v0.3.1

SQLAlchemy Support

This release adds SQLAlchemy 0.3.1 support with savepoint-based transaction isolation.

Session Management

• Hook into Session.commit() to prevent actual commits
• Wrap sessions in nested transactions (savepoints)
• Handle Session.rollback() within tests
• Support scoped session patterns
• Handle session-per-request patterns

Engine Configuration

• Detect SQLAlchemy engine configuration
• Apply connection pooling optimizations
• Handle multiple engines (read replicas, etc.)
• Support async SQLAlchemy (asyncpg, aiosqlite)
• Handle engine disposal (dispose pattern after fork)

Alembic Integration

• Detect Alembic migration configuration
• Verify migration state matches expected

New Functions

• _apply_sqlalchemy_isolation(engine, session_factory)
• _cleanup_sqlalchemy_isolation(isolation_context)
• _apply_sqlalchemy_isolation_async(engine, session_factory)
• _cleanup_sqlalchemy_isolation_async(isolation_context)
• _apply_sqlalchemy_isolation_scoped(engine, scoped_session)
• _apply_sqlalchemy_isolation_multi(engines)
• _detect_sqlalchemy()
• _detect_alembic()
• _verify_alembic_head(alembic_cfg)

Rust Integration

• Added SqlAlchemyDbSetup HookEffect variant

v0.3.0

🎉 Django Database Integration

This release adds comprehensive Django database support for Tach, enabling proper test isolation for database-heavy test suites.

New Features

CLI Flags (#37)

• --reuse-db - Reuse existing test database between runs (speeds up repeated test runs)
• --create-db - Force recreation of test database (use after schema changes)

Transaction Support (#40)

• transaction=True marker support with table truncation cleanup
• New v2 isolation API (_apply_django_db_isolation_v2, _cleanup_django_db_isolation_v2)
• Proper flush-based cleanup for TransactionTestCase style tests

Connection Management (#22)

• _dispose_all_connections() - Fork-safe connection disposal before snapshots
• _get_database_aliases() - Multi-database iteration helper
• Prevents SSL/MAC errors and stale connection issues after fork

Files Changed

• src/core/config.rs - CLI flags + MergedConfig
• src/core/protocol.rs - IPC protocol fields
• src/tach_harness.py - 10 new database functions (+309 lines)
• New test files in tests/gauntlet_django/

Closed Issues

• Closes #22 - Django Database Support
• Closes #37 - --reuse-db and --create-db CLI flags
• Closes #40 - transaction=True support

Full Changelog: v0.2.5...v0.3.0

v0.2.5

Plugin Stabilization

Final release of the 0.2.x Plugin Compatibility phase.

Features

• Plugin Compatibility Test Suite: Comprehensive tests for all supported plugins
• External Project Tests: Integration tests against FastAPI and real Django projects
• Conftest Parsing Cache: Disk-based cache with SHA-256 content hashing
• Lazy Plugin Loading: Plugin shims loaded on-demand to reduce startup overhead
• Plugin Overhead Benchmarks: Criterion benchmarks for registry operations

Plugin Compatibility Matrix

Plugin	Status
pytest-django	✅ Full Support
pytest-asyncio	✅ Full Support
pytest-mock	✅ Full Support
pytest-env	✅ Full Support
pytest-timeout	✅ Full Support
pytest-xdist	⚡ Superseded (native parallelism)
pytest-cov	⚡ Superseded (PEP 669 coverage)

Phase 2 Complete

This release marks the completion of the Plugin Compatibility phase. Development now moves to Phase 3: Database Integration (0.3.x).

Full Changelog

v0.2.4...v0.2.5

v0.2.4

Landlock V4-V6 Network Isolation (Kernel 6.7+)

Features

• Runtime ABI Detection: detect_landlock_abi() probes ABI V1-V6 at startup
• TCP Bind Restrictions: Per-worker port binding rules via AccessNet::BindTcp
• TCP Connect Restrictions: Outbound connection filtering via AccessNet::ConnectTcp
• Graceful Fallback: Falls back to CLONE_NEWNET or SeccompOnly on older kernels

Configuration

[tool.tach.network]
allow_localhost = true
allow_connect = ["api.example.com:443"]
allow_bind_ports = [8000, 8080]

Full Changelog

v0.2.3...v0.2.4

v0.2.3

Features

Django URL and Template Markers (#35)

