Request textDocument/inlayHint fails with request handler panicked: already borrowed: BorrowMutError

[Tyrubias]

When I hover over a broken derive macro in the RustPython codebase, rust-analyzer reports the errors Request textDocument/semanticTokens/full failed and Request textDocument/inlayHint failed. In the rust-analyzer output logs, I see that the request handler panics with the message already borrowed: BorrowMutError.

This error is triggered on this particular line.

Please let me know if I can provide any other details. I'd love to help contribute to this project.

Here are the full output logs

Panic context:
> 
version: 0.3.1186-standalone (e8e598f64 2022-08-28)
request: textDocument/codeAction CodeActionParams {
    text_document: TextDocumentIdentifier {
        uri: Url {
            scheme: "file",
            cannot_be_a_base: false,
            username: "",
            password: None,
            host: None,
            port: None,
            path: "/Users/vsong/Downloads/fun/RustPython/wasm/lib/src/js_module.rs",
            query: None,
            fragment: None,
        },
    },
    range: Range {
        start: Position {
            line: 557,
            character: 13,
        },
        end: Position {
            line: 557,
            character: 22,
        },
    },
    context: CodeActionContext {
        diagnostics: [
            Diagnostic {
                range: Range {
                    start: Position {
                        line: 557,
                        character: 13,
                    },
                    end: Position {
                        line: 557,
                        character: 22,
                    },
                },
                severity: Some(
                    Error,
                ),
                code: Some(
                    String(
                        "E0277",
                    ),
                ),
                code_description: Some(
                    CodeDescription {
                        href: Url {
                            scheme: "https",
                            cannot_be_a_base: false,
                            username: "",
                            password: None,
                            host: Some(
                                Domain(
                                    "doc.rust-lang.org",
                                ),
                            ),
                            port: None,
                            path: "/error-index.html",
                            query: None,
                            fragment: Some(
                                "E0277",
                            ),
                        },
                    },
                ),
                source: Some(
                    "rustc",
                ),
                message: "`std::cell::Cell<std::option::Option<rustpython_vm::PyObjectRef>>` cannot be shared between threads safely\nwithin `js_module::_js::AwaitPromise`, the trait `std::marker::Sync` is not implemented for `std::cell::Cell<std::option::Option<rustpython_vm::PyObjectRef>>`",
                related_information: Some(
                    [
                        DiagnosticRelatedInformation {
                            location: Location {
                                uri: Url {
                                    scheme: "file",
                                    cannot_be_a_base: false,
                                    username: "",
                                    password: None,
                                    host: None,
                                    port: None,
                                    path: "/Users/vsong/Downloads/fun/RustPython/wasm/lib/src/js_module.rs",
                                    query: None,
                                    fragment: None,
                                },
                                range: Range {
                                    start: Position {
                                        line: 558,
                                        character: 11,
                                    },
                                    end: Position {
                                        line: 558,
                                        character: 23,
                                    },
                                },
                            },
                            message: "required because it appears within the type `js_module::_js::AwaitPromise`",
                        },
                        DiagnosticRelatedInformation {
                            location: Location {
                                uri: Url {
                                    scheme: "file",
                                    cannot_be_a_base: false,
                                    username: "",
                                    password: None,
                                    host: None,
                                    port: None,
                                    path: "/Users/vsong/Downloads/fun/RustPython/vm/src/object/payload.rs",
                                    query: None,
                                    fragment: None,
                                },
                                range: Range {
                                    start: Position {
                                        line: 17,
                                        character: 39,
                                    },
                                    end: Position {
                                        line: 17,
                                        character: 60,
                                    },
                                },
                            },
                            message: "required by a bound in `rustpython_vm::PyPayload`",
                        },
                    ],
                ),
                tags: None,
                data: None,
            },
        ],
        only: Some(
            [
                CodeActionKind(
                    "quickfix",
                ),
            ],
        ),
    },
    work_done_progress_params: WorkDoneProgressParams {
        work_done_token: None,
    },
    partial_result_params: PartialResultParams {
        partial_result_token: None,
    },
}

