TIER-2 READ conductor/code_styleguides/error_handling.md end-to-end before Phase 5: refactor(gui_2): migrate L5380 render_operations_hub ext_editor_panel to Result[T] (Phase 5)

Extract _render_operations_hub_external_editor_panel_result helper from the
render_external_editor_panel call try/except in render_operations_hub
External Tools tab. Legacy wrapper drains errors to app._last_request_errors
per FR-BC-4 event-handler pattern.

[pre-audit] L5380 INTERNAL_BROAD_CATCH
[post-audit] V count: 7 -> 6 (L5380 removed)

src/gui_2.py

@@ -5333,8 +5333,11 @@ def render_operations_hub(app: App) -> None:
     if exp:
      render_external_tools_panel(app)
      imgui.separator(); imgui.text("")
-     try: render_external_editor_panel(app)
-     except Exception as e: imgui.text_colored(theme.get_color("status_error"), f"Error: {str(e)}")
+     ext_panel_result = _render_operations_hub_external_editor_panel_result(app)
+     if not ext_panel_result.ok:
+      if not hasattr(app, '_last_request_errors'): app._last_request_errors = []
+      app._last_request_errors.append(("_render_operations_hub_external_editor_panel", ext_panel_result.errors[0]))
+      imgui.text_colored(theme.get_color("status_error"), f"Error: {ext_panel_result.errors[0].message}")
   with imscope.tab_item("Workspace Layouts") as (exp, _):
    if exp:
     imgui.text("Experimental: Auto-switch layout by Tier")
@@ -7960,6 +7963,31 @@ def _render_context_batch_actions_preview_result(app: "App") -> Result[str]:
    original=e,
   )])
 
+
+def _render_operations_hub_external_editor_panel_result(app: "App") -> Result[bool]:
+ """Drain-aware variant of L5380 render_operations_hub External Tools tab.
+
+ Extracts the render_external_editor_panel call try/except from
+ render_operations_hub External Tools tab into a Result-returning helper.
+ On success, returns Result(data=True). On exception, converts the
+ exception to ErrorInfo and returns Result(data=False, errors=[ErrorInfo]).
+
+ The legacy wrapper drains errors to app._last_request_errors (per FR-BC-4
+ event-handler drain pattern; data plane attribute).
+
+ [C: src/gui_2.py:render_operations_hub (L5380 legacy wrapper)]
+ """
+ try:
+  render_external_editor_panel(app)
+  return Result(data=True)
+ except Exception as e:
+  return Result(data=False, errors=[ErrorInfo(
+   kind=ErrorKind.INTERNAL,
+   message=f"Render external editor panel from operations hub failed: {e}",
+   source="gui_2._render_operations_hub_external_editor_panel_result",
+   original=e,
+  )])
+
 #endregion: Phase 5 Event Handler Result Helpers
 
 #endregion: MMA

tests/test_gui_2_result.py

@@ -1107,3 +1107,38 @@ def test_phase_5_l3582_render_context_batch_actions_preview_result_failure():
  assert err.source == "gui_2._render_context_batch_actions_preview_result"
  assert "generate failed" in err.message
  assert "Error" in result.data
+
+
+def test_phase_5_l5380_render_operations_hub_external_editor_panel_result_success():
+ """
+ L5380 _render_operations_hub_external_editor_panel_result returns Result.ok=True on success.
+
+ The helper wraps the render_external_editor_panel call within render_operations_hub
+ External Tools tab try/except. On success, returns Result(data=True).
+ """
+ from src import gui_2
+ from unittest.mock import MagicMock, patch
+ app = MagicMock()
+ with patch.object(gui_2, "render_external_editor_panel"):
+  result = gui_2._render_operations_hub_external_editor_panel_result(app)
+ assert result.ok, f"Expected ok=True on success, got errors: {result.errors}"
+ assert result.data is True
+
+
+def test_phase_5_l5380_render_operations_hub_external_editor_panel_result_failure():
+ """
+ L5380 _render_operations_hub_external_editor_panel_result returns Result.ok=False on failure.
+
+ When render_external_editor_panel raises, the helper converts the exception
+ to ErrorInfo and returns Result(data=False, errors=[ErrorInfo]).
+ """
+ from src import gui_2
+ from unittest.mock import MagicMock, patch
+ app = MagicMock()
+ with patch.object(gui_2, "render_external_editor_panel", side_effect=RuntimeError("ext editor render blew up")):
+  result = gui_2._render_operations_hub_external_editor_panel_result(app)
+ assert not result.ok, f"Expected ok=False on failure, got data: {result.data}"
+ assert result.errors, "Expected at least one error on failure"
+ err = result.errors[0]
+ assert err.source == "gui_2._render_operations_hub_external_editor_panel_result"
+ assert "ext editor render blew up" in err.message