clippy handles vendored dependencies differently from crates.io dependencies

[ericseppanen]

Summary

I have noticed that one of my dependencies has compiler warnings. This doesn't usually affect how I use Clippy, because those warnings are suppressed.

However, when I tried to vendor that dependency (checking it in to git in a path outside my project [^1], and changing Cargo.toml to use some_crate = { path = "../vendored/that_crate" }), I find that now Clippy is reporting the compiler warnings from inside that dependency.

I have searched for similar reports of this problem, but didn't see any. #3025 seems possibly related, but doesn't address this issue directly.

[^1]: I've tried this with and without a cargo workspace, and get the same result.

[^2]: To get the vendored copy: git clone -b v0.0.14 https://github.com/nbigaouette/onnxruntime-rs.git

Reproducer

I started a new project, and specified the same dependency in 3 different ways.[^2] Only with the third one (vendored to a local path) does clippy report that crates' warnings when running cargo clippy from within my project.

[dependencies]
# No warnings from clippy if I do this
#onnxruntime = "0.0.14"

# No warnings from clippy if I do this
#onnxruntime = { git = "https://github.com/nbigaouette/onnxruntime-rs.git", tag = "v0.0.14" }

# Clippy prints warnings if I do this
onnxruntime = { path = "../vendored/onnxruntime-rs/onnxruntime" }

Version

rustc 1.63.0 (4b91a6ea7 2022-08-08)
binary: rustc
commit-hash: 4b91a6ea7258a947e59c6522cd5898e7c0a6a88f
commit-date: 2022-08-08
host: x86_64-unknown-linux-gnu
release: 1.63.0
LLVM version: 14.0.5

Additional Labels

No response

[ericseppanen]

cargo check has the same behavior. Perhaps this is a dupe of cargo bug #8546?

[Alexendoo]

It is behaviour from cargo yeah, it's which crates RUSTC_WORKSPACE_WRAPPER apply to.

For vendoring dependencies usually [source] is used (as output by cargo vendor), but on the clippy side if you do want to ignore path dependencies/workspace members --no-deps should work

[ericseppanen]

... on the clippy side if you do want to ignore path dependencies/workspace members --no-deps should work

That doesn't work in this case because the warnings are actually compiler warnings, not clippy lints. Feel free to try the "reproducer" example above to demonstrate this.

[ericseppanen]

Closing in favor of cargo bug #8546.