Feature/306 and fix tests on main

[HowardvanRooijen]

I merged both fixes into a single branch, build the solution and installed the cshap-lsp global tool into the dev container and configured the claude code csharp-lsp. I managed to invoke it and got it to interrogate a project I'm working on:

Server Capabilities (from Initialize Response)

The server reports the following capabilities during LSP handshake:
┌───────────────────────┬───────────┬─────────────────────────────────────────────────┐
│      Capability       │ Supported │                     Details                     │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Text Document Sync    │ ✅        │ Open/close, incremental changes, save with text │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Completion            │ ✅        │ Triggers: ., ' with resolve support             │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Hover                 │ ✅        │ Markdown and plaintext content                  │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Signature Help        │ ✅        │ Triggers: (, ,, <, {, [                         │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Go to Definition      │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Go to Type Definition │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Go to Implementation  │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Find References       │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Document Highlight    │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Document Symbols      │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Code Actions          │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Code Lens             │ ✅        │ With resolve support                            │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Workspace Symbols     │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Document Formatting   │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Range Formatting      │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ On-Type Formatting    │ ✅        │ Triggers: ;, }, )                               │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Rename                │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Call Hierarchy        │ ✅        │                                                 │
├───────────────────────┼───────────┼─────────────────────────────────────────────────┤
│ Semantic Tokens       │ ✅        │ Full token legend                               │
└───────────────────────┴───────────┴─────────────────────────────────────────────────┘
---
Tested Features

1. Hover Information (textDocument/hover)

Request: Position on LoadCommand class name (line 21, character 20)

Response:
```csharp
LoadCommand

Loads a document or directory of documents into the RLM session for processing.
Supports multiple formats: Markdown, PDF, HTML, JSON, Word (.docx), and plain text.

**Capabilities Demonstrated:**
- Returns XML documentation comments
- Markdown formatted output
- Type name with syntax highlighting

---

### 2. Go to Definition (`textDocument/definition`)

**Request:** Position on `CompositeDocumentReader` (line 44, character 12)

**Response:**
```json
{
  "uri": "file://.../Rlm.Cli/Core/Documents/CompositeDocumentReader.cs",
  "range": {
    "start": { "line": 12, "character": 20 },
    "end": { "line": 12, "character": 43 }
  }
}

Capabilities Demonstrated:
- Cross-file navigation
- Precise location (line and character range)
- Resolves to class definition

---
3. Find All References (textDocument/references)

Request: Position on RlmSession (line 80, character 10)

Response: Found 223 references across the codebase

Sample locations:
┌───────────────────┬─────────────────┐
│       File        │      Line       │
├───────────────────┼─────────────────┤
│ RlmSession.cs     │ 12 (definition) │
├───────────────────┼─────────────────┤
│ StoreCommand.cs   │ 30              │
├───────────────────┼─────────────────┤
│ FilterCommand.cs  │ 35              │
├───────────────────┼─────────────────┤
│ LoadCommand.cs    │ 79              │
├───────────────────┼─────────────────┤
│ RlmJsonContext.cs │ 20              │
├───────────────────┼─────────────────┤
│ ...and 218 more   │                 │
└───────────────────┴─────────────────┘
Capabilities Demonstrated:
- Cross-file reference finding
- Includes declaration
- Searches entire solution

---
4. Code Completion (textDocument/completion)

Request: After session. (line 81, character 16)

Response: Incomplete list with members of RlmSession:
┌─────────────────────────┬──────────┬─────────────┐
│          Label          │   Kind   │ Description │
├─────────────────────────┼──────────┼─────────────┤
│ ChunkBuffer             │ Property │             │
├─────────────────────────┼──────────┼─────────────┤
│ Clear                   │ Method   │             │
├─────────────────────────┼──────────┼─────────────┤
│ Content                 │ Property │             │
├─────────────────────────┼──────────┼─────────────┤
│ CurrentChunk            │ Property │             │
├─────────────────────────┼──────────┼─────────────┤
│ CurrentChunkIndex       │ Property │             │
├─────────────────────────┼──────────┼─────────────┤
│ DecrementRecursionDepth │ Method   │             │
├─────────────────────────┼──────────┼─────────────┤
│ Equals                  │ Method   │ (inherited) │
├─────────────────────────┼──────────┼─────────────┤
│ ...more                 │          │             │
└─────────────────────────┴──────────┴─────────────┘
Capabilities Demonstrated:
- Context-aware completions
- Member kind identification (Property=10, Method=2)
- Supports resolve for additional details
- Incremental completion (isIncomplete: true)

---
5. Document Symbols (textDocument/documentSymbol)

Request: Full document structure for LoadCommand.cs

Response: Hierarchical symbol tree:

