For member under [workspace], Glob pattern doesn’t work for paths whose parent is excluded

[rinarakaki]

Problem

I want to group my related packages managed in the same repository under a directory, for example, libs/group-1 which you can think of as a sub-workspace but not a crate itself (there’s no Cargo.toml for it):

(Project Root)
├── Cargo.toml ([workspace])
├── libs
│   ├── group-1
│   │   ├── lib-1
│   │   │   └── Cargo.toml
│   │   └── lib-2
│   │       └── Cargo.toml
│   ├── lib-3
│   …
│   └── lib-n
…

I want to exclude only the path to it lib/group-1 from members — so Cargo won’t try to find its non-existent Cargo.toml based on the rule libs/* — but still include everything under the directory (libs/group-1/*), hence:

[workspace]
member = [
    "libs/*",
    "libs/group-1/*",
    "libs/group-1/lib-1"  # [1]
]
exclude = [
    "libs/group-1"
]

The problem is this doesn’t work, for example, for lib-2 located at libs/group-1/lib-2.

[1] Here I have added libs/group-1/lib-1 to explain where the intuition comes from, because this config is still valid and does work forlib-1.

Steps

No response

Possible Solution(s)

No response

Notes

No response

Version

No response

[weihanglo]

I had a hard time understanding what you want. Could you provide an example project and clarify what you want to include?

I also forgot the best way to show all workspace members. Maybe this?

cargo tree --workspace --depth 0 -e normal

[rinarakaki]

@weihanglo Thank you for your comment! I have added an example repository tree

[weihanglo]

I see. Thanks for the explanation!

I believe this exclude rule is by design. workspace.exclude. From the chapter Workspaces in The Cargo Book:

The exclude key can be used to prevent paths from being included in a workspace. This can be useful if some path dependencies aren't desired to be in the workspace at all, or using a glob pattern and you want to remove a directory.

The contradictory happens between

• Cargo understands members libs/* as every subdirectory under libs would be included as a member.
• Cargo understands exclude libs/group-1 as removing the directory during probing members. That is, it won't include any path starting from lib/group-1 unless you explicitly set them in members. The code attributing this behaviour resides here.

Cargo aggressively probes Cargo.toml when you use a glob pattern. That is unlucky for your case. #4593 has more discussion and ideas to make Cargo smarter. Ideas around switching to .gitignore pattern also exist (#6009 (comment)). Before any of them proceeding, , reorganizing your project layout is the only suggestion I can give at this moment 😞.

I think both of the issues above cover what you try to resolve. I'd like to close this issue in favor of them. Does this sound good to you?

[epage]

I wish we could just use gitignores for members which would allow both including and excluding on a single field with a very obvious way for them to interact.

[ehuss]

I also forgot the best way to show all workspace members. Maybe this?

cargo metadata | jq .workspace_members is usually the best way.

[weihanglo]

[This is yet resolved]

I am going to close this. Further discussion could happen in #11405. If you think this is wrong please leave a comment. We could reopen it.

Edit: I think it is better to leave it open.