# Compatibility Analysis: v3.67.0 Sprint Planning

**Generated**: 2025-10-03
**Current Version**: v3.67.0
**Analysis Date**: Post-WASM refactoring release

## Executive Summary

**CRITICAL FINDING**: All three companion repositories are testing against **v3.62.9-v3.63.0** while current release is **v3.67.0** (4-5 versions behind).

### Companion Repository Status

| Repository | Last Tested Version | Current Version | Delta | Status |
|------------|-------------------|-----------------|-------|--------|
| ruchy-book | v3.62.9 | v3.67.0 | 4 versions | ⚠️ **OUTDATED** |
| rosetta-ruchy | v3.63.0 | v3.67.0 | 4 versions | ⚠️ **OUTDATED** |
| ruchy-repl-demos | v3.63.0 | v3.67.0 | 4 versions | ⚠️ **OUTDATED** |

## Repository-Specific Findings

### 1. ruchy-book (77% passing - v3.62.9)

**Overall Status**:
- 92/120 examples passing (77%)
- One-liners: 12/20 passing (60%)
- Last updated: 2025-10-01

**Critical Issues**:

#### P0 - Multi-Variable Expressions Failing
```ruchy
// ❌ FAILING in v3.62.9:
let price = 99.99;
let tax = 0.08;
price * (1.0 + tax)  // Returns only first variable

// Expected: 107.99
// Actual: 99.99
```
**Impact**: Chapter 4 (Practical Patterns) only 50% passing
**Affected**: 5/10 examples in Chapter 4

#### P0 - Dataframes Completely Broken
```ruchy
// ❌ 0/4 examples working (0%)
```
**Impact**: Chapter 18 (Dataframes) completely non-functional
**Affected**: All 4 DataFrame examples

#### P1 - Method Calls Partially Working
```ruchy
// ⚠️ Inconsistent behavior:
(x*x + y*y).sqrt()  // Sometimes works, sometimes fails
```
**Impact**: Mathematical operations unreliable
**Affected**: Chapter 4 one-liners

**Success Areas**:
- ✅ Chapter 1 (Hello World): 14/14 (100%)
- ✅ Chapter 2 (Variables): 8/8 (100%)
- ✅ Chapter 6 (Data Structures): 8/8 (100%)
- ✅ Chapter 10 (I/O): 10/10 (100%)

### 2. rosetta-ruchy (66.7% passing - v3.63.0)

**Overall Status**:
- 70/105 examples passing (66.7%)
- Sprint 36 complete: 4/5 files migrated
- Last updated: 2025-10-01

**Breaking Changes Identified**:

#### BC-1: `from` is Reserved Keyword (CRITICAL)
```ruchy
// ❌ v3.62.12+ - ALL FAIL:
fun test(from: i32) -> i32 { from }  // Parameter
let from = 5;  // Variable
struct Edge { from: i32 }  // Field

// Error: "Function parameters must be simple identifiers..."

// ✅ Solution: Rename to from_vertex, source, etc.
```
**Impact**: 🔴 CRITICAL - affects ANY identifier named `from`
**Files Affected**: dijkstra, tsp, graph_analytics
**Status**: ✅ RESOLVED in migrated files

#### BC-2: Parser Bug - Array References with 3+ Parameters
```ruchy
// ✅ Works:
fun test(arr: &[i32; 25]) -> i32 { 42 }  // 1 param
fun test(arr: &[i32; 25], x: i32) -> i32 { 42 }  // 2 params

// ❌ FAILS:
fun test(arr: &[i32; 25], x: i32, y: i32) -> i32 { 42 }  // 3 params
```
**Impact**: 🔴 CRITICAL - blocks reference-based migration
**Workaround**: Use wrapper structs
**Status**: ✅ Pattern validated

#### BC-3: No `mut` in Tuple Destructuring
```ruchy
// ❌ FAILS:
let (mut x, mut y) = ...

// ✅ WORKS:
let (x, y) = ...;
let mut x = x;
```
**Impact**: 🟡 MEDIUM - affects functional patterns
**Files Affected**: stream_processing, topological_sort

**Success Areas**:
- ✅ data-science: 26/32 (81.2%)
- ✅ algorithms: 44/72 (61.1%)

### 3. ruchy-repl-demos (100% pass - v3.63.0)

**Overall Status**:
- 100% test pass rate (3/3 tests)
- 180 total demos
- Last updated: 2025-10-01

**Issues**:

#### Coverage Gap
- Only 46% estimated coverage
- Need more test files
- 7 test files for 180 demos

**Strengths**:
- ✅ All quality gates passing
- ✅ Toyota Way compliant
- ✅ Zero SATD comments

## Version History Analysis

### Changes v3.63.0 → v3.67.0

**v3.64.0-v3.66.0** (Unknown - need to check CHANGELOG.md):
- 3 versions between last tests and pre-WASM refactoring
- May contain parser fixes or regressions

