refactor: improve code re-use in InstantSubtraction lint pass

This commit is contained in:
Nadir Fejzic 2022-11-07 21:34:24 +01:00
parent a566eb3765
commit 80e3553f29

View file

@ -1,6 +1,8 @@
use clippy_utils::{
diagnostics::{self, span_lint_and_sugg},
meets_msrv, msrvs, source, ty,
meets_msrv, msrvs, source,
sugg::Sugg,
ty,
};
use rustc_errors::Applicability;
use rustc_hir::{BinOpKind, Expr, ExprKind};
@ -78,45 +80,41 @@ impl_lint_pass!(InstantSubtraction => [MANUAL_INSTANT_ELAPSED, UNCHECKED_DURATIO
impl LateLintPass<'_> for InstantSubtraction {
fn check_expr(&mut self, cx: &LateContext<'_>, expr: &'_ Expr<'_>) {
if let ExprKind::Binary(Spanned {node: BinOpKind::Sub, ..}, lhs, rhs) = expr.kind
&& check_instant_now_call(cx, lhs)
&& let ty_resolved = cx.typeck_results().expr_ty(rhs)
&& let rustc_middle::ty::Adt(def, _) = ty_resolved.kind()
&& clippy_utils::match_def_path(cx, def.did(), &clippy_utils::paths::INSTANT)
&& let Some(sugg) = clippy_utils::sugg::Sugg::hir_opt(cx, rhs)
if let ExprKind::Binary(
Spanned {
node: BinOpKind::Sub, ..
},
lhs,
rhs,
) = expr.kind
{
span_lint_and_sugg(
cx,
MANUAL_INSTANT_ELAPSED,
expr.span,
"manual implementation of `Instant::elapsed`",
"try",
format!("{}.elapsed()", sugg.maybe_par()),
Applicability::MachineApplicable,
);
}
if expr.span.from_expansion() || !meets_msrv(self.msrv, msrvs::TRY_FROM) {
return;
}
if_chain! {
if let ExprKind::Binary(op, lhs, rhs) = expr.kind;
if is_instant_now_call(cx, lhs);
if let BinOpKind::Sub = op.node;
if is_an_instant(cx, rhs);
if let Some(sugg) = Sugg::hir_opt(cx, rhs);
then {
print_manual_instant_elapsed_sugg(cx, expr, sugg)
} else {
if_chain! {
if !expr.span.from_expansion();
if meets_msrv(self.msrv, msrvs::TRY_FROM);
// get types of left and right side
if is_an_instant(cx, lhs);
if is_a_duration(cx, rhs);
then {
print_lint_and_sugg(cx, lhs, rhs, expr)
print_unchecked_duration_subtraction_sugg(cx, lhs, rhs, expr)
}
}
}
}
}
}
}
fn check_instant_now_call(cx: &LateContext<'_>, expr_block: &'_ Expr<'_>) -> bool {
fn is_instant_now_call(cx: &LateContext<'_>, expr_block: &'_ Expr<'_>) -> bool {
if let ExprKind::Call(fn_expr, []) = expr_block.kind
&& let Some(fn_id) = clippy_utils::path_def_id(cx, fn_expr)
&& clippy_utils::match_def_path(cx, fn_id, &clippy_utils::paths::INSTANT_NOW)
@ -141,7 +139,24 @@ fn is_a_duration(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
ty::is_type_diagnostic_item(cx, expr_ty, sym::Duration)
}
fn print_lint_and_sugg(cx: &LateContext<'_>, left_expr: &Expr<'_>, right_expr: &Expr<'_>, expr: &Expr<'_>) {
fn print_manual_instant_elapsed_sugg(cx: &LateContext<'_>, expr: &Expr<'_>, sugg: Sugg<'_>) {
span_lint_and_sugg(
cx,
MANUAL_INSTANT_ELAPSED,
expr.span,
"manual implementation of `Instant::elapsed`",
"try",
format!("{}.elapsed()", sugg.maybe_par()),
Applicability::MachineApplicable,
);
}
fn print_unchecked_duration_subtraction_sugg(
cx: &LateContext<'_>,
left_expr: &Expr<'_>,
right_expr: &Expr<'_>,
expr: &Expr<'_>,
) {
let mut applicability = Applicability::MachineApplicable;
let left_expr =