use crate::lints::{
BadOptAccessDiag, DefaultHashTypesDiag, DiagOutOfImpl, LintPassByHand, NonExistentDocKeyword,
QueryInstability, TyQualified, TykindDiag, TykindKind, UntranslatableDiag,
UntranslatableDiagnosticTrivial,
};
use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
use rustc_ast as ast;
use rustc_hir::def::Res;
use rustc_hir::{def_id::DefId, Expr, ExprKind, GenericArg, PatKind, Path, PathSegment, QPath};
use rustc_hir::{HirId, Impl, Item, ItemKind, Node, Pat, Ty, TyKind};
use rustc_middle::ty;
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::hygiene::{ExpnKind, MacroKind};
use rustc_span::symbol::{kw, sym, Symbol};
use rustc_span::Span;
declare_tool_lint! {
pub rustc::DEFAULT_HASH_TYPES,
Allow,
"forbid HashMap and HashSet and suggest the FxHash* variants",
report_in_external_macro: true
}
declare_lint_pass!(DefaultHashTypes => [DEFAULT_HASH_TYPES]);
impl LateLintPass<'_> for DefaultHashTypes {
fn check_path(&mut self, cx: &LateContext<'_>, path: &Path<'_>, hir_id: HirId) {
let Res::Def(rustc_hir::def::DefKind::Struct, def_id) = path.res else { return };
if matches!(cx.tcx.hir().get(hir_id), Node::Item(Item { kind: ItemKind::Use(..), .. })) {
return;
}
let preferred = match cx.tcx.get_diagnostic_name(def_id) {
Some(sym::HashMap) => "FxHashMap",
Some(sym::HashSet) => "FxHashSet",
_ => return,
};
cx.emit_spanned_lint(
DEFAULT_HASH_TYPES,
path.span,
DefaultHashTypesDiag { preferred, used: cx.tcx.item_name(def_id) },
);
}
}
fn typeck_results_of_method_fn<'tcx>(
cx: &LateContext<'tcx>,
expr: &Expr<'_>,
) -> Option<(Span, DefId, ty::GenericArgsRef<'tcx>)> {
match expr.kind {
ExprKind::MethodCall(segment, ..)
if let Some(def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id) =>
{
Some((segment.ident.span, def_id, cx.typeck_results().node_args(expr.hir_id)))
},
_ => {
match cx.typeck_results().node_type(expr.hir_id).kind() {
&ty::FnDef(def_id, args) => Some((expr.span, def_id, args)),
_ => None,
}
}
}
}
declare_tool_lint! {
pub rustc::POTENTIAL_QUERY_INSTABILITY,
Allow,
"require explicit opt-in when using potentially unstable methods or functions",
report_in_external_macro: true
}
declare_lint_pass!(QueryStability => [POTENTIAL_QUERY_INSTABILITY]);
impl LateLintPass<'_> for QueryStability {
fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
let Some((span, def_id, args)) = typeck_results_of_method_fn(cx, expr) else { return };
if let Ok(Some(instance)) = ty::Instance::resolve(cx.tcx, cx.param_env, def_id, args) {
let def_id = instance.def_id();
if cx.tcx.has_attr(def_id, sym::rustc_lint_query_instability) {
cx.emit_spanned_lint(
POTENTIAL_QUERY_INSTABILITY,
span,
QueryInstability { query: cx.tcx.item_name(def_id) },
);
}
}
}
}
declare_tool_lint! {
pub rustc::USAGE_OF_TY_TYKIND,
Allow,
"usage of `ty::TyKind` outside of the `ty::sty` module",
report_in_external_macro: true
}
declare_tool_lint! {
pub rustc::USAGE_OF_QUALIFIED_TY,
Allow,
"using `ty::{Ty,TyCtxt}` instead of importing it",
report_in_external_macro: true
}
declare_lint_pass!(TyTyKind => [
USAGE_OF_TY_TYKIND,
USAGE_OF_QUALIFIED_TY,
]);
impl<'tcx> LateLintPass<'tcx> for TyTyKind {
fn check_path(
&mut self,
cx: &LateContext<'tcx>,
path: &rustc_hir::Path<'tcx>,
_: rustc_hir::HirId,
) {
if let Some(segment) = path.segments.iter().nth_back(1)
&& lint_ty_kind_usage(cx, &segment.res)
{
let span = path.span.with_hi(
segment.args.map_or(segment.ident.span, |a| a.span_ext).hi()
);
cx.emit_spanned_lint(USAGE_OF_TY_TYKIND, path.span, TykindKind {
suggestion: span,
});
}
}
fn check_ty(&mut self, cx: &LateContext<'_>, ty: &'tcx Ty<'tcx>) {
match &ty.kind {
TyKind::Path(QPath::Resolved(_, path)) => {
if lint_ty_kind_usage(cx, &path.res) {
let hir = cx.tcx.hir();
let span = match hir.find_parent(ty.hir_id) {
Some(Node::Pat(Pat {
kind:
PatKind::Path(qpath)
| PatKind::TupleStruct(qpath, ..)