• @pytest.mark.urls('myapp.test_urls') - Override ROOT_URLCONF per test
• @pytest.mark.ignore_template_errors - Suppress template errors
• Positional argument extraction in Rust scanner

pytest-mock Support

• Native mocker fixture compatibility via pytest's fixture resolution
• mocker.patch(), mocker.patch.object(), mocker.patch.dict()
• mocker.spy() and mocker.stub() support
• Automatic mock cleanup between tests

pytest-env Support

• {VAR} variable expansion for pytest-env values
• Double braces {{VAR}} escape to literal braces
• Variables expanded from current environment at load time

pytest-timeout Support

• Supervisor-level timeout enforcement via SIGTERM/SIGKILL

pytest-asyncio Improvements

• Fix AsyncioSetup effect conversion in Zygote (#46)
• Event loop scope transition cleanup (#43)
• Proper cleanup for module/class/session scoped loops

Bug Fixes

• #41: Include integration tests in CI
• #42: Use pytest.importorskip() instead of silent pass pattern
• #43: Event loop scope transition cleanup
• #44: Use public properties in EventLoopManager tests
• #45: Add debug logging to cleanup exception handlers
• #46: Handle AsyncioSetup in convert_py_effects_to_rust

Deferred to 0.3.0 (#49)

• transaction=True marker option
• reset_sequences=True marker option
• Multi-database support (databases=[...])

Full Changelog: v0.2.2...v0.2.3

v0.2.2

pytest-asyncio Support

Full async test and fixture support for pytest-asyncio compatibility.

Added

• Async Detection: Track async fixtures throughout the pipeline

  • is_async field in FixtureInfo, FixtureDefinition, ResolvedFixture
  • Async fixture detection based on async def parsing
  • Support for sync tests using async fixtures

• Event Loop Management: Scoped event loop lifecycle

  • EventLoopManager singleton class with function/class/module/session scopes
  • LoopScope enum for loop scope configuration
  • Custom event loop policy support (uvloop integration)
  • Proper loop cleanup and asyncio.run() compatibility

• Marker Support: Full @pytest.mark.asyncio handling

  • loop_scope parameter parsing (function, class, module, session)
  • Automatic async test detection mode
  • AsyncioSetup HookEffect for Rust→Python configuration propagation

• Coroutine Execution: Robust async test execution

  • Async-aware timeout with proper task cancellation
  • TaskGroup and gather cleanup support
  • Nested event loop handling

Changed

• Updated roadmap to mark 0.2.2 as complete (21/21 items)

Full Changelog: v0.2.0...v0.2.2

v0.2.1

pytest-django Support (Core Infrastructure)

Foundation for Django test support with marker-aware database isolation.

Added

• Marker Detection: Static parsing of @pytest.mark.django_db markers

  • Marker arguments extracted during discovery (transaction, reset_sequences, databases)
  • MarkerInfo structure in protocol for IPC propagation
  • Marker-aware test scheduling

• Database Isolation: SAVEPOINT-based transaction rollback

  • DjangoDbSetup HookEffect variant for database configuration
  • _apply_django_db_isolation() in Python harness wraps tests in savepoints
  • _cleanup_django_db_isolation() ensures rollback on success or failure
  • Worker process reuse without database pollution

• Plugin Registry: pytest-django registered as "Supported" plugin

  • Tach shims core pytest-django responsibilities
  • Compatible with zygote/fork execution model

• Integration Tests: Django isolation verification

  • tests/gauntlet_django/ test suite
  • Marker isolation, parallel isolation, savepoint cleanup tests

Not Yet Implemented

The following features are deferred to 0.3.x (Database Integration phase):

• transaction=True argument support
• reset_sequences=True argument support
• Multi-database (databases=[...]) support
• Django fixtures (client, rf, admin_client, live_server, etc.)
• --reuse-db and --create-db CLI flags
• @pytest.mark.urls and @pytest.mark.ignore_template_errors markers

See GitHub issues for tracking.

Full Changelog: v0.2.0...v0.2.1

v0.2.0

Hook Interception Framework

Introduces the complete pytest plugin compatibility system, laying the foundation for seamless integration with the pytest ecosystem.

