`disallowed_methods` on trait impls

[Jarcho]

Description

It should be possible to to specify a specific impl of a trait method (e.g. <alloc::vec::Vec as core::iter::IntoIterator>::into_iter) to be disallowed, rather than having to disallow the trait method for all impls. Two things will need to be done to fix this:

• clippy.toml syntax will need to be extended.
• The DefId for the trait method will need to be resolved to it's impl's DefId, if possible (generic code will need something more creative here as it could be calling <T as IntoIterator>::into_iter).

@rustbot label +E-medium
@rustbot label +C-enhancement

[DevAccentor]

@rustbot claim

[safinaskar]

I agree this would be a good feature. There are many ways to copy a string (a.to_owned(), a.clone(), a.to_string()). This lint will allow us to enforce particular way

[Emilgardis]

Is this still being worked on? @DevAccentor