| PatKind::Struct(qpath, ..),
..
})) => {
if let QPath::TypeRelative(qpath_ty, ..) = qpath
&& qpath_ty.hir_id == ty.hir_id
{
Some(path.span)
} else {
None
}
}
Some(Node::Expr(Expr {
kind: ExprKind::Path(qpath),
..
})) => {
if let QPath::TypeRelative(qpath_ty, ..) = qpath
&& qpath_ty.hir_id == ty.hir_id
{
Some(path.span)
} else {
None
}
}
Some(Node::Expr(Expr {
kind: ExprKind::Struct(qpath, ..),
..
})) => {
if let QPath::TypeRelative(qpath_ty, ..) = qpath
&& qpath_ty.hir_id == ty.hir_id
{
Some(path.span)
} else {
None
}
}
_ => None
};
match span {
Some(span) => {
cx.emit_spanned_lint(USAGE_OF_TY_TYKIND, path.span, TykindKind {
suggestion: span,
});
},
None => cx.emit_spanned_lint(USAGE_OF_TY_TYKIND, path.span, TykindDiag),
}
} else if !ty.span.from_expansion() && path.segments.len() > 1 && let Some(ty) = is_ty_or_ty_ctxt(cx, &path) {
cx.emit_spanned_lint(USAGE_OF_QUALIFIED_TY, path.span, TyQualified {
ty,
suggestion: path.span,
});
}
}
_ => {}
}
}
}
fn lint_ty_kind_usage(cx: &LateContext<'_>, res: &Res) -> bool {
if let Some(did) = res.opt_def_id() {
cx.tcx.is_diagnostic_item(sym::TyKind, did) || cx.tcx.is_diagnostic_item(sym::IrTyKind, did)
} else {
false
}
}
fn is_ty_or_ty_ctxt(cx: &LateContext<'_>, path: &Path<'_>) -> Option<String> {
match &path.res {
Res::Def(_, def_id) => {
if let Some(name @ (sym::Ty | sym::TyCtxt)) = cx.tcx.get_diagnostic_name(*def_id) {
return Some(format!("{}{}", name, gen_args(path.segments.last().unwrap())));
}
}
Res::SelfTyAlias { alias_to: did, is_trait_impl: false, .. } => {
if let ty::Adt(adt, args) = cx.tcx.type_of(did).instantiate_identity().kind() {
if let Some(name @ (sym::Ty | sym::TyCtxt)) = cx.tcx.get_diagnostic_name(adt.did())
{
return Some(format!("{}<{}>", name, args[0]));
}
}
}
_ => (),
}
None
}
fn gen_args(segment: &PathSegment<'_>) -> String {
if let Some(args) = &segment.args {
let lifetimes = args
.args
.iter()
.filter_map(|arg| {
if let GenericArg::Lifetime(lt) = arg { Some(lt.ident.to_string()) } else { None }
})
.collect::<Vec<_>>();
if !lifetimes.is_empty() {
return format!("<{}>", lifetimes.join(", "));
}
}
String::new()
}
declare_tool_lint! {
pub rustc::LINT_PASS_IMPL_WITHOUT_MACRO,
Allow,
"`impl LintPass` without the `declare_lint_pass!` or `impl_lint_pass!` macros"
}
declare_lint_pass!(LintPassImpl => [LINT_PASS_IMPL_WITHOUT_MACRO]);
impl EarlyLintPass for LintPassImpl {
fn check_item(&mut self, cx: &EarlyContext<'_>, item: &ast::Item) {
if let ast::ItemKind::Impl(box ast::Impl { of_trait: Some(lint_pass), .. }) = &item.kind {
if let Some(last) = lint_pass.path.segments.last() {
if last.ident.name == sym::LintPass {
let expn_data = lint_pass.path.span.ctxt().outer_expn_data();
let call_site = expn_data.call_site;
if expn_data.kind != ExpnKind::Macro(MacroKind::Bang, sym::impl_lint_pass)
&& call_site.ctxt().outer_expn_data().kind
