Instruction file imported from iammohitsakhuja/excelsior (.github/instructions/testing.instructions.md). Copyright stays with the author.

Copilot Testing Instructions for Excelsior

Project Overview

Excelsior is a Python CLI application for working with Excel and CSV files.

Tools & Configuration

• Python 3.13+
• uv for package management and virtual environment
• pytest with comprehensive configuration in pyproject.toml
• ruff for formatting and linting
• argparse for CLI, dataclasses for structured data
• make commands for development tasks (formatting, linting, testing)

Testing Standards and Conventions

• Follow AAA pattern: Arrange, Act, Assert
• Clear, descriptive test names (e.g., test_cli_fails_on_empty_vault())
• Prefer real data and subprocess in integration tests
• Minimize mocks — only mock I/O, subprocess, or system dependencies
• Group related tests in classes with short docstrings
• Use shared fixtures via conftest.py
• Do not include full project structure in documentation as it's evolving

Integration Test Practices

• Test actual CLI behavior using subprocess
• Use real file I/O for input and output validation
• Avoid mocking in integration tests unless external system behavior must be isolated
• Cover multiple CLI argument combinations and output formats (CSV, JSON, table)

Maintenance Guidelines

• Keep tests self-explanatory and in sync with core application structure
• Maintain test documentation in docs/test-suite.md
• Do not auto-generate summary files — keep documentation minimal and focused