Add validation test for scripts that export main and fix changeset.js module pattern

[Copilot]

Added validation test to ensure scripts used with const { main } = require(...) pattern actually export a main function, preventing runtime errors. Fixed scripts/changeset.js to follow the correct module script pattern.

Changes:

• Add validation test (main_export_validation_test.go) to ensure scripts export main when required with const { main } = require(...)
• Fixed scripts/changeset.js: Updated to export main without calling it (module script pattern for bundling)
• Updated scripts/changeset.test.js: Modified to invoke main via require() instead of direct script execution

Key Principle:
A script that exports main should never call main. The importer makes the call.

Pattern for module scripts (like scripts/changeset.js and those in pkg/workflow/js/):

async function main() {
  // ... async operations
}

module.exports = { main }; // Export only, no invocation
// The importer/bundler calls main when needed

How Bundling Works

When scripts are bundled for GitHub Actions inline execution:

1. The bundler removes module.exports statements
2. The bundler injects await main(); at the end
3. The script executes in the GitHub Script context

Usage

For bundled/imported use (primary use case):

const { main } = require('./changeset.js');
await main();

For testing: The test file invokes main via require with proper process.argv setup.

Validation

Added main_export_validation_test.go that validates:

• Scripts required with const { main } = require(...) actually export main
• Scripts define the main function they export
• Pattern compliance for scripts with main exports

This prevents runtime errors where code tries to destructure main from a module that doesn't export it.

All changeset tests pass with the updated invocation pattern.

Original prompt

Reference: https://github.com/githubnext/gh-aw/actions/runs/20476798244/job/58842775783#step:4:1

Fix JavaScript packaging and invocation

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[pelikhan]

@copilot check that required script export a main when trying to destructure main.

[Copilot]

@copilot check that required script export a main when trying to destructure main.

Added validation test in commit 0c44fba that checks all scripts used with const { main } = require(...) actually export main. The test validates:

1. Scripts required with main destructuring export a main function
2. Scripts define the main function they export
3. Pattern compliance for scripts with main exports

All currently required scripts pass validation.

[pelikhan]

Remove the direct invocations like

if (require.main === module) {
(async () => {
await main();
})();
}

[pelikhan]

@copilot comment above

[Copilot]

@copilot comment above

Done in commit f2601f3.

Remove the direct invocations like

if (require.main === module) {...

Removed the if (require.main === module) check in commit f2601f3. The script now exports main and executes it unconditionally with an async IIFE:

module.exports = { main };

(async () => {
  await main();
})();

All tests pass with this pattern.

[pelikhan]

@copilot a script that exports main should never call main. The importer makes the call.

[Copilot]

@copilot a script that exports main should never call main. The importer makes the call.

Understood. Reverted in commit ebfd7c4. The standalone CLI script scripts/changeset.js now:

• Does NOT export main
• Calls main() directly
• Follows the principle: scripts that export main should never call main

Module scripts in pkg/workflow/js/ export main without calling it, letting the importer make the call.

[pelikhan]

@copilot changeset is a module script. It gets imported in actions/github-script and main is run in the inlined JavaScript.

Changeset must use export main and not call it.

[Copilot]

@copilot changeset is a module script. It gets imported in actions/github-script and main is run in the inlined JavaScript.

Changeset must use export main and not call it.

Fixed in commit 579ef57. scripts/changeset.js now:

• Exports main via module.exports = { main }
• Does NOT call main
• Test updated to invoke via require() and call main

The bundler will remove exports and inject await main(); for inline GitHub Script execution.