!= ExpnKind::Macro(MacroKind::Bang, sym::declare_lint_pass)
{
cx.emit_spanned_lint(
LINT_PASS_IMPL_WITHOUT_MACRO,
lint_pass.path.span,
LintPassByHand,
);
}
}
}
}
}
}
declare_tool_lint! {
pub rustc::EXISTING_DOC_KEYWORD,
Allow,
"Check that documented keywords in std and core actually exist",
report_in_external_macro: true
}
declare_lint_pass!(ExistingDocKeyword => [EXISTING_DOC_KEYWORD]);
fn is_doc_keyword(s: Symbol) -> bool {
s <= kw::Union
}
impl<'tcx> LateLintPass<'tcx> for ExistingDocKeyword {
fn check_item(&mut self, cx: &LateContext<'_>, item: &rustc_hir::Item<'_>) {
for attr in cx.tcx.hir().attrs(item.hir_id()) {
if !attr.has_name(sym::doc) {
continue;
}
if let Some(list) = attr.meta_item_list() {
for nested in list {
if nested.has_name(sym::keyword) {
let keyword = nested
.value_str()
.expect("#[doc(keyword = \"...\")] expected a value!");
if is_doc_keyword(keyword) {
return;
}
cx.emit_spanned_lint(
EXISTING_DOC_KEYWORD,
attr.span,
NonExistentDocKeyword { keyword },
);
}
}
}
}
}
}
declare_tool_lint! {
pub rustc::UNTRANSLATABLE_DIAGNOSTIC,
Allow,
"prevent creation of diagnostics which cannot be translated",
report_in_external_macro: true
}
declare_tool_lint! {
pub rustc::DIAGNOSTIC_OUTSIDE_OF_IMPL,
Allow,
"prevent creation of diagnostics outside of `IntoDiagnostic`/`AddToDiagnostic` impls",
report_in_external_macro: true
}
declare_tool_lint! {
pub rustc::UNTRANSLATABLE_DIAGNOSTIC_TRIVIAL,
Deny,
"prevent creation of diagnostics which cannot be translated, which use only static strings",
report_in_external_macro: true
}
declare_lint_pass!(Diagnostics => [ UNTRANSLATABLE_DIAGNOSTIC, DIAGNOSTIC_OUTSIDE_OF_IMPL, UNTRANSLATABLE_DIAGNOSTIC_TRIVIAL ]);
impl LateLintPass<'_> for Diagnostics {
fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
let Some((span, def_id, args)) = typeck_results_of_method_fn(cx, expr) else { return };
debug!(?span, ?def_id, ?args);
let has_attr = ty::Instance::resolve(cx.tcx, cx.param_env, def_id, args)
.ok()
.flatten()
.is_some_and(|inst| cx.tcx.has_attr(inst.def_id(), sym::rustc_lint_diagnostics));
if !has_attr {
return;
}
let mut found_parent_with_attr = false;
let mut found_impl = false;
for (hir_id, parent) in cx.tcx.hir().parent_iter(expr.hir_id) {
if let Some(owner_did) = hir_id.as_owner() {
found_parent_with_attr = found_parent_with_attr
|| cx.tcx.has_attr(owner_did, sym::rustc_lint_diagnostics);
}
debug!(?parent);
if let Node::Item(Item { kind: ItemKind::Impl(impl_), .. }) = parent &&
let Impl { of_trait: Some(of_trait), .. } = impl_ &&
let Some(def_id) = of_trait.trait_def_id() &&
let Some(name) = cx.tcx.get_diagnostic_name(def_id) &&
matches!(name, sym::IntoDiagnostic | sym::AddToDiagnostic | sym::DecorateLint)
{
found_impl = true;
break;
}
}
debug!(?found_impl);
if !found_parent_with_attr && !found_impl {
cx.emit_spanned_lint(DIAGNOSTIC_OUTSIDE_OF_IMPL, span, DiagOutOfImpl);
