fix(image-gen): force-refresh plugin providers in long-lived sessions

tests/tools/test_image_generation_plugin_dispatch.py

@@ -0,0 +1,99 @@
+from __future__ import annotations
+
+import json
+import pytest
+
+from agent import image_gen_registry
+from agent.image_gen_provider import ImageGenProvider
+
+
+@pytest.fixture(autouse=True)
+def _reset_registry():
+    image_gen_registry._reset_for_tests()
+    yield
+    image_gen_registry._reset_for_tests()
+
+
+class _FakeCodexProvider(ImageGenProvider):
+    @property
+    def name(self) -> str:
+        return "codex"
+
+    def generate(self, prompt, aspect_ratio="landscape", **kwargs):
+        return {
+            "success": True,
+            "image": "/tmp/codex-test.png",
+            "model": "gpt-5.2-codex",
+            "prompt": prompt,
+            "aspect_ratio": aspect_ratio,
+            "provider": "codex",
+        }
+
+
+class TestPluginDispatch:
+    def test_dispatch_routes_to_codex_provider(self, monkeypatch, tmp_path):
+        from tools import image_generation_tool
+        from agent import image_gen_registry as registry_module
+        from hermes_cli import plugins as plugins_module
+
+        monkeypatch.setenv("HERMES_HOME", str(tmp_path))
+        (tmp_path / "config.yaml").write_text("image_gen:\n  provider: codex\n")
+        image_gen_registry.register_provider(_FakeCodexProvider())
+
+        monkeypatch.setattr(image_generation_tool, "_read_configured_image_provider", lambda: "codex")
+        monkeypatch.setattr(plugins_module, "_ensure_plugins_discovered", lambda: None)
+        monkeypatch.setattr(registry_module, "get_provider", lambda name: _FakeCodexProvider() if name == "codex" else None)
+
+        dispatched = image_generation_tool._dispatch_to_plugin_provider("draw cat", "square")
+        payload = json.loads(dispatched)
+
+        assert payload["success"] is True
+        assert payload["provider"] == "codex"
+        assert payload["image"] == "/tmp/codex-test.png"
+        assert payload["aspect_ratio"] == "square"
+
+    def test_dispatch_reports_missing_registered_provider(self, monkeypatch, tmp_path):
+        from tools import image_generation_tool
+        from hermes_cli import plugins as plugins_module
+
+        monkeypatch.setenv("HERMES_HOME", str(tmp_path))
+        (tmp_path / "config.yaml").write_text("image_gen:\n  provider: missing-codex\n")
+
+        monkeypatch.setattr(image_generation_tool, "_read_configured_image_provider", lambda: "missing-codex")
+        monkeypatch.setattr(plugins_module, "_ensure_plugins_discovered", lambda: None)
+
+        dispatched = image_generation_tool._dispatch_to_plugin_provider("draw cat", "landscape")
+        payload = json.loads(dispatched)
+
+        assert payload["success"] is False
+        assert payload["error_type"] == "provider_not_registered"
+        assert "image_gen.provider='missing-codex'" in payload["error"]
+
+    def test_dispatch_force_refreshes_plugins_when_provider_initially_missing(self, monkeypatch, tmp_path):
+        from tools import image_generation_tool
+        from hermes_cli import plugins as plugins_module
+        from agent import image_gen_registry as registry_module
+
+        monkeypatch.setenv("HERMES_HOME", str(tmp_path))
+        (tmp_path / "config.yaml").write_text("image_gen:\n  provider: codex\n")
+
+        monkeypatch.setattr(image_generation_tool, "_read_configured_image_provider", lambda: "codex")
+
+        calls = []
+        provider_state = {"provider": None}
+
+        def fake_ensure_plugins_discovered(force=False):
+            calls.append(force)
+            if force:
+                provider_state["provider"] = _FakeCodexProvider()
+
+        monkeypatch.setattr(plugins_module, "_ensure_plugins_discovered", fake_ensure_plugins_discovered)
+        monkeypatch.setattr(registry_module, "get_provider", lambda name: provider_state["provider"])
+
+        dispatched = image_generation_tool._dispatch_to_plugin_provider("draw hammy", "portrait")
+        payload = json.loads(dispatched)
+
+        assert calls == [False, True]
+        assert payload["success"] is True
+        assert payload["provider"] == "codex"
+        assert payload["aspect_ratio"] == "portrait"