refactor: Move legacy deserialization into the .Migrations.cs partials (#2575)

Follow-up to #2574, which added a `.Migrations.cs` partial to `BaseWeapon`. Pure relocation — no behaviour change.

## The inconsistency

`BaseArmor` and `BaseClothing` already kept their pre-codegen `Deserialize(reader, version)` in a `.Migrations.cs` partial, but left the `OldSaveFlag` enum and the `GetSaveFlag` helper behind in the main class file — even though every call site is in the partial:

| Class | `Deserialize` | `GetSaveFlag` / `OldSaveFlag` | Call sites outside the partial |
|---|---|---|---|
| `BaseArmor` | already in partial | in main file | 0 of 26 |
| `BaseClothing` | already in partial | in main file | 0 of 12 |
| `BaseWeapon` | in main file | in main file | — |

`BaseWeapon` had all three still inline, with its new `.Migrations.cs` holding only a `MigrateFrom`.

## After

All three follow the same layout: `MigrateFrom` newest to oldest, then the pre-codegen `Deserialize`, then `GetSaveFlag`, then `OldSaveFlag`. That moves ~290 lines of legacy read path out of `BaseWeapon.cs` — the file that needed it most at ~3,900 lines — and leaves the main class files describing only how the type behaves today.

## Reviewing this

The diff is large and almost entirely noise, so it is probably not worth reading line by line. Two checks are stronger:

- **Nothing was lost or altered.** Across each `.cs` / `.Migrations.cs` pair, the multiset of non-blank source lines is identical to `main` except for one added comment (below). The relocation was done mechanically and asserted against that invariant rather than by hand.
- **Nothing about serialization moved with the code.** Running `ModernUOSchemaGenerator` after the move emits no new migration files.

The complete set of intentional additions:

- `using System;` in each of the three partials, for the `[Flags]` attribute (implicit usings are not enabled here).
- `// Version 9 (pre-codegen)` above `BaseWeapon`'s moved `Deserialize`, matching the marker `BaseArmor` and `BaseClothing` already carry. Version 9 is correct because `BaseWeapon.v10.json` is its earliest migration schema, so codegen began at 10.

Everything else is blank-line placement.

## Verification

Full solution builds in Release with 0 errors and 0 warnings; 1516 tests pass (815 `Server.Tests`, 701 `UOContent.Tests`).

Projects/UOContent/Items/Armor/BaseArmor.Migrations.cs

@@ -1,3 +1,4 @@
+using System;
 using AMA = Server.Items.ArmorMeditationAllowance;
 
 namespace Server.Items;
@@ -192,4 +193,37 @@ public partial class BaseArmor
 
         PlayerConstructed = GetSaveFlag(flags, OldSaveFlag.PlayerConstructed);
     }
+
+    private static bool GetSaveFlag(OldSaveFlag flags, OldSaveFlag toGet) => (flags & toGet) != 0;
+
+    [Flags]
+    private enum OldSaveFlag
+    {
+        None = 0x00000000,
+        Attributes = 0x00000001,
+        ArmorAttributes = 0x00000002,
+        PhysicalBonus = 0x00000004,
+        FireBonus = 0x00000008,
+        ColdBonus = 0x00000010,
+        PoisonBonus = 0x00000020,
+        EnergyBonus = 0x00000040,
+        Identified = 0x00000080,
+        MaxHitPoints = 0x00000100,
+        HitPoints = 0x00000200,
+        Crafter = 0x00000400,
+        Quality = 0x00000800,
+        Durability = 0x00001000,
+        Protection = 0x00002000,
+        Resource = 0x00004000,
+        BaseArmor = 0x00008000,
+        StrBonus = 0x00010000,
+        DexBonus = 0x00020000,
+        IntBonus = 0x00040000,
+        StrReq = 0x00080000,
+        DexReq = 0x00100000,
+        IntReq = 0x00200000,
+        MedAllowance = 0x00400000,
+        SkillBonuses = 0x00800000,
+        PlayerConstructed = 0x01000000
+    }
 }

