New workspace root detected - unexpected pnpm-workspace.yaml

Error message

New workspace root detected - unexpected pnpm-workspace.yaml

What it means

The turbo-gen copy generator rejects copy sources that are themselves monorepo roots. Besides the workspaces field, it treats a pnpm-workspace.yaml at the destination root as proof of a nested monorepo. It throws this Error when that file exists after the copy, then logs it and deletes the copied directory.

Solutions

Copy a single package from inside the pnpm monorepo by setting the example path to that package directory
If you own the source and it is truly a single package, delete or rename the pnpm-workspace.yaml and commit a workspace.yml-free variant
Pick a different example that is not a workspace root

Example fix

# before: copy a pnpm monorepo root
npm exec turbo gen -- --copy https://github.com/org/pnpm-monorepo
# after: copy one workspace from it
npm exec turbo gen -- --copy https://github.com/org/pnpm-monorepo --example-path packages/ui

Defensive patterns

Strategy: validation

Validate before calling

import fs from "node:fs";

// reject copy sources that carry pnpm workspace manifests
if (fs.existsSync(path.join(sourceDir, "pnpm-workspace.yaml"))) {
  throw new Error("Copy source is a pnpm monorepo root; choose one of its packages");
}

Type guard

function isPnpmWorkspaceRoot(dir: string): boolean {
  return fs.existsSync(`${dir}/pnpm-workspace.yaml`);
}

Prevention

Check for pnpm-workspace.yaml when vetting external examples
Copy a single workspace from monorepo examples via the example path
Keep single-package examples free of workspace manifest files

When it happens

Trigger: The external example copied into your monorepo contains a pnpm-workspace.yaml at its root. The existsSync check after the package.json validation finds the file and throws. The generator rolls back the destination directory.

Common situations: Copying a pnpm-based monorepo example instead of one of its packages. An example that ships a pnpm-workspace.yaml for tooling reasons even though it is a single package.

Related errors

AI-assisted analysis of vercel/turborepo@f9245100cf (2026-08-17). Data as JSON: /api/errors/c06a4429cfcce9b7. Report an issue: GitHub.

Appendix: source

Thrown at packages/turbo-gen/src/generators/copy.ts:51

      examplePath: opts.examplePath
    });

    try {
      if (fs.existsSync(newPackageJsonPath)) {
        const packageJson = (await fs.readJSON(
          newPackageJsonPath
        )) as PackageJson;
        if (packageJson.workspaces) {
          throw new Error(
            "New workspace root detected - unexpected 'workspaces' field in package.json"
          );
        }
      } else {
        throw new Error("New workspace is missing a package.json file");
      }

      if (fs.existsSync(path.join(location.absolute, "pnpm-workspace.yaml"))) {
        throw new Error(
          "New workspace root detected - unexpected pnpm-workspace.yaml"
        );
      }
    } catch (err) {
      let message = "UNKNOWN_ERROR";
      if (err instanceof Error) {
        message = err.message;
      }
      logger.error(message);

      // rollback changes
      await fs.rm(location.absolute, { recursive: true, force: true });
      return;
    }
  } else if (source) {
    const filterFunc: CopyFilterAsync = async (src) =>
      !src.includes("node_modules");

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