src/tools/clippy/clippy_lints/src/casts/borrow_as_ptr.rs

   1 use clippy_utils::diagnostics::span_lint_and_sugg;
   2 use clippy_utils::is_no_std_crate;
   3 use clippy_utils::source::snippet_with_context;
   4 use rustc_errors::Applicability;
   5 use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, Ty, TyKind};
   6 use rustc_lint::LateContext;
   7
   8 use super::BORROW_AS_PTR;
   9
  10 pub(super) fn check<'tcx>(
  11     cx: &LateContext<'tcx>,
  12     expr: &'tcx Expr<'_>,
  13     cast_expr: &'tcx Expr<'_>,
  14     cast_to: &'tcx Ty<'_>,
  15 ) {
  16     if matches!(cast_to.kind, TyKind::Ptr(_))
  17         && let ExprKind::AddrOf(BorrowKind::Ref, mutability, e) = cast_expr.kind
  18     {
  19         let core_or_std = if is_no_std_crate(cx) { "core" } else { "std" };
  20         let macro_name = match mutability {
  21             Mutability::Not => "addr_of",
  22             Mutability::Mut => "addr_of_mut",
  23         };
  24         let mut app = Applicability::MachineApplicable;
  25         let snip = snippet_with_context(cx, e.span, cast_expr.span.ctxt(), "..", &mut app).0;
  26
  27         span_lint_and_sugg(
  28             cx,
  29             BORROW_AS_PTR,
  30             expr.span,
  31             "borrow as raw pointer",
  32             "try",
  33             format!("{core_or_std}::ptr::{macro_name}!({snip})"),
  34             Applicability::MachineApplicable,
  35         );
  36     }
  37 }