3 people 724ae71f8a Make NodeId assignment during a node copy explicit (#4157) ...

Fixes #4137.

## The problem

`NodeState.Initialize(ISystemContext, NodeState)` copies a node. Every
child it materialises through `CreateChild` gets a per-instance NodeId
from `ISystemContext.NodeIdFactory`, and is then initialised from its
source on the very next statement - which overwrites that NodeId. The
assignment is therefore *always* discarded: it only burns identifiers,
and permanently leaks them for factories that track outstanding
allocations. Booting the Robotics node manager left ten reservations
behind that every later allocation skipped.

#4123 fixed the symptom by hiding the factory for the duration of the
copy, wrapping the context in one that reports `NodeIdFactory` as
`null`. The review objection was fair: a context that lies about one
property is hard to reason about, and it only works because that
property is allowed to be null.

## What this does

States the intent instead of faking the environment. NodeId assignment
is now an argument of the two members that materialise children:

```csharp
public virtual BaseInstanceState? CreateChild(
    ISystemContext context,
    QualifiedName browseName,
    bool assignInstanceNodeIds = true);

protected virtual BaseInstanceState? FindChild(
    ISystemContext context,
    QualifiedName browseName,
    bool createOrReplace,
    BaseInstanceState? replacement,
    bool assignInstanceNodeIds = true);
```

A copy passes `assignInstanceNodeIds: false` and every node type -
generated or hand-written - sees the real context. There is no
capability property, no wrapper, and no second overload to keep in sync.

`MethodState`, `BaseDataVariableState` and the source generator template
each collapse to a single `FindChild` override that threads the argument
into its `CreateOrReplace<Child>` helpers.

## Breaking change

The four argument `FindChild` and the two argument `CreateChild`
virtuals are gone.

- **Call sites are unaffected.** The new parameter defaults to `true`,
so `CreateChild(context, browseName)` and `FindChild(context,
browseName, true, null)` keep compiling and keep the 1.5.378 behaviour.
- **Overrides must add the parameter.** A node manager that overrides
either member gets `CS0115` until it does. The compiler points at every
site; `docs/migrate/2.0.x/node-states.md` shows the before/after.

This is deliberate, per review: the stack ships all base types, and
types generated from a model are regenerated for 2.0 anyway.

## Also fixed

`MethodState.FindChild` returned `OutputArguments` when asked for
`InputArguments` with `createOrReplace: false` - a pre-existing bug in
the method being restructured. Covered by
`FindChildReturnsTheRequestedArgumentsProperty`.

## Validation

- Full `dotnet build UA.slnx`: **0 errors, 0 warnings**.
- `Opc.Ua.Types.Tests`, `Opc.Ua.SourceGeneration.Core.Tests`,
`Opc.Ua.SourceGeneration.Tests`, `Opc.Ua.Di.Tests`,
`Opc.Ua.Robotics.Tests` - all passing.
- Each new regression test was checked to fail without its corresponding
fix.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Copilot-Session: 8cbb8cd0-f0cb-4ab0-bea2-6202fbf69485
Copilot-Session: f45109d9-59cb-4ffd-a4f7-16e1ea449ae4

2026-08-03 20:36:32 +00:00

..

2.0.x

Make NodeId assignment during a node copy explicit (#4157)

2026-08-03 20:36:32 +00:00