Allow vendoring of path dependencies

[stevenroose]

Problem

I have a path dependency (crate-name = { path = "/some/local/dir" }) in my Cargo.toml and when I run cargo vendor, it doesn't show up in the vendor directory, so when I export the current directory, that crate is unaccounted for.

Steps

1. create a crate dep1 in ~/tmp/dep1
2. create a crate project1 in ~/tmp/project1
3. add dep1 = { path = "../dep1" } to ~/tmp/project1/Cargo.toml's dependency section
4. go into ~/tmp/project1
5. run cargo vendor

Possible Solution(s)

Don't make a special exception for path dependencies when vendoring.

Notes

No response

Version

cargo 1.49.0 (d00d64df9 2020-12-05)

[weihanglo]

Similar issue: #9172

Seems that cargo-vendor skips path dependency at this moment.

cargo/src/cargo/ops/vendor.rs

Lines 146 to 150 in 8032ac5

	// No need to vendor path crates since they're already in the
	// repository
	if pkg.source_id().is_path() {
	continue;
	}

[ehuss]

Can you share some more details about your use case?

Cargo does not support source replacement of path dependencies, so just including path dependencies in the vendor directory won't help.

[hbina]

I am working on a project where I need to make a lot of little changes to many crates that I use. I also would like to test them out in various environemnt (Windows, Linux, MacOS). So it is desirable to be able to simply checkin all these changes.

I thought I was able to do this:

1. Work on crate A which depends on crate B.
2. Notice I need to make a change on crate B.
3. Create a local copy of B.
4. Vendor crate B, check in the code.
5. Checkout the commit in other environments to test them out.

I could have cloned each crates individually, checkout the specific branch, and coordinate all this.

I am not sure why cargo is making that choice on my behalf?

[stevenroose]

I proposed #12858 to solve this issue.

[weihanglo]

Hi. @hbina I don't quite get the case you share. Do you have a sample project or Cargo.toml to demo?

As I understand it, you want to vendor every change of you path dependencies, and share it across different machines to test it. If your project is under git control, is it possible to just create a git branch containing those change?

@stevenroose could you share the use case or workflow of why you want path dependencies also are exported s vendored source?