rust/clippy_lints/src/casts/borrow_as_ptr.rs
2025-02-28 18:15:11 +00:00

67 lines
2.5 KiB
Rust

use clippy_utils::diagnostics::span_lint_and_sugg;
use clippy_utils::msrvs::Msrv;
use clippy_utils::source::{snippet_with_applicability, snippet_with_context};
use clippy_utils::sugg::has_enclosing_paren;
use clippy_utils::{is_lint_allowed, msrvs, std_or_core};
use rustc_errors::Applicability;
use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, Ty, TyKind};
use rustc_lint::LateContext;
use rustc_middle::ty::adjustment::Adjust;
use rustc_span::BytePos;
use super::BORROW_AS_PTR;
pub(super) fn check<'tcx>(
cx: &LateContext<'tcx>,
expr: &'tcx Expr<'_>,
cast_expr: &'tcx Expr<'_>,
cast_to: &'tcx Ty<'_>,
msrv: Msrv,
) -> bool {
if matches!(cast_to.kind, TyKind::Ptr(_))
&& let ExprKind::AddrOf(BorrowKind::Ref, mutability, e) = cast_expr.kind
&& !is_lint_allowed(cx, BORROW_AS_PTR, expr.hir_id)
{
let mut app = Applicability::MachineApplicable;
let snip = snippet_with_context(cx, e.span, cast_expr.span.ctxt(), "..", &mut app).0;
// Fix #9884
if !e.is_place_expr(|base| {
cx.typeck_results()
.adjustments()
.get(base.hir_id)
.is_some_and(|x| x.iter().any(|adj| matches!(adj.kind, Adjust::Deref(_))))
}) {
return false;
}
let (suggestion, span) = if msrv.meets(cx, msrvs::RAW_REF_OP) {
let operator_kind = match mutability {
Mutability::Not => "const",
Mutability::Mut => "mut",
};
// Make sure that the span to be replaced doesn't include parentheses, that could break the
// suggestion.
let span = if has_enclosing_paren(snippet_with_applicability(cx, expr.span, "", &mut app)) {
expr.span
.with_lo(expr.span.lo() + BytePos(1))
.with_hi(expr.span.hi() - BytePos(1))
} else {
expr.span
};
(format!("&raw {operator_kind} {snip}"), span)
} else {
let Some(std_or_core) = std_or_core(cx) else {
return false;
};
let macro_name = match mutability {
Mutability::Not => "addr_of",
Mutability::Mut => "addr_of_mut",
};
(format!("{std_or_core}::ptr::{macro_name}!({snip})"), expr.span)
};
span_lint_and_sugg(cx, BORROW_AS_PTR, span, "borrow as raw pointer", "try", suggestion, app);
return true;
}
false
}