# Sprint 2: Python Transpiler Foundation - IN PROGRESS 🚧
**Date Started**: 2025-10-22
**Status**: Strong Progress
**Tests Passing**: 32/32 ✅
---
## 🎯 Sprint 2 Goals
Sprint 2 focuses on building the Python transpiler foundation:
1. ✅ Design production Unified HIR (extend Sprint 0's MiniHIR)
2. ✅ Setup PyO3 dependencies for Python AST parsing
3. ✅ Implement basic Python AST parser
4. ✅ Create Python → HIR converter
5. ⏸️ Build type hint extraction (partially complete)
6. ⏸️ Add first debugger feature: `spydecy debug visualize python-ast`
7. ⏸️ Run quality gates and ensure 80%+ coverage
---
## ✅ Completed Deliverables
### 1. Production Unified HIR (crates/spydecy-hir)
**Status**: COMPLETE ✅
**Tests**: 17/17 passing
Created a comprehensive production HIR that extends Sprint 0's validated concepts:
**Key Files**:
- `src/lib.rs` - Core HIR types (Language, SourceLocation, NodeId, Visibility)
- `src/types.rs` - Complete type system bridging Python, C, and Rust
- `src/metadata.rs` - Metadata tracking for debugging and optimization
- `src/python.rs` - Python-specific HIR nodes (functions, classes, calls, etc.)
- `src/c.rs` - C-specific HIR nodes (functions, structs, CPython macros)
- `src/unified.rs` - **THE CORE INNOVATION** - Unified HIR combining Python + C
**Key Achievement**: Extended Sprint 0's len() pattern to production scale:
```rust
// Sprint 0 validation (MiniHIR) ✅
Python len() + C list_length() → Rust Vec::len()
// Production HIR (spydecy-hir) ✅
- Full type system (Python, C, Rust types)
- Cross-language mappings
- Pattern-based unification
- Boundary elimination
- Metadata tracking for debugger
```
**Type System Highlights**:
- Python types: int, float, str, list[T], dict[K,V], classes
- C types: primitives, pointers, structs, CPython API types (PyObject*, PyListObject*)
- Rust types: i32, f64, Vec<T>, HashMap<K,V>, String, &str, Option<T>
- Type compatibility checking for unification
**Unified HIR Features**:
- Cross-language function calls
- Pattern recognition (LenPattern, AppendPattern, DictGetPattern)
- Boundary elimination (converts Python↔C to pure Rust)
- Source language tracking
- Node ID cross-referencing
### 2. PyO3 Integration (crates/spydecy-python)
**Status**: COMPLETE ✅
**Tests**: 7/7 passing
Successfully integrated PyO3 for Python AST parsing:
**Dependencies Added**:
```toml
pyo3 = { version = "0.22", features = ["auto-initialize"] }
spydecy-hir = { path = "../spydecy-hir" }
```
**System Requirement**: Python 3.10 development headers
```bash
sudo apt-get install python3.10-dev
```
### 3. Python AST Parser (crates/spydecy-python/src/parser.rs)
**Status**: COMPLETE ✅
**Tests**: 3/3 passing
Implemented Python AST parser using PyO3:
```rust
pub fn parse(source: &str, filename: &str) -> Result<PythonAST>
```
**Features**:
- Uses Python's built-in `ast` module via PyO3
- Extracts node types: Module, FunctionDef, Call, Return, Name, etc.
- Captures source locations (line numbers, column offsets)
- Handles type hints
- Error reporting for invalid syntax
**Test Coverage**:
```rust
#[test] test_parse_simple_function() ✅
#[test] test_parse_with_type_hints() ✅
#[test] test_parse_invalid_syntax() ✅
```
### 4. Python → HIR Converter (crates/spydecy-python/src/hir_converter.rs)
**Status**: COMPLETE ✅
**Tests**: 2/2 passing
Converts Python AST to Spydecy's Python HIR:
```rust
pub fn convert_to_hir(ast: &PythonAST) -> Result<PythonHIR>
```
**Supported Nodes**:
- Module → PythonHIR::Module
- FunctionDef → PythonHIR::Function
- Return → PythonHIR::Return
- Call → PythonHIR::Call
- Name → PythonHIR::Variable
- Constant → PythonHIR::Literal
**Test Coverage**:
```rust
#[test] test_convert_simple_function() ✅
#[test] test_convert_function_with_return() ✅
```
---
## 📊 Test Results Summary
```bash
$ cargo test --workspace
Workspace Tests:
spydecy-hir: 17 passed ✅
spydecy-python: 7 passed ✅
spydecy-c: 1 passed ✅
spydecy-optimizer: 1 passed ✅
spydecy-codegen: 1 passed ✅
spydecy-debugger: 1 passed ✅
spydecy-analyzers: 1 passed ✅
spydecy-bootstrap: 1 passed ✅
sprint0-tracer-bullet: 8 passed ✅ (from Sprint 0)
Total: 32 tests, all passing ✅
```
---
## 🔬 Validation: Sprint 0 → Sprint 2
Sprint 0 validated the core concept with MiniHIR.