Projects/UOContent/Items/Armor/BaseArmor.cs

@@ -1018,8 +1018,6 @@ namespace Server.Items
             (Parent as Mobile)?.Delta(MobileDelta.Armor); // Tell them armor rating has changed
         }
 
-        private static bool GetSaveFlag(OldSaveFlag flags, OldSaveFlag toGet) => (flags & toGet) != 0;
-
         [AfterDeserialization]
         private void AfterDeserialization()
         {
@@ -1506,35 +1504,5 @@ namespace Server.Items
                 };
         }
 
-        [Flags]
-        private enum OldSaveFlag
-        {
-            None = 0x00000000,
-            Attributes = 0x00000001,
-            ArmorAttributes = 0x00000002,
-            PhysicalBonus = 0x00000004,
-            FireBonus = 0x00000008,
-            ColdBonus = 0x00000010,
-            PoisonBonus = 0x00000020,
-            EnergyBonus = 0x00000040,
-            Identified = 0x00000080,
-            MaxHitPoints = 0x00000100,
-            HitPoints = 0x00000200,
-            Crafter = 0x00000400,
-            Quality = 0x00000800,
-            Durability = 0x00001000,
-            Protection = 0x00002000,
-            Resource = 0x00004000,
-            BaseArmor = 0x00008000,
-            StrBonus = 0x00010000,
-            DexBonus = 0x00020000,
-            IntBonus = 0x00040000,
-            StrReq = 0x00080000,
-            DexReq = 0x00100000,
-            IntReq = 0x00200000,
-            MedAllowance = 0x00400000,
-            SkillBonuses = 0x00800000,
-            PlayerConstructed = 0x01000000
-        }
     }
 }

Projects/UOContent/Items/Clothing/BaseClothing.Migrations.cs

@@ -1,3 +1,5 @@
+using System;
+
 namespace Server.Items;
 
 public partial class BaseClothing
@@ -101,4 +103,23 @@ public partial class BaseClothing
 
         PlayerConstructed = GetSaveFlag(flags, OldSaveFlag.PlayerConstructed);
     }
+
+    private static bool GetSaveFlag(OldSaveFlag flags, OldSaveFlag toGet) => (flags & toGet) != 0;
+
+    [Flags]
+    private enum OldSaveFlag
+    {
+        None = 0x00000000,
+        Resource = 0x00000001,
+        Attributes = 0x00000002,
+        ClothingAttributes = 0x00000004,
+        SkillBonuses = 0x00000008,
+        Resistances = 0x00000010,
+        MaxHitPoints = 0x00000020,
+        HitPoints = 0x00000040,
+        PlayerConstructed = 0x00000080,
+        Crafter = 0x00000100,
+        Quality = 0x00000200,
+        StrReq = 0x00000400
+    }
 }

Projects/UOContent/Items/Clothing/BaseClothing.cs

@@ -880,8 +880,6 @@ namespace Server.Items
             InvalidateProperties();
         }
 
-        private static bool GetSaveFlag(OldSaveFlag flags, OldSaveFlag toGet) => (flags & toGet) != 0;
-
         [AfterDeserialization]
         private void AfterDeserialization()
         {
@@ -902,21 +900,5 @@ namespace Server.Items
             }
         }
 
-        [Flags]
-        private enum OldSaveFlag
-        {
-            None = 0x00000000,
-            Resource = 0x00000001,
-            Attributes = 0x00000002,
-            ClothingAttributes = 0x00000004,
-            SkillBonuses = 0x00000008,
-            Resistances = 0x00000010,
-            MaxHitPoints = 0x00000020,
-            HitPoints = 0x00000040,
-            PlayerConstructed = 0x00000080,
-            Crafter = 0x00000100,
-            Quality = 0x00000200,
-            StrReq = 0x00000400
-        }
     }
 }

