Make BindInsteadOfMap a struct

Makes it codegen once instead of three times
This commit is contained in:
Alex Macleod 2024-07-23 20:57:35 +00:00
parent bd1224d8aa
commit 493498b65f
3 changed files with 68 additions and 49 deletions

View file

@ -8,7 +8,6 @@ reason = "this function does not add a link to our documentation, please use the
path = "rustc_lint::context::LintContext::span_lint"
reason = "this function does not add a link to our documentation, please use the `clippy_utils::diagnostics::span_lint*` functions instead"
[[disallowed-methods]]
path = "rustc_middle::ty::context::TyCtxt::node_span_lint"
reason = "this function does not add a link to our documentation, please use the `clippy_utils::diagnostics::span_lint_hir*` functions instead"

View file

@ -10,59 +10,80 @@ use rustc_hir::{LangItem, QPath};
use rustc_lint::LateContext;
use rustc_span::Span;
pub(crate) struct OptionAndThenSome;
impl BindInsteadOfMap for OptionAndThenSome {
const VARIANT_LANG_ITEM: LangItem = LangItem::OptionSome;
const BAD_METHOD_NAME: &'static str = "and_then";
const GOOD_METHOD_NAME: &'static str = "map";
pub(super) fn check_and_then_some(
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
recv: &hir::Expr<'_>,
arg: &hir::Expr<'_>,
) -> bool {
BindInsteadOfMap {
variant_lang_item: LangItem::OptionSome,
bad_method_name: "and_then",
good_method_name: "map",
}
.check(cx, expr, recv, arg)
}
pub(crate) struct ResultAndThenOk;
impl BindInsteadOfMap for ResultAndThenOk {
const VARIANT_LANG_ITEM: LangItem = LangItem::ResultOk;
const BAD_METHOD_NAME: &'static str = "and_then";
const GOOD_METHOD_NAME: &'static str = "map";
pub(super) fn check_and_then_ok(
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
recv: &hir::Expr<'_>,
arg: &hir::Expr<'_>,
) -> bool {
BindInsteadOfMap {
variant_lang_item: LangItem::ResultOk,
bad_method_name: "and_then",
good_method_name: "map",
}
.check(cx, expr, recv, arg)
}
pub(crate) struct ResultOrElseErrInfo;
impl BindInsteadOfMap for ResultOrElseErrInfo {
const VARIANT_LANG_ITEM: LangItem = LangItem::ResultErr;
const BAD_METHOD_NAME: &'static str = "or_else";
const GOOD_METHOD_NAME: &'static str = "map_err";
pub(super) fn check_or_else_err(
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
recv: &hir::Expr<'_>,
arg: &hir::Expr<'_>,
) -> bool {
BindInsteadOfMap {
variant_lang_item: LangItem::ResultErr,
bad_method_name: "or_else",
good_method_name: "map_err",
}
.check(cx, expr, recv, arg)
}
pub(crate) trait BindInsteadOfMap {
const VARIANT_LANG_ITEM: LangItem;
const BAD_METHOD_NAME: &'static str;
const GOOD_METHOD_NAME: &'static str;
struct BindInsteadOfMap {
variant_lang_item: LangItem,
bad_method_name: &'static str,
good_method_name: &'static str,
}
fn no_op_msg(cx: &LateContext<'_>) -> Option<String> {
let variant_id = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM)?;
impl BindInsteadOfMap {
fn no_op_msg(&self, cx: &LateContext<'_>) -> Option<String> {
let variant_id = cx.tcx.lang_items().get(self.variant_lang_item)?;
let item_id = cx.tcx.parent(variant_id);
Some(format!(
"using `{}.{}({})`, which is a no-op",
cx.tcx.item_name(item_id),
Self::BAD_METHOD_NAME,
self.bad_method_name,
cx.tcx.item_name(variant_id),
))
}
fn lint_msg(cx: &LateContext<'_>) -> Option<String> {
let variant_id = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM)?;
fn lint_msg(&self, cx: &LateContext<'_>) -> Option<String> {
let variant_id = cx.tcx.lang_items().get(self.variant_lang_item)?;
let item_id = cx.tcx.parent(variant_id);
Some(format!(
"using `{}.{}(|x| {}(y))`, which is more succinctly expressed as `{}(|x| y)`",
cx.tcx.item_name(item_id),
Self::BAD_METHOD_NAME,
self.bad_method_name,
cx.tcx.item_name(variant_id),
Self::GOOD_METHOD_NAME
self.good_method_name,
))
}
fn lint_closure_autofixable(
&self,
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
recv: &hir::Expr<'_>,
@ -71,9 +92,9 @@ pub(crate) trait BindInsteadOfMap {
) -> bool {
if let hir::ExprKind::Call(some_expr, [inner_expr]) = closure_expr.kind
&& let hir::ExprKind::Path(QPath::Resolved(_, path)) = some_expr.kind
&& Self::is_variant(cx, path.res)
&& self.is_variant(cx, path.res)
&& !contains_return(inner_expr)
&& let Some(msg) = Self::lint_msg(cx)
&& let Some(msg) = self.lint_msg(cx)
{
let mut app = Applicability::MachineApplicable;
let some_inner_snip = snippet_with_context(cx, inner_expr.span, closure_expr.span.ctxt(), "_", &mut app).0;
@ -82,7 +103,7 @@ pub(crate) trait BindInsteadOfMap {
let option_snip = snippet(cx, recv.span, "..");
let note = format!(
"{option_snip}.{}({closure_args_snip} {some_inner_snip})",
Self::GOOD_METHOD_NAME
self.good_method_name
);
span_lint_and_sugg(cx, BIND_INSTEAD_OF_MAP, expr.span, msg, "try", note, app);
true
@ -91,13 +112,13 @@ pub(crate) trait BindInsteadOfMap {
}
}
fn lint_closure(cx: &LateContext<'_>, expr: &hir::Expr<'_>, closure_expr: &hir::Expr<'_>) -> bool {
fn lint_closure(&self, cx: &LateContext<'_>, expr: &hir::Expr<'_>, closure_expr: &hir::Expr<'_>) -> bool {
let mut suggs = Vec::new();
let can_sugg: bool = find_all_ret_expressions(cx, closure_expr, |ret_expr| {
if !ret_expr.span.from_expansion()
&& let hir::ExprKind::Call(func_path, [arg]) = ret_expr.kind
&& let hir::ExprKind::Path(QPath::Resolved(_, path)) = func_path.kind
&& Self::is_variant(cx, path.res)
&& self.is_variant(cx, path.res)
&& !contains_return(arg)
{
suggs.push((ret_expr.span, arg.span.source_callsite()));
@ -108,7 +129,7 @@ pub(crate) trait BindInsteadOfMap {
});
let (span, msg) = if can_sugg
&& let hir::ExprKind::MethodCall(segment, ..) = expr.kind
&& let Some(msg) = Self::lint_msg(cx)
&& let Some(msg) = self.lint_msg(cx)
{
(segment.ident.span, msg)
} else {
@ -119,7 +140,7 @@ pub(crate) trait BindInsteadOfMap {
diag,
"try",
Applicability::MachineApplicable,
std::iter::once((span, Self::GOOD_METHOD_NAME.into())).chain(
std::iter::once((span, self.good_method_name.into())).chain(
suggs
.into_iter()
.map(|(span1, span2)| (span1, snippet(cx, span2, "_").into())),
@ -130,9 +151,9 @@ pub(crate) trait BindInsteadOfMap {
}
/// Lint use of `_.and_then(|x| Some(y))` for `Option`s
fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>, arg: &hir::Expr<'_>) -> bool {
fn check(&self, cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>, arg: &hir::Expr<'_>) -> bool {
if let Some(adt) = cx.typeck_results().expr_ty(recv).ty_adt_def()
&& let Some(vid) = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM)
&& let Some(vid) = cx.tcx.lang_items().get(self.variant_lang_item)
&& adt.did() == cx.tcx.parent(vid)
{
} else {
@ -144,15 +165,15 @@ pub(crate) trait BindInsteadOfMap {
let closure_body = cx.tcx.hir().body(body);
let closure_expr = peel_blocks(closure_body.value);
if Self::lint_closure_autofixable(cx, expr, recv, closure_expr, fn_decl_span) {
if self.lint_closure_autofixable(cx, expr, recv, closure_expr, fn_decl_span) {
true
} else {
Self::lint_closure(cx, expr, closure_expr)
self.lint_closure(cx, expr, closure_expr)
}
},
// `_.and_then(Some)` case, which is no-op.
hir::ExprKind::Path(QPath::Resolved(_, path)) if Self::is_variant(cx, path.res) => {
if let Some(msg) = Self::no_op_msg(cx) {
hir::ExprKind::Path(QPath::Resolved(_, path)) if self.is_variant(cx, path.res) => {
if let Some(msg) = self.no_op_msg(cx) {
span_lint_and_sugg(
cx,
BIND_INSTEAD_OF_MAP,
@ -169,9 +190,9 @@ pub(crate) trait BindInsteadOfMap {
}
}
fn is_variant(cx: &LateContext<'_>, res: Res) -> bool {
fn is_variant(&self, cx: &LateContext<'_>, res: Res) -> bool {
if let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Fn), id) = res {
if let Some(variant_id) = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM) {
if let Some(variant_id) = cx.tcx.lang_items().get(self.variant_lang_item) {
return cx.tcx.parent(id) == variant_id;
}
}