📄 LoadCommand.cs (File)
└── 📦 Rlm.Cli.Commands (Namespace)
    └── 📦 LoadCommand (Class)
        ├── 📦 Settings (Class)
        │   ├── 🔷 Source (Property) - string
        │   ├── 🔷 Pattern (Property) - string?
        │   └── 🔷 Merge (Property) - bool
        ├── 🔷 ExecuteAsync (Method)
        ├── 🔷 LoadSingleFileAsync (Method)
        ├── 🔷 LoadDirectoryAsync (Method)
        ├── 🔷 MergeDocuments (Method)
        ├── 🔷 DisplayDocumentInfo (Method)
        └── 🔷 CreateCompositeReader (Method)

Capabilities Demonstrated:
- Nested class support
- Property type information in detail field
- Range and selection range for each symbol
- Symbol kinds: File(1), Namespace(3), Class(5), Property(7), Method(6)

---
6. Real-time Diagnostics (textDocument/publishDiagnostics)

Test: Introduced syntax error UNDEFINED_VAR

Response:
{
  "uri": "file://.../LoadCommand.cs",
  "diagnostics": [{
    "range": {
      "start": { "line": 40, "character": 30 },
      "end": { "line": 40, "character": 43 }
    },
    "severity": 1,
    "code": "CS0103",
    "codeDescription": {
      "href": "https://msdn.microsoft.com/query/roslyn.query?appId=roslyn&k=k(CS0103)"
    },
    "source": "lsp",
    "message": "The name 'UNDEFINED_VAR' does not exist in the current context"
  }]
}

Capabilities Demonstrated:
- Real-time error detection on document change
- Precise error location
- C# compiler error codes (CS0103, CS0029, CS0246, etc.)
- Links to documentation
- Severity levels (1 = Error)

---
Additional Tested Error Types
┌────────────┬──────────┬──────────────────────────────┐
│ Error Code │   Type   │           Message            │
├────────────┼──────────┼──────────────────────────────┤
│ CS0103     │ Semantic │ Undefined variable           │
├────────────┼──────────┼──────────────────────────────┤
│ CS0029     │ Type     │ Cannot convert string to int │
├────────────┼──────────┼──────────────────────────────┤
│ CS0246     │ Type     │ Undefined type/class         │
└────────────┴──────────┴──────────────────────────────┘
---
Solution Loading

Capabilities:
- Auto-discovers .sln files in workspace
- Supports explicit --solution flag
- Registers MSBuild SDK (.NET 10.0.101)
- Loads all projects in solution

Log Output:
SDK instances found: .NET Core SDK, Version=10.0.101
MSBuildLocator: will register ".NET Core SDK" as default instance
Using workspaceFolders: file:///workspaces/.../Solutions

---
Performance Notes
┌──────────────────────────┬──────────────────────┐
│        Operation         │       Latency        │
├──────────────────────────┼──────────────────────┤
│ Initialize               │ ~200ms               │
├──────────────────────────┼──────────────────────┤
│ Solution Load            │ ~10-12s (first time) │
├──────────────────────────┼──────────────────────┤
│ Hover                    │ <100ms               │
├──────────────────────────┼──────────────────────┤
│ Definition               │ <100ms               │
├──────────────────────────┼──────────────────────┤
│ References (223 results) │ ~2s                  │
├──────────────────────────┼──────────────────────┤
│ Completion               │ <500ms               │
├──────────────────────────┼──────────────────────┤
│ Diagnostics (on change)  │ ~1-2s                │
└──────────────────────────┴──────────────────────┘
---
Summary

The csharp-ls language server provides comprehensive C# language support including:

✅ Navigation: Definition, type definition, implementation, references
✅ Intelligence: Hover docs, completion, signature help
✅ Analysis: Real-time diagnostics, semantic tokens
✅ Refactoring: Rename, code actions, formatting
✅ Structure: Document symbols, workspace symbols, call hierarchy
✅ Roslyn-powered: Full C# semantic analysis via .NET compiler platform

[Copilot]

Pull request overview

This PR fixes test failures on main and addresses issue razzmatazz#306 by improving error handling in the ProgressReporter and fixing a critical bug in ServerState's diagnostic processing logic. The PR also adds comprehensive unit tests for the ProgressReporter to ensure exceptions from unsupported client methods are handled gracefully.

Changes:

• Added exception handling in ProgressReporter.Begin to gracefully handle clients that don't support window/workDoneProgress/create
• Fixed a bug in ServerState where wf.Value was accessed before null checking, which could cause exceptions
• Improved .cshtml file handling with explicit extension checking and solution loading state management
• Added comprehensive unit tests for ProgressReporter error handling scenarios

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
tests/CSharpLanguageServer.Tests/ProgressReporterTests.fs	New test file validating exception handling in ProgressReporter
tests/CSharpLanguageServer.Tests/CSharpLanguageServer.Tests.fsproj	Added reference to new ProgressReporterTests.fs file
src/CSharpLanguageServer/Lsp/ProgressReporter.fs	Added try-catch to handle exceptions from clients that don't support progress reporting
src/CSharpLanguageServer/State/ServerState.fs	Fixed unsafe Option.Value access, added .cshtml extension check, and improved retry logic for unloaded solutions

---

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