38 lines
1.1 KiB
Rust
38 lines
1.1 KiB
Rust
use clippy_utils::diagnostics::span_lint_and_sugg;
|
|
use clippy_utils::ty::is_type_diagnostic_item;
|
|
use clippy_utils::{is_expr_untyped_identity_function, is_trait_method};
|
|
use rustc_errors::Applicability;
|
|
use rustc_hir as hir;
|
|
use rustc_lint::LateContext;
|
|
use rustc_span::{sym, Span};
|
|
|
|
use super::MAP_IDENTITY;
|
|
|
|
pub(super) fn check(
|
|
cx: &LateContext<'_>,
|
|
expr: &hir::Expr<'_>,
|
|
caller: &hir::Expr<'_>,
|
|
map_arg: &hir::Expr<'_>,
|
|
name: &str,
|
|
_map_span: Span,
|
|
) {
|
|
let caller_ty = cx.typeck_results().expr_ty(caller);
|
|
|
|
if (is_trait_method(cx, expr, sym::Iterator)
|
|
|| is_type_diagnostic_item(cx, caller_ty, sym::Result)
|
|
|| is_type_diagnostic_item(cx, caller_ty, sym::Option))
|
|
&& is_expr_untyped_identity_function(cx, map_arg)
|
|
&& let Some(sugg_span) = expr.span.trim_start(caller.span)
|
|
{
|
|
span_lint_and_sugg(
|
|
cx,
|
|
MAP_IDENTITY,
|
|
sugg_span,
|
|
"unnecessary map of the identity function",
|
|
&format!("remove the call to `{name}`"),
|
|
String::new(),
|
|
Applicability::MachineApplicable,
|
|
);
|
|
}
|
|
}
|