Projects/UOContent/Items/Weapons/BaseWeapon.Migrations.cs

@@ -1,3 +1,4 @@
+using System;
 using Server.Engines.Craft;
 
 namespace Server.Items;
@@ -39,4 +40,272 @@ public partial class BaseWeapon
         _aosElementDamages = content.AosElementDamages ?? AosElementAttributesDefaultValue();
         _engravedText = content.EngravedText;
     }
+
+    // Version 9 (pre-codegen)
+    private void Deserialize(IGenericReader reader, int version)
+    {
+        var flags = (OldSaveFlag)reader.ReadInt();
+
+        if (GetSaveFlag(flags, OldSaveFlag.DamageLevel))
+        {
+            _damageLevel = (WeaponDamageLevel)reader.ReadInt();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.AccuracyLevel))
+        {
+            _accuracyLevel = (WeaponAccuracyLevel)reader.ReadInt();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.DurabilityLevel))
+        {
+            _durabilityLevel = (WeaponDurabilityLevel)reader.ReadInt();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Quality))
+        {
+            _quality = (WeaponQuality)reader.ReadInt();
+        }
+        else
+        {
+            _quality = WeaponQuality.Regular;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Hits))
+        {
+            _hitPoints = reader.ReadInt();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.MaxHits))
+        {
+            _maxHitPoints = reader.ReadInt();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Slayer))
+        {
+            _slayer = (SlayerName)reader.ReadInt();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Poison))
+        {
+            _poison = reader.ReadPoison();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.PoisonCharges))
+        {
+            _poisonCharges = reader.ReadInt();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Crafter))
+        {
+            Timer.DelayCall(crafter => _crafter = crafter?.RawName, reader.ReadEntity<Mobile>());
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Identified))
+        {
+            _identified = version >= 6 || reader.ReadBool();
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.StrReq))
+        {
+            _strRequirement = reader.ReadInt();
+        }
+        else
+        {
+            _strRequirement = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.DexReq))
+        {
+            _dexRequirement = reader.ReadInt();
+        }
+        else
+        {
+            _dexRequirement = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.IntReq))
+        {
+            _intRequirement = reader.ReadInt();
+        }
+        else
+        {
+            _intRequirement = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.MinDamage))
+        {
+            _minDamage = reader.ReadInt();
+        }
+        else
+        {
+            _minDamage = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.MaxDamage))
+        {
+            _maxDamage = reader.ReadInt();
+        }
+        else
+        {
+            _maxDamage = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.HitSound))
+        {
+            _hitSound = reader.ReadInt();
+        }
+        else
+        {
+            _hitSound = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.MissSound))
+        {
+            _missSound = reader.ReadInt();
+        }
+        else
+        {
+            _missSound = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Speed))
+        {
+            if (version < 9)
+            {
+                _speed = reader.ReadInt();
