Add GitHub Actions workflow for automated testing (#26)

[mattfsourcecode]

Validation Workflow: Reliable Testing for bootstrapper-script-generator

This pull request introduces an automated GitHub Actions workflow to validate the bootstrapper-script-generator CLI tool, ensuring that the bin command consistently produces valid results with each pull request. The workflow simulates a real-world use case by generating and testing bootstrap scripts based on the project's own structure.

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Benefits

• Automated Validation: Ensures the make-bootstrapper-script command produces functional and consistent output with every update.
• Real-World Testing: Uses the actual project directory as input to reflect realistic scenarios.
• Regression Prevention: Compares the output (test-output) with the source (test-source) to verify correctness.
• Cross-Environment Consistency: Handles file format issues (e.g., line endings, blank lines) to avoid differences across local and CI environments.

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How It Works

1. Environment Setup:

   • Sets up Node.js 20 and pnpm to install dependencies.
   • Builds the project using the pnpm build command.

2. Input Example:

   • Copies the project directory to test-source, excluding unnecessary files (node_modules, .git, etc.).
   • Normalizes file formats to ensure compatibility across environments.

3. Installing the CLI:

   • npm pack: Packages the project as a .tgz file, simulating a published version of the CLI.
   • npm install -g: Installs the packaged .tgz globally to test the bin command (make-bootstrapper-script).

4. Script Generation and Execution:

   • Generates a bootstrap script using the globally installed make-bootstrapper-script command, targeting the test-source directory.
   • Executes the generated script, creating the test-output directory.

5. Validation:

   • Compares test-source and test-output using diff, checking for inconsistencies in structure and content.
   • Normalizes files by removing trailing spaces and ensuring consistent line endings to prevent false-positive differences.

6. Debugging:

   • If differences are detected, logs detailed information about mismatched files, including their hex dumps, for fast troubleshooting.

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Key Features

• Real-World Input: The workflow uses the project itself as input for the bootstrap script, ensuring the generator works as expected with real examples.
• Global Installation Test: By simulating a production installation (npm install -g), the workflow validates the usability of the published package.
• Comprehensive Comparison: Verifies the generated output is an exact match of the input directory structure and content.

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Testing Details

1. Input and Output Comparison:

   • Uses rsync to prepare test-source as the input directory.
   • Runs diff to validate the generated test-output.

2. File Normalization:

   • Removes trailing spaces and blank lines from all files to eliminate discrepancies due to formatting.

3. Debugging Differences:

   • Logs mismatched files and their hex dumps, enabling precise debugging of content-level issues.

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This setup supports a process where a version bump is the last change merged before the updated version is published to npm. This final step adds an additional layer of validation to ensure that the npm package, including any version updates, functions correctly. By testing the package’s functionality in the CI/CD pipeline, it confirms the integrity of the package and verifies that it works as intended before being made publicly available.

Closes #26