## Summary
Consolidates the duplicated inline AOS attribute → `ObjectPropertyList` emission that each item base copy-pastes into per-family `GetProperties(IPropertyList)` methods, mirroring the existing `AosSkillBonuses.GetProperties` precedent.
### Per-family `GetProperties(IPropertyList)`
- **`AosAttributes`** — the 24 common attributes in canonical cliloc-ascending order, with optional `damageBonus` / `hitChanceBonus` / `luckBonus` params so item-computed bonuses (e.g. `GetDamageBonus()`) stay out of the family type.
- **`AosWeaponAttributes`** — `UseBestSkill`, the `Hit*` block (1060416–1060430), `MageWeapon` (`30 - prop`), `SelfRepair`.
- **`AosArmorAttributes`** — `MageArmor`, `SelfRepair` (the always-direct members; `LowerStatReq`/`DurabilityBonus` stay inline since they're item-computed in armor but container-direct in clothing).
### Rewired all 6 `AosAttributes`-emitting item bases
`BaseJewel`, `BaseArmor`, `BaseClothing`, `BaseWeapon`, `BaseTalisman`, `Spellbook` now call the family methods instead of inlining the chain. Net: large dedup in `BaseWeapon`/`BaseArmor`/`BaseClothing`/`BaseTalisman`/`Spellbook`.
## Behavior change: tooltip line **order** (set preserved)
This is **not** a pure no-op refactor, and that's unavoidable. Today the families are emitted **interleaved in cliloc order**, and the relative order differs per item class — e.g. `BonusDex` (1060409) is emitted early in `BaseArmor` but **after** the `Hit*` block in `BaseWeapon`. No single emission order reproduces every class byte-for-byte, so consolidating into contiguous per-family blocks necessarily **de-interleaves**: lines regroup **specific → general** (family-specific, then common `AosAttributes`).
- The **set** of emitted `(cliloc, argument)` lines per item is preserved **exactly** — nothing dropped, added, or value-changed.
- Only the **order** of lines within a tooltip changes for `BaseArmor` / `BaseWeapon` / `BaseClothing`. `BaseJewel` / `BaseTalisman` / `Spellbook` were already canonical, so those are byte-identical.
## Tests
- **Golden set-invariance tests** per item base (`BaseArmor/Clothing/Jewel/Weapon/Talisman/Spellbook PropertiesTests`) — each was written to pass against current `main` **before** the rewire (locking the emitted-line set), then confirmed still passing after, proving no line is lost/added/changed.
- Family-level unit tests for each `GetProperties` (canonical order, computed-bonus folding, the `AosArmorAttributes` exclusions).
- `dotnet build` clean; full `UOContent.Tests` green. (Pre-existing `AccountPacket`/`GumpPacket`/`MobilePacket`/`ClientEnumerator` golden-test failures reproduce on unmodified `main` and are unrelated to this change.)
## Summary
- **Add a self-referencing `InterpolationHandler` to `ValueStringBuilder`** that writes directly into the builder's buffer — zero intermediate allocation, works with `stackalloc`-backed builders
- **Replace all `System.Text.StringBuilder` usage** across the codebase with `ValueStringBuilder`
- **Convert `ValueStringBuilder.Create()` to `stackalloc`** at 10 sites where output length is provably bounded
- **Convert manual `Dispose()` to `using var`** where possible, and hoist loop-scoped builders outside loops with `Reset()`
- **Convert verbose `Append()` chains to `Append($"...")`** interpolation for readability
- **Add comprehensive documentation** for string handling patterns
## InterpolationHandler Design
`ValueStringBuilder` is a `ref struct`, which creates challenges for C#'s interpolated string handler pattern:
- **`ref` fields to ref structs are not allowed** (CS9050)
- **`[InterpolatedStringHandlerArgument("")]` passes struct receivers by value**, not by ref
- **`ISelfInterpolatedStringHandler` requires boxing** ref structs into interface fields
**Solution: Copy-and-reconcile pattern.** The handler receives a value copy of the builder. The copy shares the same underlying `char` buffer (`Span` points to the same `stackalloc`/pooled memory), so writes go to the original buffer. `Append()` reconciles by `this = handler._builder`, updating `_length` and any buffer references changed by `Grow()`.
