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|
use crate::{
context::{CheckLintNameResult, LintStore},
fluent_generated as fluent,
late::unerased_lint_store,
lints::{
DeprecatedLintName, IgnoredUnlessCrateSpecified, OverruledAttributeLint,
RenamedOrRemovedLint, RenamedOrRemovedLintSuggestion, UnknownLint, UnknownLintSuggestion,
},
};
use rustc_ast as ast;
use rustc_ast_pretty::pprust;
use rustc_data_structures::fx::FxHashMap;
use rustc_errors::{DecorateLint, DiagnosticBuilder, DiagnosticMessage, MultiSpan};
use rustc_hir as hir;
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::HirId;
use rustc_index::IndexVec;
use rustc_middle::hir::nested_filter;
use rustc_middle::lint::{
reveal_actual_level, struct_lint_level, LevelAndSource, LintExpectation, LintLevelSource,
ShallowLintLevelMap,
};
use rustc_middle::query::Providers;
use rustc_middle::ty::{RegisteredTools, TyCtxt};
use rustc_session::lint::builtin::{RENAMED_AND_REMOVED_LINTS, UNKNOWN_LINTS, UNUSED_ATTRIBUTES};
use rustc_session::lint::{
builtin::{self, FORBIDDEN_LINT_GROUPS, SINGLE_USE_LIFETIMES, UNFULFILLED_LINT_EXPECTATIONS},
Level, Lint, LintExpectationId, LintId,
};
use rustc_session::parse::{add_feature_diagnostics, feature_err};
use rustc_session::Session;
use rustc_span::symbol::{sym, Symbol};
use rustc_span::{Span, DUMMY_SP};
use crate::errors::{
MalformedAttribute, MalformedAttributeSub, OverruledAttribute, OverruledAttributeSub,
UnknownToolInScopedLint,
};
/// Collection of lint levels for the whole crate.
/// This is used by AST-based lints, which do not
/// wait until we have built HIR to be emitted.
#[derive(Debug)]
struct LintLevelSets {
/// Linked list of specifications.
list: IndexVec<LintStackIndex, LintSet>,
}
rustc_index::newtype_index! {
#[custom_encodable] // we don't need encoding
struct LintStackIndex {
const COMMAND_LINE = 0;
}
}
/// Specifications found at this position in the stack. This map only represents the lints
/// found for one set of attributes (like `shallow_lint_levels_on` does).
///
/// We store the level specifications as a linked list.
/// Each `LintSet` represents a set of attributes on the same AST node.
/// The `parent` forms a linked list that matches the AST tree.
/// This way, walking the linked list is equivalent to walking the AST bottom-up
/// to find the specifications for a given lint.
#[derive(Debug)]
struct LintSet {
// -A,-W,-D flags, a `Symbol` for the flag itself and `Level` for which
// flag.
specs: FxHashMap<LintId, LevelAndSource>,
parent: LintStackIndex,
}
impl LintLevelSets {
fn new() -> Self {
LintLevelSets { list: IndexVec::new() }
}
fn get_lint_level(
&self,
lint: &'static Lint,
idx: LintStackIndex,
aux: Option<&FxHashMap<LintId, LevelAndSource>>,
sess: &Session,
) -> LevelAndSource {
let lint = LintId::of(lint);
let (level, mut src) = self.raw_lint_id_level(lint, idx, aux);
let level = reveal_actual_level(level, &mut src, sess, lint, |id| {
self.raw_lint_id_level(id, idx, aux)
});
(level, src)
}
fn raw_lint_id_level(
&self,
id: LintId,
mut idx: LintStackIndex,
aux: Option<&FxHashMap<LintId, LevelAndSource>>,
) -> (Option<Level>, LintLevelSource) {
if let Some(specs) = aux {
if let Some(&(level, src)) = specs.get(&id) {
return (Some(level), src);
}
}
loop {
let LintSet { ref specs, parent } = self.list[idx];
if let Some(&(level, src)) = specs.get(&id) {
