Add tox for consistent testing across environments

- Added tox.ini with comprehensive test environments (py3.8-3.12, lint, type-check, integration)
- Updated GitHub Actions CI to use tox instead of direct pytest/uv calls
- Configured tox to use uv for fast dependency management (uv-venv-runner)
- Added tox to development dependencies in pyproject.toml
- Updated README with tox usage examples and explanation
- Environment variables properly set to disable color output in CI

This ensures consistent test environments between local development and CI,
eliminating the formatting assertion issues we were experiencing.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: ritwik-g

.github/workflows/ci.yml

@@ -38,23 +38,17 @@ jobs:
       with:
         version: "0.5.14"
 
-    - name: Install dependencies
+    - name: Install tox
       run: |
-        uv sync --all-extras --dev
+        pip install tox tox-uv
 
-    - name: Run unit tests
+    - name: Run tests with tox
       run: |
-        uv run pytest tests/ -v --cov=helm_values_manager --cov-report=xml --cov-report=term
-      env:
-        FORCE_COLOR: "0"
-        NO_COLOR: "1"
+        tox -e py${{ matrix.python-version }}
 
-    - name: Run integration tests
+    - name: Run integration tests with tox
       run: |
-        uv run pytest tests/test_integration.py -v
-      env:
-        FORCE_COLOR: "0"
-        NO_COLOR: "1"
+        tox -e integration
 
     - name: Upload coverage to Codecov
       if: matrix.os == 'ubuntu-latest' && matrix.python-version == '3.12'
@@ -85,26 +79,18 @@ jobs:
       with:
         python-version: '3.12'
 
-    - name: Install uv
-      uses: astral-sh/setup-uv@v5
-      with:
-        version: "0.5.14"
-
-    - name: Install dependencies
-      run: |
-        uv sync --all-extras --dev
-
-    - name: Run ruff check
+    - name: Install tox
       run: |
-        uv run ruff check .
+        pip install tox
 
-    - name: Run ruff format check
+    - name: Run linting with tox
       run: |
-        uv run ruff format --check .
+        tox -e lint
 
-    - name: Run mypy
+    - name: Run type checking with tox
       run: |
-        uv run mypy helm_values_manager --ignore-missing-imports || true
+        tox -e type-check
+      continue-on-error: true
 
   plugin-test:
     runs-on: ubuntu-latest

README.md

@@ -310,16 +310,59 @@ This plugin is written in Python and uses:
 - **CLI Framework**: Typer
 - **Dependencies**: PyYAML for YAML generation
 - **Testing**: pytest with comprehensive test coverage
+- **Testing Tool**: tox for consistent testing across environments
 
 ### Building from Source
 
 ```bash
 git clone https://github.com/Zipstack/helm-values-manager
 cd helm-values-manager
-uv install
-uv run pytest  # Run tests
+uv sync  # Install dependencies
 ```
 
+### Running Tests
+
+We use tox for consistent testing across different Python versions and environments:
+
+```bash
+# Run tests for current Python version
+tox
+
+# Run tests for specific Python version
+tox -e py311
+
+# Run linting
+tox -e lint
+
+# Run type checking
+tox -e type-check
+
+# Run integration tests
+tox -e integration
+
+# Run all environments
+tox -p  # parallel execution
+```
+
+### Alternative: Direct pytest (for development)
+
+```bash
+# Using uv
+uv run pytest
+
+# Using pip
+pip install -e .[dev]
+pytest
+```
+
+### Why Tox?
+
+Tox ensures consistent test environments between local development and CI:
+- Isolated virtual environments for each test run
+- Consistent dependency installation
+- Environment variable standardization
+- Cross-platform compatibility
+
 ## Contributing
 
 1. Fork the repository