Report a void property when Abri finds no tenancy for the place 🟥

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

domain/abri/models.py

@@ -108,7 +108,20 @@ class TenancyData:
     tenants: Tuple[Tenant, ...]
 
 
-GetTenantDataResult = Union[TenancyData, AbriRequestRejected]
+@dataclass(frozen=True)
+class NoTenancyFound:
+    """Abri reports no live tenancy for the place: the property is void.
+
+    Distinct from a TenancyData carrying no tenants (a tenancy exists, but
+    nobody is recorded against it) and from a rejection (the request itself
+    was refused). Only Abri's exact No_tenancy_found signal means this; the
+    query-dump variant of the same words is a genuine failure.
+    """
+
+    place_ref: PlaceRef
+
+
+GetTenantDataResult = Union[TenancyData, NoTenancyFound, AbriRequestRejected]
 
 
 @dataclass(frozen=True)

tests/abri/abri_relay_getscstenantdata_notenancyfound_response.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<response>
+    <success>false</success>
+    <code>RelayError</code>
+    <message>No_tenancy_found</message>
+</response>

tests/infrastructure/abri/test_abri_client.py

@@ -15,6 +15,7 @@ from domain.abri.models import (
     JobAbandoned,
     JobLogged,
     LogJobRequest,
+    NoTenancyFound,
     PlaceRef,
 )
 from infrastructure.abri.abri_client import AbriClient
@@ -556,3 +557,21 @@ def test_abandon_job_sends_the_recorded_canceljob_envelope_to_the_relay_endpoint
     assert ET.canonicalize(xml_data=sent_body, strip_text=True) == ET.canonicalize(
         xml_data=expected_body, strip_text=True
     )
+
+
+# --- get_tenant_data: a void property is not a rejection ---
+
+
+def test_get_tenant_data_reports_a_void_property_when_abri_finds_no_tenancy(
+    client: AbriClient, mock_session: MagicMock
+) -> None:
+    # Arrange: Abri's agreed signal that the place is known to be empty.
+    mock_session.post.return_value.content = _load_fixture(
+        "abri_relay_getscstenantdata_notenancyfound_response.xml"
+    )
+
+    # Act
+    result = client.get_tenant_data(PlaceRef("1004202A"))
+
+    # Assert
+    assert result == NoTenancyFound(place_ref=PlaceRef("1004202A"))