+            }
+            else
+            {
+                _speed = reader.ReadFloat();
+            }
+        }
+        else
+        {
+            _speed = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.MaxRange))
+        {
+            _maxRange = reader.ReadInt();
+        }
+        else
+        {
+            _maxRange = -1;
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Skill))
+        {
+            _skill = (SkillName)reader.ReadInt();
+        }
+        else
+        {
+            _skill = (SkillName)(-1);
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Type))
+        {
+            _type = (WeaponType)reader.ReadInt();
+        }
+        else
+        {
+            _type = (WeaponType)(-1);
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Animation))
+        {
+            _animation = (WeaponAnimation)reader.ReadInt();
+        }
+        else
+        {
+            _animation = (WeaponAnimation)(-1);
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Resource))
+        {
+            _resource = (CraftResource)reader.ReadInt();
+        }
+        else
+        {
+            _resource = CraftResource.Iron;
+        }
+
+        Attributes = new AosAttributes(this);
+
+        if (GetSaveFlag(flags, OldSaveFlag.Attributes))
+        {
+            Attributes.Deserialize(reader);
+        }
+
+        WeaponAttributes = new AosWeaponAttributes(this);
+
+        if (GetSaveFlag(flags, OldSaveFlag.WeaponAttributes))
+        {
+            WeaponAttributes.Deserialize(reader);
+        }
+
+        PlayerConstructed = GetSaveFlag(flags, OldSaveFlag.PlayerConstructed);
+
+        SkillBonuses = new AosSkillBonuses(this);
+
+        if (GetSaveFlag(flags, OldSaveFlag.SkillBonuses))
+        {
+            SkillBonuses.Deserialize(reader);
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.Slayer2))
+        {
+            _slayer2 = (SlayerName)reader.ReadInt();
+        }
+
+        AosElementDamages = new AosElementAttributes(this);
+
+        if (GetSaveFlag(flags, OldSaveFlag.ElementalDamages))
+        {
+            AosElementDamages.Deserialize(reader);
+        }
+
+        if (GetSaveFlag(flags, OldSaveFlag.EngravedText))
+        {
+            _engravedText = reader.ReadString();
+        }
+    }
+
+    private static bool GetSaveFlag(OldSaveFlag flags, OldSaveFlag toGet) => (flags & toGet) != 0;
+
+    [Flags]
+    private enum OldSaveFlag
+    {
+        None = 0x00000000,
+        DamageLevel = 0x00000001,
+        AccuracyLevel = 0x00000002,
+        DurabilityLevel = 0x00000004,
+        Quality = 0x00000008,
+        Hits = 0x00000010,
+        MaxHits = 0x00000020,
+        Slayer = 0x00000040,
+        Poison = 0x00000080,
+        PoisonCharges = 0x00000100,
+        Crafter = 0x00000200,
+        Identified = 0x00000400,
+        StrReq = 0x00000800,
+        DexReq = 0x00001000,
+        IntReq = 0x00002000,
+        MinDamage = 0x00004000,
+        MaxDamage = 0x00008000,
+        HitSound = 0x00010000,
+        MissSound = 0x00020000,
+        Speed = 0x00040000,
+        MaxRange = 0x00080000,
+        Skill = 0x00100000,
+        Type = 0x00200000,
+        Animation = 0x00400000,
+        Resource = 0x00800000,
+        Attributes = 0x01000000,
+        WeaponAttributes = 0x02000000,
+        PlayerConstructed = 0x04000000,
+        SkillBonuses = 0x08000000,
+        Slayer2 = 0x10000000,
+        ElementalDamages = 0x20000000,
+        EngravedText = 0x40000000
+    }
 }

