disallowed_methods for different versions of dependency without allow-invalid

[asasine]

I'm trying to add disallowed-methods to a clippy.toml in a workspace. The workspace uses multiple versions of a dependency, and an API path changed between the versions, so the resulting TOML looks similar to this:

disallowed-methods = [
    { path = "foo::Bar::baz" }, # crate foo v1 exports Bar at the crate root
    { path = "foo::bar::Bar::baz" }, # crate foo v2 exports Bar from the bar module
]

This generates warnings on one of the items, usually the newer version

`foo::bar::Bar::baz` does not refer to a reachable function

The workaround is to add allow-invalid = true, but this means I don't get the warning if I did accidentally write the wrong path.

How do I write the fully qualified path for foo@1::Bar::baz and foo@2::bar::Bar::baz such that Clippy understands without allow-invalid = true?

[ShreeChaturvedi]

You can't. Clippy has no versioned path form like foo@1::…. Paths are plain crate::module::Item.

Use both layouts and set allow-invalid = true:

disallowed-methods = [
    { path = "foo::Bar::baz", allow-invalid = true },
    { path = "foo::bar::Bar::baz", allow-invalid = true },
]

Clippy runs per crate. A package that only depends on foo v1 never sees the v2 path, so it warns unless you allow invalid. Same the other way for v2-only packages. The ban still applies when the path does resolve.

Related: #17006

Pitfall: Cargo renames do not help. Clippy matches the crate's real name, not the alias.

Version pinning in config would need a Clippy feature request.

[asasine]

Losing the utility of allow-invalid = false is not great, especially since this clippy.toml is in a workspace with dozens of packages, sometimes with different versions of the same dependencies, and so both paths are used, just not within the same workspace package.