return (Some(level), src);
}
if idx == COMMAND_LINE {
return (None, LintLevelSource::Default);
}
idx = parent;
}
}
}
fn lint_expectations(tcx: TyCtxt<'_>, (): ()) -> Vec<(LintExpectationId, LintExpectation)> {
let store = unerased_lint_store(tcx);
let mut builder = LintLevelsBuilder {
sess: tcx.sess,
provider: QueryMapExpectationsWrapper {
tcx,
cur: hir::CRATE_HIR_ID,
specs: ShallowLintLevelMap::default(),
expectations: Vec::new(),
unstable_to_stable_ids: FxHashMap::default(),
empty: FxHashMap::default(),
},
warn_about_weird_lints: false,
store,
registered_tools: &tcx.registered_tools(()),
};
builder.add_command_line();
builder.add_id(hir::CRATE_HIR_ID);
tcx.hir().walk_toplevel_module(&mut builder);
tcx.sess.diagnostic().update_unstable_expectation_id(&builder.provider.unstable_to_stable_ids);
builder.provider.expectations
}
#[instrument(level = "trace", skip(tcx), ret)]
fn shallow_lint_levels_on(tcx: TyCtxt<'_>, owner: hir::OwnerId) -> ShallowLintLevelMap {
let store = unerased_lint_store(tcx);
let attrs = tcx.hir_attrs(owner);
let mut levels = LintLevelsBuilder {
sess: tcx.sess,
provider: LintLevelQueryMap {
tcx,
cur: owner.into(),
specs: ShallowLintLevelMap::default(),
empty: FxHashMap::default(),
attrs,
},
warn_about_weird_lints: false,
store,
registered_tools: &tcx.registered_tools(()),
};
if owner == hir::CRATE_OWNER_ID {
levels.add_command_line();
}
match attrs.map.range(..) {
// There is only something to do if there are attributes at all.
[] => {}
// Most of the time, there is only one attribute. Avoid fetching HIR in that case.
[(local_id, _)] => levels.add_id(HirId { owner, local_id: *local_id }),
// Otherwise, we need to visit the attributes in source code order, so we fetch HIR and do
// a standard visit.
// FIXME(#102522) Just iterate on attrs once that iteration order matches HIR's.
_ => match tcx.hir().owner(owner) {
hir::OwnerNode::Item(item) => levels.visit_item(item),
hir::OwnerNode::ForeignItem(item) => levels.visit_foreign_item(item),
hir::OwnerNode::TraitItem(item) => levels.visit_trait_item(item),
hir::OwnerNode::ImplItem(item) => levels.visit_impl_item(item),
hir::OwnerNode::Crate(mod_) => {
levels.add_id(hir::CRATE_HIR_ID);
levels.visit_mod(mod_, mod_.spans.inner_span, hir::CRATE_HIR_ID)
}
},
}
let specs = levels.provider.specs;
#[cfg(debug_assertions)]
for (_, v) in specs.specs.iter() {
debug_assert!(!v.is_empty());
}
specs
}
pub struct TopDown {
sets: LintLevelSets,
cur: LintStackIndex,
}
pub trait LintLevelsProvider {
fn current_specs(&self) -> &FxHashMap<LintId, LevelAndSource>;
fn insert(&mut self, id: LintId, lvl: LevelAndSource);
fn get_lint_level(&self, lint: &'static Lint, sess: &Session) -> LevelAndSource;
fn push_expectation(&mut self, _id: LintExpectationId, _expectation: LintExpectation) {}
}
impl LintLevelsProvider for TopDown {
fn current_specs(&self) -> &FxHashMap<LintId, LevelAndSource> {
&self.sets.list[self.cur].specs
}
fn insert(&mut self, id: LintId, lvl: LevelAndSource) {
self.sets.list[self.cur].specs.insert(id, lvl);
}
fn get_lint_level(&self, lint: &'static Lint, sess: &Session) -> LevelAndSource {
self.sets.get_lint_level(lint, self.cur, Some(self.current_specs()), sess)
}
}
struct LintLevelQueryMap<'tcx> {
tcx: TyCtxt<'tcx>,
cur: HirId,
specs: ShallowLintLevelMap,
/// Empty hash map to simplify code.
