Support workspaces

[jwodder]

The following is a list of changes that will need to be made in order for rsrepo to properly support Cargo workspaces:

• rsrepo new:

  • Add an option for creating a workspace
  • The test.yml template should be adjusted for creating a workspace
    • Pass --workspace to all(?) cargo commands?

• rsrepo mkgithub: When run in a workspace, the behavior should depend on whether there is a root package:

  • If there is a root package, use its metadata the same way a non-workspace package's metadata is currently used.
  • If the workspace is virtual:
    • Fetch the description & keywords to apply to the GitHub repository from the [workspace.package] table
      • Getting these fields will require parsing the root Cargo.toml directly, as they do not seem to be directly reported by cargo metadata
      • In many cases, these fields will not be set on the workspace level; what should happen then?
    • If no repository name is specified on the command line, parse the name from the workspace.package.repository field in the root Cargo.toml file, erroring if there is none
    • Look for a "WIP" repostatus badge in a README.md in the root of the workspace
    • After creating the GitHub repository, update the workspace.package.repository field if it is unset, or warn if it differs from the GitHub repository's URL

• rsrepo release:

  • Add an option for specifying which packages to release
    • When this option is not given and running inside a package's directory, release that package
  • When releasing multiple packages at once, should a single commit with all necessary changes be made, or should there be one commit per package?
  • When releasing a breaking version of a package, update the version requirements of all other packages in the workspace that depend on it
    • Look into how cargo-release identifies such dependents
  • When publishing multiple packages that depend on each other, dependencies will need to be published before dependents
  • When running in a workspace, tags for non-root packages need to include the package name in some form
    • cargo-dist currently (as of v0.0.7) requires package-specific tags to be in the form {package_name}-v{version}.
  • Fetching a package's lastest tag will need to be done by filtering by package
  • When running in a workspace (and when releasing a non-root package?), include the package name in the intended subject line of the commit message template
  • cf. cargo-release

• rsrepo set-msrv: Add an option for specifying which packages to operate on

  • Should there be an option for editing [workspace.package.rust-version]?

• The code for locating a package and getting its metadata will need to be updated to work in a workspace with (or without?) specific package names specified on the command line

• Ideally, a subcommand should be added for templating a new package in a workspace

  • The templated package should contain a LICENSE symlink pointing to the workspace's LICENSE
  • If the new package is not already matched by a glob in workspace.members, it should be added to the list