Temporal Python Testing

When to use this skill

Use Temporal Python Testing when an AI agent needs a reusable SKILL.md workflow for this job: Test Temporal workflows with pytest, time-skipping, and mocking strategies. Covers unit testing, integration testing, replay testing, and local development setup. Use when implementing Temporal workflow tests or debugging test failures.

When not to use it

Skip Temporal Python Testing when the task is outside the coding category, or when a more specific skill in this directory already covers the same workflow with clearer triggers.

How to install

1. Personal install: create ~/.claude/skills/temporal-python-testing/SKILL.md (and any bundled scripts) so Claude Code, Claude Desktop, and compatible agents can load it in every project.
2. Project install: commit the same folder at .claude/skills/temporal-python-testing/ so teammates get the skill with the repo.
3. Restart the agent session after copying files so it re-scans the skills directory, then ask for the task in words that match the skill description.

Full install guide for Claude, Cursor, and Codex

What this skill does

# Temporal Python Testing Strategies

Comprehensive testing approaches for Temporal workflows using pytest, progressive disclosure resources for specific testing scenarios.

## When to Use This Skill

- **Unit testing workflows** - Fast tests with time-skipping - **Integration testing** - Workflows with mocked activities - **Replay testing** - Validate determinism against production histories - **Local development** - Set up Temporal server and pytest - **CI/CD integration** - Automated testing pipelines - **Coverage strategies** - Achieve ≥80% test coverage

## Testing Philosophy

**Recommended Approach** (Source: docs.temporal.io/develop/python/testing-suite):

- Write majority as integration tests - Use pytest with async fixtures - Time-skipping enables fast feedback (month-long workflows → seconds) - Mock activities to isolate workflow logic - Validate determinism with replay testing

**Three Test Types**:

1. **Unit**: Workflows with time-skipping, activities with ActivityEnvironment 2. **Integration**: Workers with mocked activities 3. **End-to-end**: Full Temporal server with real activities (use sparingly)

## Available Resources

This skill provides detailed guidance through progressive disclosure. Load specific resources based on your testing needs:

### Unit Testing Resources

**File**: `resources/unit-testing.md` **When to load**: Testing individual workflows or activities in isolation **Contains**:

- WorkflowEnvironment with time-skipping - ActivityEnvironment for activity testing - Fast execution of long-running workflows - Manual time advancement patterns - pytest fixtures and patterns

### Integration Testing Resources

**File**: `resources/integration-testing.md` **When to load**: Testing workflows with mocked external dependencies **Contains**:

- Activity mocking strategies - Error injection patterns - Multi-activity workflow testing - Signal and query testing - Coverage strategies

### Replay Testing Resources

**File**: `resources/replay-testing.md` **When to load**: Validating determinism or deploying workflow changes **Contains**:

- Determinism validation - Production history replay - CI/CD integration patterns - Version compatibility testing

### Local Development Resources

**File**: `resources/local-setup.md` **When to load**: Setting up development environment **Contains**:

- Docker Compose configuration - pytest setup and configuration - Coverage tool integration - Development workflow

## Quick Start Guide

### Basic Workflow Test

```python import pytest from temporalio.testing import WorkflowEnvironment from temporalio.worker import Worker

@pytest.fixture async def workflow_env(): env = await WorkflowEnvironment.start_time_skipping() yield env await env.shutdown()

@pytest.mark.asyncio async def test_workflow(workflow_env): async with Worker( workflow_env.client, task_queue="test-queue", workflows=[YourWorkflow], activities=[your_activity], ): result = await workflow_env.client.execute_workflow( YourWorkflow.run, args, id="test-wf-id", task_queue="test-queue", ) assert result == expected ```

### Basic Activity Test

```python from temporalio.testing import ActivityEnvironment

async def test_activity(): env = ActivityEnvironment() result = await env.run(your_activity, "test-input") assert result == expected_output ```

## Coverage Targets

**Recommended Coverage** (Source: docs.temporal.io best practices):

- **Workflows**: ≥80% logic coverage - **Activities**: ≥80% logic coverage - **Integration**: Critical paths with mocked activities - **Replay**: All workflow versions before deployment

## Key Testing Principles

1. **Time-Skipping** - Month-long workflows test in seconds 2. **Mock Activities** - Isolate workflow logic from external dependencies 3. **Replay Testing** - Validate determinism before deployment 4. **High Coverage** - ≥80% target for production workflows 5. **Fast Feedback** - Unit tests run in milliseconds

## How to Use Resources

**Load specific resource when needed**:

- "Show me unit testing patterns" → Load `resources/unit-testing.md` - "How do I mock activities?" → Load `resources/integration-testing.md` - "Setup local Temporal server" → Load `resources/local-setup.md` - "Validate determinism" → Load `resources/replay-testing.md`

## Additional References

- Python SDK Testing: docs.temporal.io/develop/python/testing-suite - Testing Patterns: github.com/temporalio/temporal/blob/main/docs/development/testing.md - Python Samples: github.com/temporalio/samples-python

Intended uses

• Unit testing workflows - Fast tests with time-skipping
• Integration testing - Workflows with mocked activities
• Replay testing - Validate determinism against production histories
• Local development - Set up Temporal server and pytest
• CI/CD integration - Automated testing pipelines
• Coverage strategies - Achieve ≥80% test coverage