DP44/enriched-qwen3-coder-next/Common/DTS.Common/Events/DTS.Viewer/TestModification.md

---
source_files:
  - Common/DTS.Common/Events/DTS.Viewer/TestModification/RefreshTestRequestEvent.cs
  - Common/DTS.Common/Events/DTS.Viewer/TestModification/ShowT0CursorEvent.cs
  - Common/DTS.Common/Events/DTS.Viewer/TestModification/TestModificationChangedEvent.cs
  - Common/DTS.Common/Events/DTS.Viewer/TestModification/SetUseZeroForUnfilteredEvent.cs
  - Common/DTS.Common/Events/DTS.Viewer/TestModification/TestModificationEvent.cs
  - Common/DTS.Common/Events/DTS.Viewer/TestModification/ShiftT0Event.cs
generated_at: "2026-04-16T03:26:33.870349+00:00"
model: "Qwen/Qwen3-Coder-Next-FP8"
schema_version: 1
sha256: "74b84eb90ba5f23e"
---

# TestModification

## Documentation: Test Modification Event Module

### 1. Purpose  
This module defines a set of Prism-based pub/sub events used to coordinate test modification operations within the DTS Viewer component. It enables decoupled communication between UI components (e.g., viewers, controllers) and backend services (e.g., data processors, ROI generators) when tests are modified, T0 cursor state changes, or related configuration (e.g., `UseZeroForUnfiltered`) is updated. The events serve as a contract for propagating state changes and user actions related to test metadata, cursor positioning, and filtering behavior.

### 2. Public Interface  

- **`RefreshTestRequestEvent`**  
  ```csharp
  public class RefreshTestRequestEvent : PubSubEvent<string> { }
  ```  
  Publishes a request to refresh a specific test, identified by its `string` test ID. Payload is the test ID.

- **`ShowT0CursorEvent`**  
  ```csharp
  public class ShowT0CursorEvent : PubSubEvent<bool> { }
  ```  
  Publishes a request to show or hide the T0 cursor. Payload is a `bool`: `true` to show, `false` to hide.

- **`TestModificationChangedEvent`**  
  ```csharp
  public class TestModificationChangedEvent : PubSubEvent<ITestModificationModel> { }
  ```  
  Publishes when the test modification model has changed. Payload is an `ITestModificationModel` instance representing the new/updated state.

- **`SetUseZeroForUnfilteredEvent`**  
  ```csharp
  public class SetUseZeroForUnfilteredEvent : PubSubEvent<bool> { }
  ```  
  Publishes a request to set the `UseZeroForUnfiltered` property. Payload is a `bool`: `true` means `0` is used in the isocode filter field for unfiltered cases; `false` means `P` is used.

- **`TestModificationEvent`**  
  ```csharp
  public class TestModificationEvent : PubSubEvent<TestModificationArgs> { }
  public class TestModificationArgs
  {
      public string DataSetDirectory { get; }
      public string TestId { get; }
      public TestModificationArgs(string dtsFilePath, string testId)
  }
  ```  
  Publishes whenever a test is modified by the viewer. Payload is a `TestModificationArgs` object containing:
  - `DataSetDirectory`: The path to the data set directory (originally passed as `dtsFilePath`).
  - `TestId`: The ID of the modified test.

- **`ShiftT0Event`**  
  ```csharp
  public class ShiftT0Event : PubSubEvent<ShiftT0EventArguments> { }
  public class ShiftT0EventArguments
  {
      public double T0Time { get; }
      public bool IsInitialization { get; }
      public int T0Steps { get; }
      public bool IsKeyPress { get; }
      public ShiftT0EventArguments(double t0, bool isInitialization)
      public ShiftT0EventArguments(int steps, bool isInitialization, bool isKeyPress)
  }
  ```  
  Publishes a request to shift the T0 time. Payload is a `ShiftT0EventArguments` object, constructed via one of two constructors:
  - `ShiftT0EventArguments(double t0, bool isInitialization)`: For absolute T0 time shifts. Sets `T0Time = t0`, `T0Steps = 0`, `IsKeyPress = false`.
  - `ShiftT0EventArguments(int steps, bool isInitialization, bool isKeyPress)`: For relative shifts (e.g., arrow key navigation). Sets `T0Time = 0`, `T0Steps = steps`, `IsKeyPress = isKeyPress`.

### 3. Invariants  
- All events derive from `Prism.Events.PubSubEvent<T>`, implying they are published/subscribed using Prism’s event aggregation mechanism.
- `TestModificationArgs.TestId` and `TestModificationArgs.DataSetDirectory` are immutable after construction (`private set`).
- `ShiftT0EventArguments` has two mutually exclusive modes of operation:
  - Absolute shift: `T0Time != 0`, `T0Steps == 0`, `IsKeyPress == false`.
  - Relative shift: `T0Time == 0`, `T0Steps != 0`, `IsKeyPress` reflects whether triggered by keyboard.
- `ShowT0CursorEvent` payload is strictly interpreted as a boolean toggle (no undefined or null values).
- `RefreshTestRequestEvent` payload is expected to be a valid test ID string (no validation is performed in this module).

### 4. Dependencies  
- **Dependencies on other modules**:  
  - `Prism.Events` (external library for event aggregation).
  - `DTS.Common.Interface` (for `ITestModificationModel` used in `TestModificationChangedEvent`).
- **Dependencies on this module**:  
  - Inferred consumers include components that handle test modification (e.g., `DataPro` per `TestModificationEvent` summary), UI viewers managing T0 cursor visibility/position, and modules handling isocode filter configuration.  
  - The module is part of `DTS.Common.Events`, suggesting it is consumed by viewer and data processing layers (e.g., `DTS.Viewer`, `DTS.DataPro`).

### 5. Gotchas  
- **Ambiguous naming**: `TestModificationChangedEvent`’s summary says “The Data Folder changed event”, but its payload is `ITestModificationModel`, not a folder path. This appears to be a documentation error.  
- **Constructor overloading ambiguity**: `ShiftT0EventArguments` has two constructors that set different fields; callers must ensure correct constructor is used. Mixing usage (e.g., passing `T0Time` in the steps-based constructor) is prevented by design but may cause confusion if not documented externally.  
- **No validation on payloads**: Events carry raw data (e.g., `string` test IDs, `double` T0 times) without built-in validation—consumers must validate inputs.  
- **`IsKeyPress` in `ShiftT0EventArguments` is only set in the relative-shift constructor**: In the absolute-shift constructor, it is always `false`, which may be non-obvious.  
- **Namespace consistency**: `// ReSharper disable CheckNamespace` is present in some files but not others—suggests possible inconsistency in namespace usage across the codebase (though all events reside in `DTS.Common.Events`).  
- **No versioning or deprecation markers**: Events may evolve without explicit signaling (e.g., adding fields to `TestModificationArgs` could break subscribers).