View file

@ -131,7 +131,6 @@ mod waker_clone_wake;
mod wrong_self_convention;
mod zst_offset;
use bind_instead_of_map::BindInsteadOfMap;
use clippy_config::msrvs::{self, Msrv};
use clippy_config::Conf;
use clippy_utils::consts::{constant, Constant};
@ -4506,8 +4505,8 @@ impl Methods {
}
},
("and_then", [arg]) => {
let biom_option_linted = bind_instead_of_map::OptionAndThenSome::check(cx, expr, recv, arg);
let biom_result_linted = bind_instead_of_map::ResultAndThenOk::check(cx, expr, recv, arg);
let biom_option_linted = bind_instead_of_map::check_and_then_some(cx, expr, recv, arg);
let biom_result_linted = bind_instead_of_map::check_and_then_ok(cx, expr, recv, arg);
if !biom_option_linted && !biom_result_linted {
unnecessary_lazy_eval::check(cx, expr, recv, arg, "and");
}
@ -4847,7 +4846,7 @@ impl Methods {
open_options::check(cx, expr, recv);
},
("or_else", [arg]) => {
if !bind_instead_of_map::ResultOrElseErrInfo::check(cx, expr, recv, arg) {
if !bind_instead_of_map::check_or_else_err(cx, expr, recv, arg) {
unnecessary_lazy_eval::check(cx, expr, recv, arg, "or");
}
},