add-unit",
+        json={"name": "Kallax", "description": "the original"},
+    )
+    web.post(
+        "/api/furniture/add-openings",
+        json={
+            "unit": "Kallax",
+            "rows": 1,
+            "cols": 2,
+            "zone": "cubes",
+            "width_in": 13.25,
+            "height_in": 13.25,
+            "depth_in": 15.4,
+        },
+    )
+    first = web.get("/api/shelves").json()["units"][0]["openings"][0]["id"]
+    web.post(
+        "/api/furniture/edit-opening", json={"id": first, "description": "top left"}
+    )
+    web.post("/api/locate", json={"key": "1", "opening_id": first})
+
+    web.post("/api/furniture/duplicate-unit", json={"name": "Kallax"})
+    state = web.get("/api/shelves").json()
+    names = [u["name"] for u in state["units"]]
+    assert names == ["Kallax", "Kallax 2"]
+    copy = state["units"][1]
+    assert copy["description"] == "the original"
+    assert [o["label"] for o in copy["openings"]] == ["A1", "A2"]
+    assert copy["openings"][0]["description"] == "top left"
+    # fresh ids, no residents copied
+    original_ids = {o["id"] for o in state["units"][0]["openings"]}
+    copy_ids = {o["id"] for o in copy["openings"]}
+    assert original_ids.isdisjoint(copy_ids)
+    assert all(o["games"] == 0 for o in copy["openings"])
+    # duplicating again numbers past the taken name
+    web.post("/api/furniture/duplicate-unit", json={"name": "Kallax"})
+    names = [u["name"] for u in web.get("/api/shelves").json()["units"]]
+    assert names == ["Kallax", "Kallax 2", "Kallax 3"]
+
+
+def test_rename_unit_keeps_openings_locations_and_description(tmp_path):
+    games = {
+        "1": {
+            "bgg_id": 1,
+            "name": "Catan",
+            "dims": {
+                "width_in": 11,
+                "length_in": 11,
+                "depth_in": 3,
+                "source": "version",
+            },
+        }
+    }
+    web, cfg = _web(tmp_path, games)
+    web.post(
+        "/api/furniture/add-unit", json={"name": "Kallax", "description": "keep me"}
+    )
+    web.post(
+        "/api/furniture/add-openings",
+        json={
+            "unit": "Kallax",
+            "label": "A1",
+            "width_in": 13.25,
+            "height_in": 13.25,
+            "depth_in": 15.4,
+        },
+    )
+    oid = web.get("/api/shelves").json()["units"][0]["openings"][0]["id"]
+    web.post("/api/locate", json={"key": "1", "opening_id": oid})
+    web.post(
+        "/api/furniture/edit-unit", json={"name": "Kallax", "new_name": "Den wall"}
+    )
+    state = web.get("/api/shelves").json()
+    unit = state["units"][0]
+    assert unit["name"] == "Den wall"
+    assert unit["description"] == "keep me"  # rename-only edit wipes nothing
+    assert unit["openings"][0]["games"] == 1  # opening ids stable: game stays
+    # rename onto a taken name refuses
+    web.post("/api/furniture/add-unit", json={"name": "Loft"})
+    assert (
+        web.post(
+            "/api/furniture/edit-unit",
+            json={"name": "Den wall", "new_name": "Loft"},
+        ).status_code
+        == 409
+    )