thread 'Worker' panicked at 'already borrowed: BorrowMutError', crates/hir-ty/src/lower.rs:369:36
stack backtrace:
   0: _rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::result::unwrap_failed
   3: hir_ty::lower::TyLoweringContext::lower_ty_ext
   4: hir_ty::lower::TyLoweringContext::substs_from_path_segment
   5: hir_ty::lower::TyLoweringContext::lower_path_inner
   6: hir_ty::lower::TyLoweringContext::lower_partly_resolved_path
   7: hir_ty::lower::TyLoweringContext::lower_ty_ext
   8: hir_ty::lower::ty_query
   9: salsa::runtime::Runtime::execute_query_implementation
  10: salsa::derived::slot::Slot<Q,MP>::read_upgrade
  11: salsa::derived::slot::Slot<Q,MP>::read
  12: <salsa::derived::DerivedStorage<Q,MP> as salsa::plumbing::QueryStorageOps<Q>>::try_fetch
  13: salsa::QueryTable<Q>::get
  14: <DB as hir_ty::db::HirDatabase>::ty
  15: hir_ty::lower::TyLoweringContext::lower_path_inner
  16: hir_ty::lower::TyLoweringContext::lower_partly_resolved_path
  17: hir_ty::lower::TyLoweringContext::lower_ty_ext
  18: <alloc::vec::Vec<T> as alloc::vec::spec_from_iter::SpecFromIter<T,I>>::from_iter
  19: hir_ty::lower::callable_item_sig
  20: salsa::runtime::Runtime::execute_query_implementation
  21: salsa::derived::slot::Slot<Q,MP>::read_upgrade
  22: salsa::derived::slot::Slot<Q,MP>::read
  23: <salsa::derived::DerivedStorage<Q,MP> as salsa::plumbing::QueryStorageOps<Q>>::try_fetch
  24: salsa::QueryTable<Q>::get
  25: <DB as hir_ty::db::HirDatabase>::callable_item_signature
  26: hir_ty::infer::unify::InferenceTable::run_in_snapshot
  27: hir_ty::method_resolution::is_valid_candidate
  28: hir_ty::method_resolution::iterate_inherent_methods::impls_for_self_ty
  29: hir_ty::method_resolution::iterate_inherent_methods
  30: hir_ty::method_resolution::iterate_method_candidates_by_receiver
  31: hir_ty::method_resolution::iterate_method_candidates_dyn
  32: hir_ty::infer::expr::<impl hir_ty::infer::InferenceContext>::infer_expr_inner
  33: hir_ty::infer::expr::<impl hir_ty::infer::InferenceContext>::infer_expr
  34: hir_ty::infer::expr::<impl hir_ty::infer::InferenceContext>::infer_block
  35: hir_ty::infer::expr::<impl hir_ty::infer::InferenceContext>::infer_expr_inner
  36: hir_ty::infer::expr::<impl hir_ty::infer::InferenceContext>::infer_expr_coerce
  37: hir_ty::infer::infer_query
  38: salsa::runtime::Runtime::execute_query_implementation
  39: salsa::derived::slot::Slot<Q,MP>::read_upgrade
  40: salsa::derived::slot::Slot<Q,MP>::read
  41: <salsa::derived::DerivedStorage<Q,MP> as salsa::plumbing::QueryStorageOps<Q>>::try_fetch
  42: salsa::QueryTable<Q>::get
  43: <DB as hir_ty::db::HirDatabase>::infer_query
  44: hir_ty::db::infer_wait
  45: hir::DefWithBody::diagnostics
  46: hir::ModuleDef::diagnostics
  47: hir::Module::diagnostics
  48: ide_diagnostics::diagnostics
  49: std::panicking::try
  50: ide::Analysis::assists_with_fixes
  51: rust_analyzer::handlers::handle_code_action
  52: std::panicking::try
  53: <F as threadpool::FnBox>::call_box
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace. 

rust-analyzer version: 0.3.1186-standalone (e8e598f64 2022-08-28)

rustc version: rustc 1.63.0 (4b91a6ea7 2022-08-08)

relevant settings: For VSCode, "rust-analyzer.checkOnSave.command": "clippy" is set. The version of VSCode I'm currently using is 1.70.2.