test(themes): E2E live skin switch — config write → skin.changed broadcast

tests/tui_gateway/test_protocol.py

@@ -2017,6 +2017,39 @@ def test_slow_completion_does_not_block_fast_handler(completion_method, server):
     released.set()
 
 
+def test_skin_live_switch_end_to_end(server, tmp_path, monkeypatch):
+    """Real config + skin files: activating a skin (as `hermes config set` does)
+    makes the per-tool reconcile broadcast skin.changed with the resolved palette.
+    Exercises _load_cfg → _skin_sig → resolve_skin → _emit with no mocks in between."""
+    import hermes_cli.skin_engine as skin_engine
+
+    (tmp_path / "skins").mkdir()
+    (tmp_path / "skins" / "midnight.yaml").write_text(
+        "name: midnight\ndescription: t\ncolors:\n  banner_title: '#00ffcc'\n  background: '#001010'\n"
+    )
+    monkeypatch.setattr(skin_engine, "get_hermes_home", lambda: tmp_path)
+    monkeypatch.setattr(server, "_hermes_home", tmp_path)
+    monkeypatch.setattr(server, "_last_skin_sig", None, raising=False)
+    server._cfg_cache = server._cfg_mtime = server._cfg_path = None
+
+    emitted = []
+    monkeypatch.setattr(server, "_emit", lambda ev, sid, payload=None: emitted.append((ev, payload)))
+
+    # Baseline (default) — seeds the signature.
+    (tmp_path / "config.yaml").write_text("display:\n  skin: default\n")
+    server._broadcast_skin_if_changed()
+    emitted.clear()
+
+    # Activate midnight, as `hermes config set display.skin midnight` would.
+    time.sleep(0.01)  # ensure the config mtime moves
+    (tmp_path / "config.yaml").write_text("display:\n  skin: midnight\n")
+    server._broadcast_skin_if_changed()
+
+    assert [ev for ev, _ in emitted] == ["skin.changed"]
+    assert emitted[0][1]["name"] == "midnight"
+    assert emitted[0][1]["colors"]["banner_title"] == "#00ffcc"
+
+
 def test_broadcast_skin_if_changed_on_any_signature_move(server, monkeypatch):
     """A skin the agent changes mid-turn goes live once per real move: a name
     switch (incl. switch-then-revert) OR an in-place color edit to the active skin