MAS-WP-0005-T02: SCP-1 quoted local-parts equivalent on receipt

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 252470@bnt-lap001
Assistant-Session: ad628c8f-4be2-4979-94c9-76c7ed6f8241

tests/test_end_to_end.py

@@ -130,8 +130,12 @@ def test_unconfirmed_namespace_is_not_acted_on(env):
 
 def test_non_mas_recipient_still_forwarded(env):
     _, _, _, resolver = env
-    ev = build_event(f'"quoted"@{D}', {}, resolver)
-    assert ev["mas"]["valid"] is False and ev["recipient"] == f'"quoted"@{D}'
+    ev = build_event(f'"not mas"@{D}', {}, resolver)
+    assert ev["mas"]["valid"] is False and ev["recipient"] == f'"not mas"@{D}'
+    # SCP-1: unnecessary quotes are equivalent to the unquoted form
+    ev = build_event(f'"ticket=GS-1"@{D}', {}, resolver)
+    assert ev["mas"]["valid"] is True and ev["mas"]["equivalence_key"] == "ticket=GS-1"
+    assert ev["recipient"] == f'"ticket=GS-1"@{D}'   # the event keeps what arrived
 
 
 def test_pipe_transport_subprocess(env):

tests/test_parser_conformance.py

@@ -12,6 +12,7 @@ from mas_core.parser import (
     MasSyntaxError,
     parse_address,
     parse_local_part,
+    parse_received_address,
     validate_profile,
 )
 
@@ -111,3 +112,23 @@ def test_generator_rules():
             p = parse_local_part(f["local_part"])
             with pytest.raises(MasSyntaxError):
                 generate_local_part(str(p.target), facet=p.facet.value, interaction=p.interaction.mode)
+
+
+@pytest.mark.parametrize("raw, expected", [
+    ('"ticket=PR42"@example.com', "ticket=PR42"),        # SCP-1: unnecessary quotes
+    ('"ticket!callback"@example.com', "ticket!callback"),
+    ("ticket=PR42@example.com", "ticket=PR42"),
+])
+def test_received_quoted_local_part_is_equivalent(raw, expected):
+    assert parse_received_address(raw).local.raw == expected
+
+
+@pytest.mark.parametrize("raw", ['"a\\"b"@example.com', '"a b"@example.com', '"x@y"@example.com'])
+def test_received_quoted_non_mas_stays_invalid(raw):
+    with pytest.raises(MasSyntaxError):
+        parse_received_address(raw)
+
+
+def test_canonical_parser_still_rejects_quotes():
+    with pytest.raises(MasSyntaxError):
+        parse_address('"ticket=PR42"@example.com')