**v3.67.0** (Current - WASM refactoring):
- 24 helper functions extracted
- WASM backend complexity reduced 80-90%
- All functions <10 complexity
- Should NOT affect interpreter/transpiler

**Risk Assessment**:
- 🟢 **LOW**: WASM refactoring isolated to backend
- 🟡 **MEDIUM**: Parser/interpreter changes in v3.64-v3.66 unknown
- 🔴 **HIGH**: 4-5 version gap = potential regressions undetected

## Priority Action Plan

### Phase 1: Baseline Testing (MANDATORY)
**Goal**: Establish v3.67.0 compatibility baseline for all three repos

```bash
# 1. ruchy-book
cd ../ruchy-book
make test-comprehensive  # Re-run all 120 examples
make sync-version  # Update to v3.67.0

# 2. rosetta-ruchy
cd ../rosetta-ruchy
make test-all-examples  # Re-run all 105 examples

# 3. ruchy-repl-demos
cd ../ruchy-repl-demos
make test  # Re-run all tests
```

**Expected Outcomes**:
- Identify any regressions from v3.63.0 → v3.67.0
- Update integration reports with v3.67.0 results
- Confirm WASM refactoring didn't break interpreter

### Phase 2: Critical Bug Fixes (P0)
**Based on current known issues**:

1. **Multi-variable expressions** (ruchy-book)
   - Investigate why only first variable returned
   - Likely interpreter bug in expression evaluation
   - Add regression test before fixing

2. **DataFrame support** (ruchy-book)
   - Currently 0/4 working (0%)
   - May need feature implementation
   - Check if dataframe feature flag enabled

3. **Parser bugs** (rosetta-ruchy)
   - Array reference parameter parsing
   - Tuple destructuring with mut
   - File upstream bugs if confirmed

### Phase 3: Coverage Improvement (P1)

1. **ruchy-book**:
   - Target: >85% success rate (from 77%)
   - Focus: Chapters 17 (Error Handling) and 18 (Dataframes)

2. **rosetta-ruchy**:
   - Target: >75% success rate (from 66.7%)
   - Complete Sprint 36: Finish remaining 1/5 file

3. **ruchy-repl-demos**:
   - Target: >80% test coverage (from 46%)
   - Add test files for uncovered categories

## Testing Protocol

### MANDATORY Commands (Per CLAUDE.md)

```bash
# Before ANY fixes:
pmat tdg . --min-grade A- --fail-on-violation
cargo test --all
make coverage

# After each fix:
cargo test <specific_test>
pmat tdg <modified_file.rs> --include-components

# Before commit:
pmat tdg . --min-grade A- --fail-on-violation
make lint
make coverage
```

### Toyota Way Compliance

**Jidoka (Quality Built-In)**:
- All fixes must include regression tests
- No fix without proof via TDD

**Genchi Genbutsu (Go and See)**:
- Run actual compatibility tests
- Don't assume based on version numbers

**Kaizen (Continuous Improvement)**:
- Update integration reports after each test run
- Track improvements sprint-over-sprint

**Hansei (Reflection)**:
- Document root causes of failures
- Prevent similar issues in future versions

## Success Metrics

### Sprint Goals

**Immediate (Sprint 3)**:
- ✅ Baseline v3.67.0 compatibility established for all 3 repos
- ✅ Integration reports updated
- ✅ Critical regressions identified and documented

**Short-term (Sprint 4-5)**:
- 🎯 ruchy-book: >85% pass rate
- 🎯 rosetta-ruchy: >75% pass rate
- 🎯 ruchy-repl-demos: >80% test coverage

**Medium-term (Sprint 6-10)**:
- 🎯 ruchy-book: >90% pass rate
- 🎯 rosetta-ruchy: 100% Sprint 36 migration complete
- 🎯 ruchy-repl-demos: 100% test coverage

## Next Immediate Actions

1. **Re-run ruchy-book tests** with v3.67.0
2. **Re-run rosetta-ruchy tests** with v3.67.0
3. **Re-run ruchy-repl-demos tests** with v3.67.0
4. **Generate comparison report**: v3.63.0 vs v3.67.0 results
5. **Prioritize fixes** based on regression analysis

---

**Status**: 🚧 Analysis complete, testing phase starting
**Next Update**: After Phase 1 baseline testing complete
