How to revert from pnpm to npm

When you need to switch back from using pnpm to npm, you can achieve this by following these steps:

1. Clean up existing dependencies and lock files

Since pnpm uses the pnpm-lock.yaml file while npm uses the package-lock.json file, you first need to prune the existing dependencies and remove the lock files. Execute in the project root directory:

bash
pnpm store prune
rm -rf node_modules pnpm-lock.yaml

2. Initialize npm lock files and node modules

Next, install dependencies using npm, which will create the node_modules directory and package-lock.json file.

bash
npm install

This command installs dependencies based on the dependencies specified in package.json and creates a new package-lock.json lock file.

3. Verify the project

After installing dependencies, ensure the application or project runs correctly:

bash
npm run test  # Run tests to verify project functionality

Or run the project to ensure all functionalities work correctly:

bash
npm start  # This depends on the specific start script configuration

4. Commit changes to the version control system

If you are using version control (e.g., git), remember to commit changes. This includes the deleted pnpm-lock.yaml and newly added package-lock.json, as well as possible updates to node_modules:

bash
git add package-lock.json
git rm pnpm-lock.yaml
git commit -m "Switch from pnpm to npm"
git push

Example

Suppose you previously used pnpm to manage a Node.js project, and now due to certain compatibility or team policy reasons, you need to switch back to npm. Follow the steps above: first prune the pnpm lock files and node modules, then use npm install to recreate the npm lock file and download dependencies. After completing these steps, run tests in the project to ensure everything functions correctly, and finally commit these changes to the version control system.

This process ensures a smooth transition from pnpm to npm while maintaining project stability and dependency consistency.

First, I recognize that your question concerns how to transition from using pnpm to npm for package management. This could be for various reasons, such as project requirements or compatibility issues.

Conversion Steps

1. Clean up old package files

   • In the project directory, first remove the node_modules folder and pnpm-lock.yaml file (if present).

bash
rm -rf node_modules
rm -f pnpm-lock.yaml

1. Create or update the npm lock file

   • Since pnpm and npm use different lock file formats, you need to generate a new package-lock.json file. This can be done by running npm install.

bash
npm install

This command will read package.json and regenerate the node_modules folder and package-lock.json file based on the dependencies specified.

1. Verify dependencies

   • After the conversion, ensure all dependencies are properly installed without any missing or version conflicts.

bash
npm list

This command allows you to view the installed dependencies and their versions, confirming that everything is working as expected.

1. Test the project

   • After confirming all dependencies are correctly installed, run the project's tests to ensure everything functions properly.

bash
npm test

This step is crucial because even if dependencies are correctly installed, new issues may arise in the code due to version differences or other reasons.

Important Notes

• During the conversion process, you may encounter issues with incompatible dependency versions, requiring careful inspection and debugging.

• It is recommended to back up the existing project before performing this operation to prevent unexpected issues.

Example

Assume we have a simple project using pnpm, with the following structure:

plaintext
/my-project
  /node_modules
  package.json
  pnpm-lock.yaml

Following these steps, we can convert it to use npm, ensuring the project runs correctly under the new package manager.

Conclusion

By following these steps, we can smoothly transition from pnpm to npm, although this may require some manual checks and adjustments. Adhering to the correct process can minimize migration risks. I hope this helps you complete the required conversion.

Understanding various package managers and their interoperability is important. Switching from pnpm to npm involves the following main steps:

Step 1: Clean up the pnpm environment

First, ensure that you delete or clear the node_modules folder and pnpm-lock.yaml file created by pnpm. This is because pnpm and npm handle dependencies and lock files differently, and using them directly may cause conflicts or errors.

bash
rm -rf node_modules
rm pnpm-lock.yaml

Step 2: Initialize npm

If the project does not have a package.json file (which typically does not occur unless it's a new project), run npm init to create one. If a package.json file already exists, proceed directly to the next step.

bash
npm init

Step 3: Install dependencies

Use npm to install the required dependencies for the project. If a package.json file exists, npm will install all listed dependencies based on it.

bash
npm install

This command creates a node_modules folder and a package-lock.json file, which npm uses to lock dependency versions.

Step 4: Test the project

After the conversion is complete, run the project's tests to verify that all dependencies are correctly installed and the project runs normally.

bash
npm test

Example

Suppose I previously managed a Node.js project using pnpm, which depends on Express and React. During the conversion process, I would first delete the lock file and node_modules folder created by pnpm, then reinstall dependencies using npm, and ensure all tests pass.

This process ensures a smooth transition between package managers while maintaining the project's stability and consistency.

Conclusion

Although pnpm provides excellent performance and disk space optimization, some teams or projects may require consistent use of npm. These steps can help achieve a seamless transition from pnpm to npm.