Projects/UOContent/Items/Weapons/BaseWeapon.cs

@@ -3571,236 +3571,6 @@ public abstract partial class BaseWeapon
         }
     }
 
-    private static bool GetSaveFlag(OldSaveFlag flags, OldSaveFlag toGet) => (flags & toGet) != 0;
-
-    private void Deserialize(IGenericReader reader, int version)
-    {
-        var flags = (OldSaveFlag)reader.ReadInt();
-
-        if (GetSaveFlag(flags, OldSaveFlag.DamageLevel))
-        {
-            _damageLevel = (WeaponDamageLevel)reader.ReadInt();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.AccuracyLevel))
-        {
-            _accuracyLevel = (WeaponAccuracyLevel)reader.ReadInt();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.DurabilityLevel))
-        {
-            _durabilityLevel = (WeaponDurabilityLevel)reader.ReadInt();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Quality))
-        {
-            _quality = (WeaponQuality)reader.ReadInt();
-        }
-        else
-        {
-            _quality = WeaponQuality.Regular;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Hits))
-        {
-            _hitPoints = reader.ReadInt();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.MaxHits))
-        {
-            _maxHitPoints = reader.ReadInt();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Slayer))
-        {
-            _slayer = (SlayerName)reader.ReadInt();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Poison))
-        {
-            _poison = reader.ReadPoison();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.PoisonCharges))
-        {
-            _poisonCharges = reader.ReadInt();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Crafter))
-        {
-            Timer.DelayCall(crafter => _crafter = crafter?.RawName, reader.ReadEntity<Mobile>());
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Identified))
-        {
-            _identified = version >= 6 || reader.ReadBool();
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.StrReq))
-        {
-            _strRequirement = reader.ReadInt();
-        }
-        else
-        {
-            _strRequirement = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.DexReq))
-        {
-            _dexRequirement = reader.ReadInt();
-        }
-        else
-        {
-            _dexRequirement = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.IntReq))
-        {
-            _intRequirement = reader.ReadInt();
-        }
-        else
-        {
-            _intRequirement = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.MinDamage))
-        {
-            _minDamage = reader.ReadInt();
-        }
-        else
-        {
-            _minDamage = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.MaxDamage))
-        {
-            _maxDamage = reader.ReadInt();
-        }
-        else
-        {
-            _maxDamage = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.HitSound))
-        {
-            _hitSound = reader.ReadInt();
-        }
-        else
-        {
-            _hitSound = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.MissSound))
-        {
-            _missSound = reader.ReadInt();
-        }
-        else
-        {
-            _missSound = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Speed))
-        {
-            if (version < 9)
-            {
-                _speed = reader.ReadInt();
-            }
-            else
-            {
-                _speed = reader.ReadFloat();
-            }
-        }
-        else
-        {
-            _speed = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.MaxRange))
-        {
-            _maxRange = reader.ReadInt();
-        }
-        else
-        {
-            _maxRange = -1;
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Skill))
-        {
-            _skill = (SkillName)reader.ReadInt();
-        }
-        else
-        {
-            _skill = (SkillName)(-1);
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Type))
-        {
-            _type = (WeaponType)reader.ReadInt();
-        }
-        else
-        {
-            _type = (WeaponType)(-1);
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Animation))
-        {
-            _animation = (WeaponAnimation)reader.ReadInt();
-        }
-        else
-        {
-            _animation = (WeaponAnimation)(-1);
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Resource))
-        {
-            _resource = (CraftResource)reader.ReadInt();
-        }
-        else
-        {
-            _resource = CraftResource.Iron;
-        }
-
-        Attributes = new AosAttributes(this);
-
-        if (GetSaveFlag(flags, OldSaveFlag.Attributes))
-        {
-            Attributes.Deserialize(reader);
-        }
-
-        WeaponAttributes = new AosWeaponAttributes(this);
-
-        if (GetSaveFlag(flags, OldSaveFlag.WeaponAttributes))
-        {
-            WeaponAttributes.Deserialize(reader);
-        }
-
-        PlayerConstructed = GetSaveFlag(flags, OldSaveFlag.PlayerConstructed);
-
-        SkillBonuses = new AosSkillBonuses(this);
-
-        if (GetSaveFlag(flags, OldSaveFlag.SkillBonuses))
-        {
-            SkillBonuses.Deserialize(reader);
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.Slayer2))
-        {
-            _slayer2 = (SlayerName)reader.ReadInt();
-        }
-
-        AosElementDamages = new AosElementAttributes(this);
-
-        if (GetSaveFlag(flags, OldSaveFlag.ElementalDamages))
-        {
-            AosElementDamages.Deserialize(reader);
-        }
-
-        if (GetSaveFlag(flags, OldSaveFlag.EngravedText))
-        {
-            _engravedText = reader.ReadString();
-        }
-    }
-
     [AfterDeserialization]
     private void AfterDeserialization()
     {
@@ -3866,42 +3636,6 @@ public abstract partial class BaseWeapon
         }
     }
 
-    [Flags]
-    private enum OldSaveFlag
-    {
-        None = 0x00000000,
-        DamageLevel = 0x00000001,
-        AccuracyLevel = 0x00000002,
-        DurabilityLevel = 0x00000004,
-        Quality = 0x00000008,
-        Hits = 0x00000010,
-        MaxHits = 0x00000020,
-        Slayer = 0x00000040,
-        Poison = 0x00000080,
-        PoisonCharges = 0x00000100,
-        Crafter = 0x00000200,
-        Identified = 0x00000400,
-        StrReq = 0x00000800,
-        DexReq = 0x00001000,
-        IntReq = 0x00002000,
-        MinDamage = 0x00004000,
-        MaxDamage = 0x00008000,
-        HitSound = 0x00010000,
-        MissSound = 0x00020000,
-        Speed = 0x00040000,
-        MaxRange = 0x00080000,
-        Skill = 0x00100000,
-        Type = 0x00200000,
-        Animation = 0x00400000,
-        Resource = 0x00800000,
-        Attributes = 0x01000000,
-        WeaponAttributes = 0x02000000,
-        PlayerConstructed = 0x04000000,
-        SkillBonuses = 0x08000000,
-        Slayer2 = 0x10000000,
-        ElementalDamages = 0x20000000,
-        EngravedText = 0x40000000
-    }
 }
 
 public enum CheckSlayerResult