Added

• Hook Interception Framework: Complete infrastructure for intercepting and replaying pytest hooks
  • Hook discovery in conftest.py files with toxicity integration
  • Conftest inheritance resolution (root-to-leaf hook ordering)
  • Effect recording for pytest_configure (env vars, sys.path modifications)
  • Effect replay in workers before test execution
  • IPC protocol extension with hooks, cached_effects, markers fields in TestPayload
  • Plugin detection and warning system using importlib.metadata
• HookResult type and aggregation strategies: FirstResult, AllResults, NoReturn
• HookCaller with PyO3 bridge: Rust-side hook orchestration
• HookDependencyGraph: Conftest hierarchy ordering (root to leaf)
• PluginRegistry: Plugin status tracking (Supported, Partial, Superseded, Incompatible)
• Plugin configuration: Via pyproject.toml (disabled plugins, priority ordering)
• call_hook_impl(): Python function for loading conftest and calling hooks
• Hook support: pytest_configure, pytest_collection_modifyitems, pytest_runtest_setup/teardown, pytest_runtest_makereport, pytest_sessionfinish
• Hook Registry: Foundation for pytest plugin compatibility
  • HookSpec, Hook, HookEffect types with Serde derives for IPC serialization
  • HookRegistry for tracking discovered hooks
  • builtin_hook_specs() for 10 known pytest hooks
  • file_has_toxic_hooks() for toxicity graph integration
  • resolve_hooks_for_path() for conftest inheritance
  • get_session_effects() for session-level hook effects
• Marker Detection: Extract pytest markers from test decorators
  • Markers included in tach list --json output
  • Markers propagated to workers via TestPayload
  • Excludes decorator-only markers (parametrize, usefixtures, filterwarnings)
• Plugin Detection: Detect installed pytest plugins at startup
  • Warn about unsupported plugins (pytest-parallel, pytest-forked, etc.)
  • Log info about unknown plugins that may or may not work
  • Supported plugins list includes pytest-mock, pytest-env, pytest-randomly, etc.
• Effect Recording: Capture side effects from session-level hooks
  • Environment variable changes (SetEnv effect)
  • sys.path modifications (ModifySysPath effect with prepend/append/remove)
  • Effects transmitted from Zygote to Supervisor to Workers
• Autouse Fixture Detection: Parse autouse=True from @pytest.fixture

Changed

• TestModule now includes hooks field
• TestCase now includes markers field
• FixtureDefinition now includes autouse field
• RunnableTest now includes markers field for worker propagation
• TestPayload now includes hooks, cached_effects, and markers fields
• JsonTestInfo now includes markers field for JSON discovery output
• ToxicityGraph::build() now accepts HookRegistry parameter for hook-based toxicity

Full Changelog: v0.1.5...v0.2.0

v0.1.5

Tooling Integration Research

Completes the 0.1.x Foundation phase with tooling ecosystem documentation, container compatibility research, and developer experience improvements.

Added

• Docker Development Environment: Full containerized dev setup with Dockerfile, docker-compose.yml, VS Code devcontainer.json, and post-create.sh script
• --no-ignore CLI Flag: Bypass .ignore/.gitignore files during test discovery
• .ignore Pattern Warnings: Detect and warn when .ignore patterns block Python file discovery
• Research Documentation: Container compatibility matrix, tooling conflicts analysis, and test discovery edge case catalogue

Changed

• CI Coverage Threshold: Enforced 90% coverage as hard failure
• Golden Tests: Now opt-in via GOLDEN_TESTS=1 environment variable
• MSRV: Updated minimum supported Rust version to 1.88

Fixed

• Python 3.14 Support: Handle immortalization behavior in refcount tests
• Landlock Security: Restrict project_root access, remove excessive /run access, fix symlink escape paths
• CI Stability: Prioritize release binary in tests, fix coverage parsing, add missing test directories

Security

• Restricted Landlock access for project_root (write access only where needed for OverlayFS)
• Removed excessive /run filesystem access from Landlock rules
• Added mknod blocking test for Landlock enforcement

Documentation

• Consolidated research topics into single archive
• Merged errors.md into troubleshooting.md, wsl2-setup.md into quickstart.md
• Added container compatibility research with empirical testing
• Removed volatile data (test counts, line numbers) from documentation

Full Changelog: v0.1.4...v0.1.5

v0.1.4

Foundation Phase Complete

This release consolidates the 0.1.x Foundation phase, completing all planned work:

0.1.1 - Documentation and Polish

• Created examples/ directory with sample projects (simple, django, async, parametrized, markers, conftest)
• Quick-start tutorial in docs/quickstart.md
• Inline code comments for complex algorithms
• CLI improvements (--help, --version --verbose, --dry-run, --collect-only)
• Bug fixes for AST discovery, conftest handling, symlinks, long names

0.1.2 - Test Compatibility

• Full assertion handling (pytest.raises, pytest.warns, pytest.approx, pytest.fail, pytest.skip, pytest.xfail, pytest.importorskip)
• pytest-compatible traceback formatting with --tb=short/long/line/native
• Timeout handling with per-test markers and global configuration
• Worker lifecycle improvements (cleanup, health checks, recycling)

0.1.3 - Error Handling and Diagnostics

• Error categorization (user vs system errors) with codes E001-E020
• --diagnose flag for troubleshooting kernel capabilities
• --debug and --trace flags for verbose logging
• Common failure suggestions with remediation hints

0.1.4 - Dependency Updates

• Updated to Rust 2024 Edition
• PyO3 0.27.2, tokio 1.49, clap 4.5
• Tested against Python 3.10-3.14
• PyPy experimental support documented
• PEP 703 (Free-Threading) research completed

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Note: Versions 0.1.1-0.1.4 were developed in parallel during the Foundation phase.

See CHANGELOG.md for release notes and docs/research/roadmap.md for the complete development roadmap.