chore(test-project): Prepare for fully switching to ESM

[Tobbe]

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☁️ Nx Cloud last updated this comment at 2026-01-04 14:11:53 UTC

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☁️ Nx Cloud last updated this comment at 2026-01-04 13:57:49 UTC

[greptile-apps]

Greptile Summary

Converts test-project maintenance scripts from CommonJS to ESM by renaming .js/.ts files to .mts, updating all imports to use .mjs extensions, and adding proper TypeScript types throughout. The conversion is part of a larger effort to fully switch the test-project tooling to ESM.

Key changes:

• Renamed 10+ files from .js/.ts to .mts for ESM compatibility
• Updated all relative imports to use .mjs extensions (required for Node.js ESM)
• Added __filename and __dirname polyfills using fileURLToPath and path.dirname
• Converted CommonJS require() to ESM import statements
• Replaced module.exports with named export statements
• Added TypeScript type annotations throughout (string, boolean, ExecaOptions, etc.)
• Updated package.json scripts to reference .mts files and use tsx consistently
• Added exclude for test-project/templates in tasks/tsconfig.json to prevent TypeScript errors
• Removed @ts-nocheck comments from codemod files as part of cleanup

Files needing attention:

• tasks/test-project/frameworkLinking.mts: The execa call syntax changed from string to array format - verify this works correctly with shell: true option

Confidence Score: 4/5

• This PR is safe to merge with minor verification recommended
• The ESM conversion is well-executed with proper TypeScript types and consistent patterns throughout. One minor concern is the execa API change in frameworkLinking.mts (string to array syntax) which should be verified to work correctly with shell: true, but this is likely correct usage. All other changes follow best practices for ESM migration.
• Pay attention to tasks/test-project/frameworkLinking.mts - verify the execa array syntax works with shell:true option

Important Files Changed

Filename	Overview
tasks/test-project/frameworkLinking.mts	Converted from CommonJS to ESM with proper TypeScript types; however, execa call changed from string to array syntax which may behave differently with shell: true
tasks/test-project/util.mts	Converted to ESM with new module-level state management functions (setOutputPath, setVerbose) and proper TypeScript typing throughout
tasks/test-project/tasks.mts	Large conversion from JS to TypeScript ESM with proper imports, type annotations, and improved error handling
package.json	Updated script paths to use .mts extensions and changed build:test-project to use tsx for consistency with other scripts
tasks/tsconfig.json	Added exclude for test-project/templates directory to prevent TypeScript from processing template files

Sequence Diagram

sequenceDiagram
    participant Dev as Developer
    participant Scripts as NPM Scripts
    participant TSX as TSX Runtime
    participant Utils as util.mts
    participant Tasks as tasks.mts
    participant Framework as frameworkLinking.mts
    participant Execa as execa
    
    Dev->>Scripts: yarn build:test-project
    Scripts->>TSX: tsx test-project.mts
    TSX->>Tasks: import { apiTasks, webTasks }
    Tasks->>Utils: import { getExecaOptions, exec }
    Tasks->>Framework: (optional) import for linking
    
    Note over Tasks,Utils: ESM imports now use .mjs extensions
    
    Tasks->>Utils: getExecaOptions(path)
    Utils-->>Tasks: ExecaOptions
    
    Tasks->>Execa: execa(cmd, args, options)
    Note over Tasks,Execa: Array syntax with shell:true
    
    Framework->>Execa: execa('yarn', ['project:deps'], options)
    Note over Framework,Execa: Changed from string to array syntax
    
    Execa-->>Framework: Process result
    Framework-->>Tasks: Completion
    Tasks-->>TSX: Task execution complete
    TSX-->>Scripts: Build complete

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[greptile-apps]

_{15 files reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

style: changed from execa('yarn project:deps', options) (string command) to execa('yarn', ['project:deps'], options) (array syntax). verify this behaves the same with shell: true

Prompt To Fix With AI

This is a comment left during a code review.
Path: tasks/test-project/frameworkLinking.mts
Line: 19:19

Comment:
**style:** changed from `execa('yarn project:deps', options)` (string command) to `execa('yarn', ['project:deps'], options)` (array syntax). verify this behaves the same with `shell: true`

How can I resolve this? If you propose a fix, please make it concise.

[Tobbe]

@greptileai A lot of the changes in this PR have already been merged to main as part of other PRs. On a high level, is there anything done in this PR that isn't already on main, and if so, what? Or is it safe to close this PR?

[greptile-apps]

Based on my analysis, this PR appears to be largely redundant. Here's what I found:

Already merged to main:

1. ESM conversion is complete: All the key files like tasks.mts, frameworkLinking.mts, util.mts, etc. already exist in their ESM form with TypeScript types

2. Package.json scripts already updated: The scripts that were changed in this PR are already using tsx instead of node:

   • ✅ "build:test-project": "tsx ./tasks/test-project/test-project.mts"
   • ✅ "rebuild-test-project-fixture": "tsx ./tasks/test-project/rebuild-test-project.mts"
   • ✅ "rebuild-test-project-fixture-esm": "tsx ./tasks/test-project/rebuild-test-project-fixture-esm.mts"

3. Import statements updated: The files I checked already have proper ES6 imports and .mjs extensions in import paths

4. TypeScript types added: Proper TypeScript interfaces and type annotations are already present

What this PR was trying to accomplish:

• Convert CommonJS modules to ESM modules (.js → .mts)
• Add TypeScript type annotations
• Update import/export statements
• Update package.json scripts to use tsx
• Add ESM-specific polyfills like __filename and __dirname

Conclusion:

Yes, it's safe to close this PR. All the ESM conversion work that this PR was attempting to do has already been completed and merged to main through other PRs. The current state of main already has the fully converted ESM test-project scripts with proper TypeScript types.