fix(tests): F2 — the voluptuous mirror compares fields, not marker classes (t35)

real voluptuous 0.16.0 implements ``Marker.__eq__`` as ``self.schema ==
other`` — a field-name comparison with no class check, so
``Optional("x") == Required("x")`` is True (verified against the library
source, not just the audit note). The mirror compared class + field, which
kept two dict entries for one field: a ``Required(field, default=...)`` after
``Optional(field)`` LOOKED like it applied the default, while real voluptuous
keeps the first (defaultless) key object and silently drops it — the exact
t33 F-A failure mode the mirror exists to catch, i.e. the harness could mask
the bug it was built to see.

``Marker.__eq__`` is now the library's comparison and the contract tests gained
both pins: field-only equality (with equal hashes) and the mixed-marker
re-declaration that used to be masked. Reverting only ``__eq__`` makes those
two fail, which is the red proof recorded for t35.

Verified: uvx --with pytest-asyncio pytest tests -q → 276 passed, 1 skipped;
uvx ruff check custom_components tests → clean.

tests/test_config_flow_ux.py

@@ -424,6 +424,37 @@ class TestVoluptuousMirrorContract:
             vol_mirror.declared_fields({CONF_ADB_HOST: str})
 
 
+    def test_marker_equality_is_field_only_like_voluptuous(self):
+        """t35 F2: real ``Marker.__eq__`` is ``self.schema == other``.
+
+        No class check: ``Optional("x") == Required("x")`` on voluptuous 0.16.0.
+        """
+        vol = sys.modules["voluptuous"]
+
+        assert vol.Optional(CONF_ADB_HOST) == vol.Required(CONF_ADB_HOST)
+        assert hash(vol.Optional(CONF_ADB_HOST)) == hash(
+            vol.Required(CONF_ADB_HOST)
+        )
+        # the real implementation compares the field name to the other value
+        assert vol.Optional(CONF_ADB_HOST) == CONF_ADB_HOST
+
+    def test_a_mixed_marker_redeclaration_drops_the_default(self):
+        """The case a class-comparing mirror masks (t35 F2).
+
+        ``Required(field, default=...)`` after ``Optional(field)`` collides on
+        the field name, so the FIRST key object (no default) survives — the
+        schema silently loses the default, exactly like the Optional case.
+        """
+        vol = sys.modules["voluptuous"]
+        schema = {vol.Optional(CONF_ADB_HOST): str}
+        schema[vol.Required(CONF_ADB_HOST, default=DISCOVERED_HOST)] = str
+
+        assert (
+            vol_mirror.defaults_by_key(schema)[CONF_ADB_HOST]
+            is vol_mirror.UNDEFINED
+        )
+
+
 class TestDiscoveryPrefill:
     """F-A / F-A2 / F-D: the discovered address reaches the rendered FORM."""
 

tests/voluptuous_mirror.py

@@ -6,10 +6,12 @@ behaviours the flow schemas depend on:
 
 * ``Optional(field, default=value)`` / ``Required(field, default=value)`` carry
   that default on the KEY object;
-* keys compare by FIELD NAME only — real ``voluptuous.Marker`` implements
-  ``__hash__ = hash(self.schema)`` and ``__eq__`` on class + schema. A later
-  re-declaration of the same field therefore keeps the FIRST key object, so a
-  default added by a second declaration is silently dropped.
+* keys compare by FIELD NAME only — real ``voluptuous.Marker.__eq__`` is
+  ``self.schema == other`` (no class check at all), so
+  ``Optional("x") == Required("x")`` is True, and ``__hash__`` is
+  ``hash(self.schema)``. A later re-declaration of the same field therefore
+  collides with the FIRST key object, so a default added by a second
+  declaration is silently dropped.
 
 That second property is exactly how the t33 F-A discovery-prefill bug hid from
 the suite: the old stubs reduced every key to its bare string, so a schema
@@ -37,8 +39,11 @@ class Marker:
         return hash(self.schema)
 
     def __eq__(self, other):
-        # real Marker compares class + field name, never the default
-        return type(other) is type(self) and other.schema == self.schema
+        # real Marker.__eq__ is `self.schema == other`: the FIELD is the whole
+        # comparison — no class check, so Optional("x") == Required("x") (and
+        # even Marker("x") == "x") is True. That is what makes a re-declaration
+        # of a field collide with the first key object and drop its default.
+        return self.schema == other
 
     def __repr__(self):
         return f"<{type(self).__name__} {self.schema!r} default={self.default!r}>"