# Sprint 71 - Session 2 Handoff

**Date:** October 30, 2025
**Session:** TRACE-003 Completion (80% → 100%)
**Sprint:** 71 - Debug Adapter Protocol (DAP) Implementation

## Session Overview

Successfully completed TRACE-003 (Variable Inspection with AST) by fixing all 3 remaining test failures. All 15 tests now passing with zero ignored tests. Sprint 71 is now 75% complete.

## Commits Made

### TRACE-003 Completion (c72b5d0e)
- **Status:** ✅ 100% Complete
- **Tests:** 15/15 passing (was 12/15 at session start)
- **Files Modified:**
  - `server/src/services/dap/variable_inspector.rs` (+40 lines)
  - `server/tests/variable_inspector_tests.rs` (-12 #[ignore] attributes)

## Fixes Implemented

### Fix #1: Line Bounds Validation
- **Problem:** `test_invalid_line_number` accepted invalid line numbers silently
- **Solution:** Added validation in `extract_variables_rust/typescript/python`
- **Location:** server/src/services/dap/variable_inspector.rs:93-96, 129-133, 164-168
- **Result:** Returns descriptive error: "Line X is out of bounds (file has Y lines)"

### Fix #2: Arrow Function Support
- **Problem:** `test_typescript_arrow_function_parameters` failed to extract parameters
- **Root Cause:** Arrow functions in TypeScript use `formal_parameters` children, not field access
- **Solution:**
  - Enhanced `find_parent_function` to traverse into `arrow_function` nodes within `lexical_declaration` (lines 228-241)
  - Updated `extract_ts_function_params` to find `formal_parameters` children (lines 386-400)
- **Result:** Both regular functions and arrow functions now supported

### Fix #3: Variable Shadowing/Deduplication
- **Problem:** `test_variable_shadowing` returned wrong type (i32 instead of &str)
- **Root Cause:** Collecting all variables without deduplication
- **Solution:** Implemented `deduplicate_variables` helper method (lines 493-506)
- **Result:** Correctly handles Rust shadowing: `let x = 10; let x = "hello"` → returns "&str"

## Test Results

```bash
$ cargo test --test variable_inspector_tests

running 15 tests
test test_auto_language_detection ... ok
test test_empty_scope ... ok
test test_inspect_from_file ... ok
test test_invalid_line_number ... ok
test test_multiple_assignments ... ok
test test_performance_large_scope ... ok
test test_python_function_parameters ... ok
test test_python_simple_variables ... ok
test test_rust_function_parameters ... ok
test test_rust_nested_scopes ... ok
test test_rust_simple_local_variables ... ok
test test_syntax_error_handling ... ok
test test_typescript_arrow_function_parameters ... ok
test test_typescript_simple_variables ... ok
test test_variable_shadowing ... ok

test result: ok. 15 passed; 0 failed; 0 ignored
Time: <0.01s
```

## Sprint 71 Progress

**Overall:** 75% complete (3/4 tickets)

- ✅ **TRACE-001:** DAP Protocol Server - 100% (10/10 tests)
- ✅ **TRACE-002:** Breakpoint Management System - 100% (15/15 tests)
- ✅ **TRACE-003:** Variable Inspection with AST - 100% (15/15 tests) ← **COMPLETED THIS SESSION**
- ⏸️ **TRACE-004:** DAP-PMAT Integration - Not started (estimated 4-6 hours)

## TRACE-004: Next Steps

**Goal:** Integrate DAP components with PMAT's existing analysis infrastructure

### Required Integration Points

1. **Language Detection** (from spec lines 499-517)
   - Use PMAT's `LanguageAnalyzer` to detect file language
   - Support Rust, TypeScript, Python
   - Return `Language` enum from DapServer

2. **Tree-Sitter AST Integration** (from spec lines 519-540)
   - Parse files using PMAT's tree-sitter parsers
   - Store AST for breakpoint validation
   - Method: `has_ast_for(path: &str) -> bool`

3. **Variable Inspection Integration** (from spec lines 542-570)
   - Use `VariableInspector` to extract variables at breakpoints
   - Integrate with DAP `scopes` and `variables` requests
   - Leverage PMAT's deep context system

4. **Test Fixtures** (from spec lines 709-711)
   - Create `tests/fixtures/sample.rs` - Simple Rust file
   - Create `tests/fixtures/sample.py` - Simple Python file
   - Create `tests/fixtures/complex.rs` - Complex test case with nested scopes

### Recommended Implementation Order

#### Phase 1: Test Fixtures (30 min)
```bash
mkdir -p server/tests/fixtures
```

Create simple test files:
- `sample.rs`: ~10 lines, basic function with variables
- `sample.py`: ~10 lines, basic function with variables
- `complex.rs`: ~30 lines, nested scopes, multiple functions

