Close Campaign interface audit gaps

tests/test_mail_profile_boundary.py

@@ -7,6 +7,7 @@ import pytest
 from fastapi import HTTPException
 
 from govoplan_campaign.backend import route_support
+from govoplan_campaign.backend.routes import attachments as attachment_routes
 from govoplan_campaign.backend.routes import versions as router
 from govoplan_campaign.backend.campaign.loader import CampaignSchemaError, validate_against_schema
 from govoplan_campaign.backend.campaign.mail_profile_boundary import (
@@ -94,6 +95,42 @@ def test_loader_rejects_inline_transport_before_optional_mail_summary() -> None:
             )
 
 
+def test_attachment_preview_reports_legacy_mail_boundary_as_validation_error() -> None:
+    campaign = SimpleNamespace(id="campaign-1")
+    version = SimpleNamespace(
+        id="version-1",
+        campaign_id=campaign.id,
+        raw_json=_campaign_json({"smtp": {"host": "legacy.example.test"}}),
+    )
+    principal = SimpleNamespace(
+        tenant_id="tenant-1",
+        user=SimpleNamespace(id="user-1"),
+    )
+
+    with (
+        patch.object(attachment_routes, "_get_campaign_for_principal"),
+        patch.object(attachment_routes, "_require_permission"),
+        patch.object(attachment_routes, "_get_campaign_for_tenant", return_value=campaign),
+        patch.object(attachment_routes, "_get_version_for_tenant", return_value=version),
+        patch.object(attachment_routes, "_require_mail_profile_use_if_needed"),
+        patch.object(
+            attachment_routes,
+            "_attachment_preview_for_version",
+            side_effect=CampaignMailProfileBoundaryError("Select an authorized Mail profile."),
+        ),
+        pytest.raises(HTTPException) as captured,
+    ):
+        attachment_routes.preview_campaign_attachments(
+            campaign.id,
+            version.id,
+            session=object(),  # type: ignore[arg-type]
+            principal=principal,  # type: ignore[arg-type]
+        )
+
+    assert captured.value.status_code == 422
+    assert captured.value.detail == "Select an authorized Mail profile."
+
+
 def test_loader_uses_only_non_secret_mail_profile_capabilities() -> None:
     raw = _campaign_json({"mail_profile_id": "profile-1"})