• I'd be willing to implement this feature (contributing guide)

Describe the solution you'd like

I think that pnpm add tree-utils should default to "tree-utils": "workspace:^" instead of "tree-utils": "workspace:^1.0.0" because it's safer. Or provide a setting complementary to save-prefix to allow specifying how workspace versions should be saved.

For instance, two settings could be introduced: save-workspace-prefix (fallbacks to save-prefix, default ^) and save-workspace-version (default rolling).

save-workspace-prefix    save-workspace-version        package.json#dependencies
                                'any'                     *
        ''                      'none'                    1.0.0
        '^'                     'none'                    ^1.0.0
        '~'                     'none'                    ~1.0.0
        ''                      'current'                 workspace:1.0.0
        '^'                     'current'                 workspace:^1.0.0
        '~'                     'current'                 workspace:~1.0.0
        ''                      'rolling'                 workspace:*
        '^'                     'rolling'                 workspace:^
        '~'                     'rolling'                 workspace:~

Describe the user story

This story shows why I think rolling is safer

Let's create a repository with the following two packages

• my-pkg @ 1.0.0
  -> tree-utils @ 1.0.0, exports { root, leaf }

After both packages are created, add the following dependency

cd packages/my-pkg
pnpm add tree-utils

{
  "name": "my-pkg",
  "dependencies": {
    "tree-utils": "workspace:^1.0.0"
  }
}

After a few weeks, add a feature to my-pkg which requires a new export named branch from tree-utils. No problem, just release a new minor version of both my-pkg and tree-utils.

• my-pkg @ 1.1.0
  -> tree-utils @ 1.1.0, exports { root, leaf, branch }

{
  "name": "my-pkg",
  "dependencies": {
    "tree-utils": "workspace:^1.0.0"
  }
}

Notice that no dependencies were updated, pnpm automatically resolves "tree-utils": "workspace:^1.0.0" to tree-utils@1.1.0 which is the version in the workspace. All tests and prerelease checks are ok because they are using the latest tree-utils available in the workspace. But when this package is published, it's not guaranteed that this will be the case. After publishing, another package manager or bundler could resolve "tree-utils": "^1.0.0" to tree-utils@1.0.0 (e.g. to avoid duplicated dependencies when another package has a dependency on "tree-utils": "~1.0.0"). This will result in a runtime error since my-pkg requires a version of tree-utils that exports branch and only tree-utils@1.1.0 is capable of it.

The problem is that workspace:^1.0.0 is set in stone and not updated. If pnpm used workspace:^ by default, then my-pkg@1.1.0 would have been published with a dependency on "tree-utils": "^1.1.0" which is safe because that semver range never lags behind and its lower bound is always tested by the pre-release checks.

Describe the drawbacks of your solution

• Slightly higher maintenance burden
• Changes could be backwards incompatible (unless save-workspace-version defaults to current)