#### Phase 2: RED Phase - Integration Tests (1-2 hours)
Create `server/tests/dap_integration_tests.rs`:

```rust
// Test 1: Language detection
#[test]
fn test_dap_detects_rust_language() {
    let mut server = DapServer::new();
    server.launch("tests/fixtures/sample.rs");
    assert_eq!(server.current_language(), Some(Language::Rust));
}

// Test 2: Tree-sitter AST storage
#[test]
fn test_dap_stores_ast_for_breakpoints() {
    let mut server = DapServer::new();
    server.launch("tests/fixtures/sample.py");
    server.set_breakpoint("tests/fixtures/sample.py", 5);
    assert!(server.has_ast_for("tests/fixtures/sample.py"));
}

// Test 3: Variable inspection integration
#[test]
fn test_dap_extracts_variables_at_breakpoint() {
    let mut server = DapServer::new();
    server.launch("tests/fixtures/complex.rs");
    server.stop_at_line(10);

    let vars = server.get_variables_at_current_line();
    assert!(vars.len() > 0);
}

// Tests 4-10: Additional integration scenarios
```

#### Phase 3: GREEN Phase - Implementation (2-3 hours)

Extend `server/src/services/dap/server.rs`:

```rust
impl DapServer {
    // Add language detection field
    current_language: Option<Language>,
    current_file: Option<PathBuf>,
    ast_cache: HashMap<PathBuf, Tree>,

    // New methods
    pub fn current_language(&self) -> Option<Language> { ... }
    pub fn has_ast_for(&self, path: &str) -> bool { ... }
    fn detect_language(&mut self, path: &Path) { ... }
    fn parse_and_cache_ast(&mut self, path: &Path) { ... }
}
```

#### Phase 4: REFACTOR + Commit (30 min)
- Clean up code
- Remove duplication
- Ensure all tests passing
- Commit with comprehensive message

### Estimated Time Breakdown

| Phase | Task | Time |
|-------|------|------|
| 1 | Test fixtures | 30 min |
| 2 | RED phase tests | 1-2 hours |
| 3 | GREEN implementation | 2-3 hours |
| 4 | REFACTOR + commit | 30 min |
| **Total** | **TRACE-004** | **4-6 hours** |

## Repository State

- **Branch:** master
- **Version:** v2.181.0
- **Latest Commit:** c72b5d0e (TRACE-003 completion)
- **Uncommitted Files:** None
- **Quality Gates:** All passing ✅

## Testing Commands

```bash
# Run all DAP tests
cargo test --test dap_server_tests           # 10/10 passing
cargo test --test breakpoint_manager_tests   # 15/15 passing
cargo test --test variable_inspector_tests   # 15/15 passing

# When TRACE-004 is ready
cargo test --test dap_integration_tests      # Target: 10+ tests
```

## Files Structure

```
server/
├── src/services/dap/
│   ├── mod.rs                    # Module exports
│   ├── types.rs                  # DAP protocol types (TRACE-001)
│   ├── server.rs                 # DapServer (TRACE-001)
│   ├── breakpoint_manager.rs     # Breakpoints (TRACE-002)
│   └── variable_inspector.rs     # Variables (TRACE-003) ✅ Complete
│
├── tests/
│   ├── dap_server_tests.rs       # TRACE-001 tests ✅
│   ├── breakpoint_manager_tests.rs # TRACE-002 tests ✅
│   ├── variable_inspector_tests.rs # TRACE-003 tests ✅
│   └── dap_integration_tests.rs  # TRACE-004 tests ⏳ Next
│
└── tests/fixtures/                # ⏳ To create
    ├── sample.rs
    ├── sample.py
    └── complex.rs
```

## Next Session Recommendations

### Option 1: Complete TRACE-004 (Recommended)
- Finish Sprint 71 at 100%
- Full DAP-PMAT integration
- Estimated: 4-6 hours
- High impact: Completes entire sprint

### Option 2: Begin Sprint 72
- Move to next sprint in roadmap
- TRACE-004 can be completed later
- Current DAP implementation is functional

### Option 3: Other Work
- User may request different tasks

## Session Metrics

- **Duration:** ~2 hours (TRACE-003 completion)
- **Tests Fixed:** 3/3 (100% success rate)
- **Tests Passing:** 15/15 (100%)
- **Code Quality:** Zero warnings, all quality gates passing
- **Sprint Progress:** 50% → 75% (+25%)

---

**Handoff Complete**
Session ready for TRACE-004 implementation or alternative direction.

**Key Insight:** TRACE-003 required careful AST investigation using debug tests to understand actual tree-sitter node structures. This debug-driven development approach was critical to success. TRACE-004 will benefit from this same methodology when integrating with PMAT's existing parsers.