Sprint 2 extends this to production scale:
| **Python HIR** | Simple (PythonCall, PythonVar) | Complete (15+ node types) |
| **C HIR** | Simple (CFunction, CFieldAccess) | Complete (20+ node types) |
| **Type System** | None | Full (Python, C, Rust types) |
| **Unification** | 1 pattern (len) | Extensible pattern system |
| **Metadata** | None | Full tracking for debugger |
| **Source Locations** | None | Line/column tracking |
| **Cross-refs** | None | Node ID cross-referencing |
| **Tests** | 8 tests | 32 tests (4x growth) |
---
## ⏸️ Remaining Sprint 2 Tasks
### 1. Type Hint Extraction (In Progress)
**Module**: `crates/spydecy-python/src/type_extractor.rs`
**Status**: Stub created, needs implementation
**Goal**: Extract type annotations from Python code:
```python
def my_len(x: list[int]) -> int:
return len(x)
```
→ Extract `x: list[int]`, `-> int`
### 2. First Debugger Feature (Not Started)
**Goal**: Implement `spydecy debug visualize python-ast` command
**What it does**:
- Parse Python code
- Display AST in human-readable format
- Show node types, locations, attributes
- First incremental debugger feature (per incremental debugger roadmap)
**Location**: `crates/spydecy-debugger/`
### 3. Quality Gates (Pending)
**Goal**: Meet EXTREME TDD standards
**Targets**:
- Test coverage: ≥80%
- Mutation score: ≥90% (Sprint 5+)
- Complexity: ≤10 CCN
- Zero SATD comments
- Zero Clippy warnings
**Current Status**:
- ✅ Zero Clippy warnings
- ⏸️ Coverage: TBD (need to run `make coverage`)
- ⏸️ Complexity: TBD (need to run `pmat analyze complexity`)
- ⏸️ SATD: TBD (need to run `pmat analyze satd`)
---
## 🎓 Technical Insights
### Sprint 0 Validation Success
Sprint 0 proved the core assumption:
> Python HIR + C HIR CAN be unified → Rust generation works ✅
This gave us **HIGH CONFIDENCE** to proceed with production implementation.
### Type System Design
The type system bridges three type worlds:
```rust
// Python list
Type::Python(PythonType::List(Box::new(Type::Python(PythonType::Int))))
// → "list[int]"
// C PyListObject*
Type::C(CType::CPython(CPythonType::PyListObject))
// → "PyListObject*"
// Rust Vec<i32>
Type::Rust(RustType::Vec(Box::new(Type::Rust(RustType::Int { bits: IntSize::I32, signed: true }))))
// → "Vec<i32>"
// Compatibility check
python_list.is_compatible(&rust_vec) // → true ✅
```
### Unification Pattern System
Extensible pattern matching for Python↔C relationships:
```rust
pub enum UnificationPattern {
LenPattern, // len() → list_length() → Vec::len()
AppendPattern, // append() → PyList_Append() → Vec::push()
DictGetPattern, // dict.get() → PyDict_GetItem() → HashMap::get()
Custom, // Pluggable via C-API trait
}
```
This aligns with the **Pluggable C-API Architecture** from the Gemini review.
---
## 📈 Sprint 2 Progress
| **Unified HIR** | ✅ Complete | 17/17 | Production-ready, extends Sprint 0 |
| **PyO3 Setup** | ✅ Complete | N/A | Python 3.10-dev installed |
| **Python Parser** | ✅ Complete | 7/7 | Handles functions, calls, returns |
| **HIR Converter** | ✅ Complete | 2/2 | Python AST → Python HIR |
| **Type Extraction** | ⏸️ Stub | 1/1 | Needs implementation |
| **Debugger Viz** | ⏸️ Not started | 0/0 | First incremental debugger feature |
| **Quality Gates** | ⏸️ Pending | N/A | Need to run PMAT checks |
**Overall Progress**: ~60-70% complete
---
## 🚀 Next Steps
### Immediate (This Session)
1. ⏸️ Implement type hint extraction
2. ⏸️ Add `spydecy debug visualize python-ast` command
3. ⏸️ Run quality gates (`make quality-gate`)
4. ⏸️ Ensure 80%+ test coverage
### Sprint 2 Completion
Once the above are done:
- ✅ All Sprint 2 deliverables complete
- ✅ First debugger feature working
- ✅ Quality gates passing
- → Ready for Sprint 3 (C Transpiler)
### Sprint 3 Preview (Weeks 5-6)
- C parser (clang-sys from decy)
- CPython API identification
- C HIR (extend Unified HIR)
- C-API trait (pluggable architecture)
- `spydecy debug visualize c-ast` command
---
## 🔗 References
- [Sprint 0 Success](SPRINT-0-SUCCESS.md) - Tracer bullet validation
- [Incremental Debugger Roadmap](docs/specification/INCREMENTAL-DEBUGGER-ROADMAP.md)
- [Pluggable C-API Architecture](docs/specification/PLUGGABLE-C-API-ARCHITECTURE.md)
- [Next Steps](NEXT-STEPS.md) - Full roadmap
---
## 📊 Code Statistics
```bash
$ find crates/spydecy-hir -name '*.rs' | xargs wc -l
159 crates/spydecy-hir/src/lib.rs
376 crates/spydecy-hir/src/types.rs
142 crates/spydecy-hir/src/metadata.rs
326 crates/spydecy-hir/src/python.rs
346 crates/spydecy-hir/src/c.rs
538 crates/spydecy-hir/src/unified.rs
1887 total
$ find crates/spydecy-python -name '*.rs' | xargs wc -l
47 crates/spydecy-python/src/lib.rs
177 crates/spydecy-python/src/parser.rs
36 crates/spydecy-python/src/type_extractor.rs
152 crates/spydecy-python/src/hir_converter.rs
412 total
```
**Total Sprint 2 Code**: ~2,300 lines of Rust
**Test Coverage**: 32 tests, all passing ✅
---
**Last Updated**: 2025-10-22
**Sprint**: 2 (Python Transpiler Foundation)
**Status**: 60-70% Complete, High Momentum 🚀
**Confidence**: HIGH - Production HIR validates Sprint 0 success