Renaming a trait method fails to rename method on trait impls

[ZoeyR]

When invoking rename on a method call to a trait method the language server will not have workspace edits for implmentations of the trait, only the trait definitions and invocations of the function. See below for example code and the parameters sent between the client and the server.

Example Code:

use foo::Baz;

pub fn use_bar() {
    let _ = foo::Bar.baz();
}

mod foo {
    pub struct Bar;

    pub trait Baz {
        fn baz(&self);
    }

    impl Baz for Bar {
        fn baz(&self) {
        }
    }
}

Params sent from client to server

{
    "textDocument": {
        "uri": "file:///C:/my/home/Documents/rust-lsp-tests/src/lib.rs"
    },
    "position": {
        "line": 3,
        "character": 22
    },
    "newName": "buzz"
}

Params sent from server to client:

{
    "changes": {
        "file:///C:/my/home/Documents/rust-lsp-tests/src/lib.rs": [
            {
                "range": {
                    "start": {
                        "line": 10,
                        "character": 11
                    },
                    "end": {
                        "line": 10,
                        "character": 14
                    }
                },
                "newText": "buzz"
            },
            {
                "range": {
                    "start": {
                        "line": 3,
                        "character": 21
                    },
                    "end": {
                        "line": 3,
                        "character": 24
                    }
                },
                "newText": "buzz"
            }
        ]
    },
    "documentChanges": null
}

[nrc]

We should block these renames in the same way we do with fields using field init sugar, etc.

[algesten]

I've started looking at this. Here's a test case in rls-analysis that does what the rename request does in RLS.

rust-dev-tools/rls-analysis@ab863c5

This may or may not be related to https://internals.rust-lang.org/t/rustdoc2-rls-analysis-and-the-compiler-help-wanted/6592/5

find_impls() currently returns spans for the rows with impl Baz for Bar, which isn't particularly helpful when trying to navigate from def to trait. Next step is probably to understand whether the changes @nrc posted about indeed are enough to support this case. I think it is.