rust/clippy_lints/src/casts/as_underscore.rs

26 lines
898 B
Rust

use clippy_utils::diagnostics::span_lint_and_then;
use rustc_errors::Applicability;
use rustc_hir::{Expr, Ty, TyKind};
use rustc_lint::LateContext;
use rustc_middle::ty;
use super::AS_UNDERSCORE;
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, ty: &'tcx Ty<'_>) {
if matches!(ty.kind, TyKind::Infer) {
span_lint_and_then(cx, AS_UNDERSCORE, expr.span, "using `as _` conversion", |diag| {
let ty_resolved = cx.typeck_results().expr_ty(expr);
if let ty::Error(_) = ty_resolved.kind() {
diag.help("consider giving the type explicitly");
} else {
diag.span_suggestion(
ty.span,
"consider giving the type explicitly",
ty_resolved,
Applicability::MachineApplicable,
);
}
});
}
}