This is safe because:
- The game loop is single-threaded — no concurrent access between handler construction and reconciliation
- If `Grow()` occurs in the copy, the original's stale buffer isn't accessed until `Append()` replaces it
- `Dispose()` correctly returns the reconciled buffer to the pool
## Changes by Category
### ValueStringBuilder (`Projects/Server/Buffers/ValueStringBuilder.cs`)
- Added nested `InterpolationHandler` ref struct with copy-and-reconcile pattern
- Added `Append([InterpolatedStringHandlerArgument("")] scoped ref InterpolationHandler)` method
- Removed `RawInterpolatedStringHandler` overloads (new handler replaces them)
- All `AppendFormatted` overloads delegate to existing `Append` methods (no code duplication)
- Alignment support via direct private field access (nested type privilege)
### StringBuilder → ValueStringBuilder (15 files)
Replaced all `new StringBuilder()` with `ValueStringBuilder.Create()` or `stackalloc`:
- ConPVP games: KingOfTheHill, DoubleDom, CTF, BombingRun, TourneyMatch
- ConPVP infrastructure: Tournament, Participant, TourneyParticipant
- ConPVP gumps: ArenaGump, TournamentBracketGump, AcceptTeamGump, ConfirmSignupGump
- Commands: Handlers, Logging, Add
- Other: TownCrier, SpeechLogGump, TestCenter
Key patterns:
- `sb = new StringBuilder()` reassignment → `sb.Reset()`
- `sb.AppendFormat("{0:N0}", value)` → `sb.Append($"{value:N0}")`
- `sb.Append(x).Append(y)` chains → separate statements (VSB returns void)
### Create() → stackalloc (10 files)
Converted heap-allocated builders to stackalloc where output is bounded:
- ClientVersion (32), MapSelection (160), HouseRaffleStone (48)
- HolySense (96), UnholySense (96), ClientVerification (192)
- AcceptTeamGump (64), ConfirmSignupGump (64)
- BaseWeapon (160), BaseArmor (128)
### Loop optimizations (2 files)
Hoisted `ValueStringBuilder` creation outside loops with `Reset()` per iteration:
- TourneyMatch.cs: `using var` inside for loop → stackalloc before loop
- ArenaGump.cs: `Create()` + `Dispose()` per iteration → stackalloc before loop
### Append chain → interpolation (5 files)
Converted multi-line `Append()` chains to `Append($"...")`:
- BountyMessage.cs: title switch (6 cases), paragraph (15→1 Append), description lines, closing
- AcceptTeamGump, ConfirmSignupGump, TournamentBracketGump: tournament type strings
- AdminGump: comment/tag formatting in loops
### Documentation
- `dev-docs/string-handling.md`: Full reference — construction, interpolation, disposal, decision guide
- `dev-docs/claude-skills/modernuo-string-handling.md`: Claude skill with quick reference
- `CLAUDE.md`: Added rule 17 (no StringBuilder), dev-docs table entry, skills table entry
- `dev-docs/code-standards.md`: Updated memory management section
## Test Plan
- [x] `dotnet build` — 0 errors, 0 warnings
- [x] `dotnet test` — 940/940 tests pass
- [x] 28 ValueStringBuilder tests covering all reconciliation scenarios:
- Stackalloc no-grow, stackalloc with grow (→pool transition)
- Heap no-grow, heap with grow, heap double grow
- Pre-existing content with and without grow
- Sequential multiple `Append($"...")` calls
- Mixed plain + interpolated Append
- Empty interpolation, literal-only, format specifiers
- Null string holes, ISpanFormattable types
- Dispose after stackalloc→pool grow
## Summary
### Changes
- Adds `[IgnoreDupe]` and `[SerializedIgnoreDupe]`
- Updates all _known_ classes that need the attribute. Some might be missing, please helps us find them!
- Adds `Item.Dupe()` command and encapsulates `CopyProperties` and `OnAfterDuped`. This is also overridable.
- Updates Dupe command to use the new logic.
- Fixes duping multiple kinds of objects that used to be outright broken.
### Bug Fixes
- Fixes issue with durability after duping
- Fixes issue with hue after duping
> [!Note]
> **Developer Note**
> Customizing how duping an item works now requires two steps:
> 1. Add `[IgnoreDupe]` or `[SerializedIgnoreDupe]` to the property/field
> 2. Add custom logic in an `OnAfterDuped` override
>
> When do you need to do this?
> *When the property being copied is not a primitive, and you need to manually deep-clone the contents of the property such as with Lists, Dictionaries, or sub classes.*
* Adds `SerializationProperty` - This will generate the private variable for serialization. Also provides an option `useField` to specify your own. Example:
```cs
[SerializationProperty(0, useField: nameof(_resource)]
```
## Changes
- [X] Adds OPL convenience methods
- `opl.Add(cliloc, value)` and `opl.Add(value)` - value as an integer or string works just like `opl.Add(cliloc, $"{value}")`
- `opl.AddLocalized(cliloc, clilocValue)` - works the same as `opl.Add(cliloc, $"#{clilocValue}");`
- [X] Simplifies basic `list.Add()` situations
- [X] Changes cliloc as an argument so it works with custom IPropertyList implementations (HTML)
- [X] Fixes plants so they support the old localization and new (changed in 7.0.12.0+)
- [X] Exposes more methods to override for Item to make creating custom OPL possible.
## Important Notes
* Using a ternary as an argument, like this `opl.Add(number, showType ? $"{type}\t{value}" : $"{value}");` _will not use the correct string interpolation_. This means if you use a custom PropertyList (for HTML or some other purpose), the property list won't be localized properly.
* All localization values must be interpolated, even if they are literal strings, or integers. Example: `opl.Add(number, $"{"Charges"}\t{m_Charges}");` is correct. Using the following: `$"Charges\t{m_Charges}"` will not work for custom PropertyList implementations!
