feat(enemy): 选招器支持防重复折扣——WeightedRandomAntiRepeat

上一次选中的招按 EnemyStatsSO.attackAntiRepeatFactor 折扣权重（默认 0.3）。折扣把唯一候选压到 0 时退化为 Priority 路径，不会出现敌人永不出手。阶段切换清空防重复记忆。取代 BossBase.UseBossSkillWeighted 里的同名逻辑。 Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 12:43:01 +08:00
parent b0fd040904
commit eb3f4888a4
6 changed files with 132 additions and 12 deletions
@@ -104,5 +104,84 @@ namespace BaseGames.Tests.EditMode.Enemies
            for (int i = 0; i < 50; i++)
                Assert.AreSame(ok, Sel(bad, ok).Select(true, true, AttackSelectionMode.WeightedRandom));
        }
+
+        // ── WeightedRandomAntiRepeat ─────────────────────────────────────────
+
+        static EnemyAttackSelector SelAntiRepeat(float factor, params IAttackCandidate[] cs)
+            => new EnemyAttackSelector(new List<IAttackCandidate>(cs), factor);
+
+        [Test]
+        public void AntiRepeat_ZeroFactor_NeverPicksSameTwiceWhenAlternativeExists()
+        {
+            var a = new FakeCandidate { WeightV = 1f };
+            var b = new FakeCandidate { WeightV = 1f };
+            var s = SelAntiRepeat(0f, a, b);
+
+            var prev = s.Select(true, true, AttackSelectionMode.WeightedRandomAntiRepeat);
+            for (int i = 0; i < 100; i++)
+            {
+                var cur = s.Select(true, true, AttackSelectionMode.WeightedRandomAntiRepeat);
+                Assert.AreNotSame(prev, cur, "系数为 0 时不应连续选中同一招");
+                prev = cur;
+            }
+        }
+
+        [Test]
+        public void AntiRepeat_ZeroFactor_SingleCandidate_StillReturnsIt()
+        {
+            // 只有一招时折扣会把权重压到 0，WeightedPick 返回 -1；
+            // 必须退化为 Priority 路径把它选出来，否则敌人永远不出手。
+            var only = new FakeCandidate { WeightV = 1f };
+            var s = SelAntiRepeat(0f, only);
+
+            for (int i = 0; i < 10; i++)
+                Assert.AreSame(only, s.Select(true, true, AttackSelectionMode.WeightedRandomAntiRepeat));
+        }
+
+        [Test]
+        public void AntiRepeat_DiscountsPreviousPick_ButDoesNotBanIt()
+        {
+            // 系数 0.5：a 被选过后权重折半，但仍有机会再被选中。
+            var a = new FakeCandidate { WeightV = 1f };
+            var b = new FakeCandidate { WeightV = 1f };
+            var s = SelAntiRepeat(0.5f, a, b);
+
+            s.Select(true, true, AttackSelectionMode.WeightedRandomAntiRepeat);
+            int repeats = 0;
+            var prev = s.LastPicked;
+            for (int i = 0; i < 400; i++)
+            {
+                var cur = s.Select(true, true, AttackSelectionMode.WeightedRandomAntiRepeat);
+                if (ReferenceEquals(cur, prev)) repeats++;
+                prev = cur;
+            }
+            Assert.Greater(repeats, 0,   "折扣不应等于禁用");
+            Assert.Less   (repeats, 200, "折扣后重复率应低于无折扣时的约 50%");
+        }
+
+        [Test]
+        public void AntiRepeat_IneligiblePrevious_DoesNotBlockOthers()
+        {
+            var a = new FakeCandidate { WeightV = 1f };
+            var b = new FakeCandidate { WeightV = 1f };
+            var s = SelAntiRepeat(0f, a, b);
+
+            var first = s.Select(true, true, AttackSelectionMode.WeightedRandomAntiRepeat);
+            ((FakeCandidate)first).CanUseV = false;    // 上一招进冷却
+
+            var second = s.Select(true, true, AttackSelectionMode.WeightedRandomAntiRepeat);
+            Assert.IsNotNull(second);
+            Assert.AreNotSame(first, second);
+        }
+
+        [Test]
+        public void PlainWeighted_DoesNotApplyAntiRepeat()
+        {
+            // WeightedRandom 模式下唯一候选恒被选中（回归：折扣不得泄漏到旧模式）
+            var only = new FakeCandidate { WeightV = 1f };
+            var s = SelAntiRepeat(0f, only);
+            for (int i = 0; i < 10; i++)
+                Assert.AreSame(only, s.Select(true, true, AttackSelectionMode.WeightedRandom));
+        }
    }
 }