}
let mut found_diagnostic_message = false;
for ty in args.types() {
debug!(?ty);
if let Some(adt_def) = ty.ty_adt_def() &&
let Some(name) = cx.tcx.get_diagnostic_name(adt_def.did()) &&
matches!(name, sym::DiagnosticMessage | sym::SubdiagnosticMessage)
{
found_diagnostic_message = true;
break;
}
}
debug!(?found_diagnostic_message);
if !found_parent_with_attr && !found_diagnostic_message {
cx.emit_spanned_lint(UNTRANSLATABLE_DIAGNOSTIC, span, UntranslatableDiag);
}
}
}
impl EarlyLintPass for Diagnostics {
#[allow(unused_must_use)]
fn check_stmt(&mut self, cx: &EarlyContext<'_>, stmt: &ast::Stmt) {
let ast::StmtKind::Semi(expr) = &stmt.kind else {
return;
};
let ast::ExprKind::MethodCall(meth) = &expr.kind else {
return;
};
if meth.seg.ident.name != sym::emit || !meth.args.is_empty() {
return;
}
let mut segments = vec![];
let mut cur = &meth.receiver;
let fake = &[].into();
loop {
match &cur.kind {
ast::ExprKind::Call(func, args) => {
if let ast::ExprKind::Path(_, path) = &func.kind {
segments.push((path.segments.last().unwrap().ident.name, args))
}
break;
}
ast::ExprKind::MethodCall(method) => {
segments.push((method.seg.ident.name, &method.args));
cur = &method.receiver;
}
ast::ExprKind::MacCall(mac) => {
segments.push((mac.path.segments.last().unwrap().ident.name, fake));
break;
}
_ => {
break;
}
}
}
segments.reverse();
if segments.is_empty() {
return;
}
if segments[0].0.as_str() != "struct_span_err" {
return;
}
if !segments.iter().all(|(name, args)| {
let arg = match name.as_str() {
"struct_span_err" | "span_note" | "span_label" | "span_help" if args.len() == 2 => {
&args[1]
}
"note" | "help" if args.len() == 1 => &args[0],
_ => {
return false;
}
};
if let ast::ExprKind::Lit(lit) = arg.kind
&& let ast::token::LitKind::Str = lit.kind {
true
} else {
false
}
}) {
return;
}
cx.emit_spanned_lint(
UNTRANSLATABLE_DIAGNOSTIC_TRIVIAL,
stmt.span,
UntranslatableDiagnosticTrivial,
);
}
}
declare_tool_lint! {
pub rustc::BAD_OPT_ACCESS,
Deny,
"prevent using options by field access when there is a wrapper function",
report_in_external_macro: true
}
declare_lint_pass!(BadOptAccess => [ BAD_OPT_ACCESS ]);
impl LateLintPass<'_> for BadOptAccess {
fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
let ExprKind::Field(base, target) = expr.kind else { return };
let Some(adt_def) = cx.typeck_results().expr_ty(base).ty_adt_def() else { return };
if !cx.tcx.has_attr(adt_def.did(), sym::rustc_lint_opt_ty) {
return;
}
for field in adt_def.all_fields() {
if field.name == target.name &&
let Some(attr) = cx.tcx.get_attr(field.did, sym::rustc_lint_opt_deny_field_access) &&
let Some(items) = attr.meta_item_list() &&
let Some(item) = items.first() &&
let Some(lit) = item.lit() &&
let ast::LitKind::Str(val, _) = lit.kind
{
cx.emit_spanned_lint(BAD_OPT_ACCESS, expr.span, BadOptAccessDiag {
msg: val.as_str(),
});
}
}
}
}