## Breaking Changes (New API)
ObjectPropertyList supports the following API:
```cs
list.Add(500000);
list.Add(500001, stringArgument);
list.Add("Some text");
list.Add($"Some text with {argument}");
list.Add(500002, $"{arg1}\t{arg2}");
```
## Notes
1. All API uses that require a formatter like this:
```cs
list.Add(500002, "{0}\t{1}", arg1, arg2);
```
Should be changed to use string interpolation, for example:
```cs
list.Add(500002, $"{arg1}\t{arg2}");
```
2. The following paradigm should no longer be used:
```cs
list.Add(1061170, prop.ToString()); // strength requirement ~1_val~
```
The new string interpolation API will avoid having to convert the argument to a string before writing it to the packet. Instead use the following:
```cs
list.Add(1061170, $"{prop}"); // strength requirement ~1_val~
```
### Benchmarks
```cs
| Method | Mean | Error | StdDev | Gen 0 | Allocated |
|------------------------------- |---------:|--------:|--------:|-------:|----------:|
| BenchmarkOldOPL | 241.0 ns | 0.56 ns | 0.47 ns | 0.0105 | 88 B |
| BenchmarkStringInterpolatedOPL | 199.9 ns | 2.44 ns | 2.39 ns | - | - |
```
### Changes
- [X] Removes crash in STArray.Return when array is null.
- [X] Fixes NPE in OPL when entity is null. Serial in packet will be 0 when entity is null.
- [X] Fixes NPE in AosAttributes when Parent is null.
- [X] Changes OPL to use string interpolation.
- [X] Introduces `IPropertyList` to allow extending PropertyList for other uses.
* Adds `RaceFlag` to the `Race` object. This is `1 << RaceIndex`
* Replaces `RequiredRace` with `RequiredRaces` for items.
* Adds convenience flags for `RequiredRaces`
```cs
public const int AllowAllRaces = 0x7; // Race.Human.RaceFlag | Race.Elf.RaceFlag | Race.Gargoyle.RaceFlag
public const int AllowHumanOrElves = 0x3; // Race.Human.RaceFlag | Race.Elf.RaceFlag
public const int AllowElvesOnly = 0x2; // Race.Elf.RaceFlag
public const int AllowGargoylesOnly = 0x4; // Race.Gargoyle.RaceFlag
```
* Example usage on an item:
```cs
public override int RequiredRaces => Race.AllowHumanOrElves;
```
* Adds Wood and Stone armor material types
* Updates Woodland armor to Wood
* Adds proper messaging for race restrictions
* Adds gargoyle only for object properties
* Adds `CheckRace` functions for validating if a race or mobile can use the item:
```cs
bool CheckRace(Race race);
bool CheckRace(Mobile from, bool message = true);
```
* Adds save flag support (see `ElvenGlasses` for an example)
* Updates AOSAttributes so they are code genned
* Fixes embedded object support by adding an `IRawSerializable`
* Fixes various inconsistencies in serializing with codegen
- [X] Adds a property to `CommandProperty` to allow modifying `PropertyObject` where there is no property setter that is accessible.
- [X] Updates AosAttributes and friends
Example of how to make this work:
```cs
[CommandProperty(AccessLevel.GameMaster, canModify: true)]
public AosWeaponAttributes WeaponAttributes { get; private set; }
```
This fix is necessary because in release mode the optimizer will sometimes _entirely remove the setter_ because it knows it can do something that is more efficient _when the property setter is private_. RunUO got around this by declaring a public setter explicitly that _was empty_.
### Screenshot
<img width="313" alt="Screen Shot 2021-05-15 at 11 34 01 PM" src="https://user-images.githubusercontent.com/3953314/118387955-49293c00-b5d6-11eb-8f31-a3b5e31bd18b.png">
- [X] Fixes an issue where a buffer smaller than 8 bytes would not double with enough space in some cases.
- [X] Fixes an issue with dupe copying the savebuffer reference (ugh).
- [X] Streamlines the IGenericWriter API to use better generics.
- [X] Streamlines the IGenericReader API to use better generics.
- [X] Forces `tidying` of a List/HashSet to be done externally since Writers/Readers should not have side effects.
- [X] Fixes an issue where Tidying a list didn't TrimExcess, causing memory leaks.
- [X] Reverted the meaning of `World.Running` to specifically refer to any world state post world loading.
- NOTE: Do not use this if you want to block on world saves. Instead use checks against `WorldState.Saving` states.
- [X] Fixes an issue with serializing negative DateTime deltas.
- [X] Fixes a potential issue with serializing non-UTC DateTime.
Bumps release version
### API Breaking Change
Combined `AsciiMessage` and `UnicodeMessage` into a single function that takes two arguments, `bool ascii` and `string lang`. Lang can be null (or anything) if ascii is true.
- [X] Changes message packets
- [X] Cleans up some code
- [X] Uses benchmarks to determine if the spanwriter + copyfrom
### Change to how DisplayEquipInfo works
* Fixes a bug where raw name wasn't used
* Fixes another bug where an empty, blank, or null string was still sending an empty crafted by property.
Bumps release version
- [X] Fixes several bugs
- [X] Updates more ordinal issues
- [X] Cleans up the code a bit
- [X] Turns classes static that should have been
- [X] Changes TcpServer.Instances to a HashSet
Bumps release version
