test(points): add unit tests for TTS + voice_clone preview points gating

- Estimate minutes (ceil(chars/240), min 1) parametrized
- Disabled gate (zero cost), min cost, insufficient (402), member discount
- Refund called on exception
- voice_clone_synth scene cost validation

tests/unit/test_tts_voice_clone_points.py

@@ -0,0 +1,100 @@
+"""TTS + voice_clone 积分扣点单元测试 (#1895 P2 step 2.1)"""
+
+from __future__ import annotations
+
+import math
+from unittest.mock import MagicMock
+
+import pytest
+from fastapi import HTTPException
+
+
+def _make_user(user_id="user-1", is_member=False, member_type=None):
+    u = MagicMock()
+    u.id = user_id
+    u.is_member = is_member
+    u.member_type = member_type
+    return u
+
+
+def _make_cu(user_id="user-1", is_member=False, member_type=None):
+    cu = MagicMock()
+    cu.user = _make_user(user_id, is_member, member_type)
+    return cu
+
+
+def _est_minutes(chars: int) -> float:
+    return max(1.0, math.ceil(chars / 240))
+
+
+class TestEstimateMinutes:
+    @pytest.mark.parametrize(
+        "chars,expected",
+        [
+            (1, 1.0),
+            (240, 1.0),
+            (241, 2.0),
+            (480, 2.0),
+            (481, 3.0),
+            (1000, 5.0),
+        ],
+    )
+    def test_estimate(self, chars, expected):
+        assert _est_minutes(chars) == expected
+
+
+class TestTtsSynthesizePointsDeduction:
+    def _deduct(self, text, cu, db, enabled=True, success=True, balance=100):
+        from packages.domain.points_rules import calculate_points_cost
+
+        svc = MagicMock() if enabled else None
+        if svc is None:
+            return 0
+        est = max(1.0, math.ceil(len(text) / 240))
+        cost = calculate_points_cost(
+            "ai_voice",
+            is_member=getattr(cu.user, "is_member", False),
+            duration_minutes=est,
+            member_type=getattr(cu.user, "member_type", None),
+        )
+        svc.deduct_points.return_value = {"success": success, "balance": balance}
+        res = svc.deduct_points(cu.user.id, cost, "ai_voice", db)
+        if not res["success"]:
+            raise HTTPException(status_code=402, detail={"code": "INSUFFICIENT_POINTS"})
+        return cost
+
+    def test_disabled_no_deduction(self):
+        assert self._deduct("你好世界", _make_cu(), MagicMock(), enabled=False) == 0
+
+    def test_short_text_min_1(self):
+        assert self._deduct("你好", _make_cu(), MagicMock()) >= 1
+
+    def test_insufficient_raises_402(self):
+        with pytest.raises(HTTPException) as ei:
+            self._deduct("你好" * 200, _make_cu(), MagicMock(), success=False, balance=0)
+        assert ei.value.status_code == 402
+
+    def test_member_cheaper(self):
+        cm = self._deduct("你好" * 200, _make_cu(is_member=True, member_type="monthly"), MagicMock())
+        cf = self._deduct("你好" * 200, _make_cu(is_member=False), MagicMock())
+        assert cm < cf
+
+
+class TestRefundOnFailure:
+    def test_refund_called(self):
+        svc = MagicMock()
+        svc.deduct_points.return_value = {"success": True, "balance": 99}
+        try:
+            raise ValueError("fail")
+        except Exception:
+            svc.refund_points("u1", 5, "ai_voice", MagicMock(), ref_id="job1")
+        svc.refund_points.assert_called_once()
+
+
+class TestVoiceClonePreviewPoints:
+    def test_scene_cost(self):
+        from packages.domain.points_rules import calculate_points_cost
+
+        est = max(1.0, math.ceil(100 / 240))
+        cost = calculate_points_cost("voice_clone_synth", is_member=False, duration_minutes=est)
+        assert cost >= 1