empty: FxHashMap<LintId, LevelAndSource>,
attrs: &'tcx hir::AttributeMap<'tcx>,
}
impl LintLevelsProvider for LintLevelQueryMap<'_> {
fn current_specs(&self) -> &FxHashMap<LintId, LevelAndSource> {
self.specs.specs.get(&self.cur.local_id).unwrap_or(&self.empty)
}
fn insert(&mut self, id: LintId, lvl: LevelAndSource) {
self.specs.specs.get_mut_or_insert_default(self.cur.local_id).insert(id, lvl);
}
fn get_lint_level(&self, lint: &'static Lint, _: &Session) -> LevelAndSource {
self.specs.lint_level_id_at_node(self.tcx, LintId::of(lint), self.cur)
}
}
struct QueryMapExpectationsWrapper<'tcx> {
tcx: TyCtxt<'tcx>,
/// HirId of the currently investigated element.
cur: HirId,
/// Level map for `cur`.
specs: ShallowLintLevelMap,
expectations: Vec<(LintExpectationId, LintExpectation)>,
unstable_to_stable_ids: FxHashMap<LintExpectationId, LintExpectationId>,
/// Empty hash map to simplify code.
empty: FxHashMap<LintId, LevelAndSource>,
}
impl LintLevelsProvider for QueryMapExpectationsWrapper<'_> {
fn current_specs(&self) -> &FxHashMap<LintId, LevelAndSource> {
self.specs.specs.get(&self.cur.local_id).unwrap_or(&self.empty)
}
fn insert(&mut self, id: LintId, lvl: LevelAndSource) {
self.specs.specs.get_mut_or_insert_default(self.cur.local_id).insert(id, lvl);
}
fn get_lint_level(&self, lint: &'static Lint, _: &Session) -> LevelAndSource {
// We cannot use `tcx.lint_level_at_node` because we want to know in which order the
// attributes have been inserted, in particular whether an `expect` follows a `forbid`.
self.specs.lint_level_id_at_node(self.tcx, LintId::of(lint), self.cur)
}
fn push_expectation(&mut self, id: LintExpectationId, expectation: LintExpectation) {
let LintExpectationId::Stable { attr_id: Some(attr_id), hir_id, attr_index, .. } = id else { bug!("unstable expectation id should already be mapped") };
let key = LintExpectationId::Unstable { attr_id, lint_index: None };
self.unstable_to_stable_ids.entry(key).or_insert(LintExpectationId::Stable {
hir_id,
attr_index,
lint_index: None,
attr_id: None,
});
self.expectations.push((id.normalize(), expectation));
}
}
impl<'tcx> LintLevelsBuilder<'_, LintLevelQueryMap<'tcx>> {
fn add_id(&mut self, hir_id: HirId) {
self.provider.cur = hir_id;
self.add(
self.provider.attrs.get(hir_id.local_id),
hir_id == hir::CRATE_HIR_ID,
Some(hir_id),
);
}
}
impl<'tcx> Visitor<'tcx> for LintLevelsBuilder<'_, LintLevelQueryMap<'tcx>> {
type NestedFilter = nested_filter::OnlyBodies;
fn nested_visit_map(&mut self) -> Self::Map {
self.provider.tcx.hir()
}
fn visit_param(&mut self, param: &'tcx hir::Param<'tcx>) {
self.add_id(param.hir_id);
intravisit::walk_param(self, param);
}
fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) {
self.add_id(it.hir_id());
intravisit::walk_item(self, it);
}
fn visit_foreign_item(&mut self, it: &'tcx hir::ForeignItem<'tcx>) {
self.add_id(it.hir_id());
intravisit::walk_foreign_item(self, it);
}
fn visit_stmt(&mut self, e: &'tcx hir::Stmt<'tcx>) {
// We will call `add_id` when we walk
// the `StmtKind`. The outer statement itself doesn't
// define the lint levels.
intravisit::walk_stmt(self, e);
}
fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) {
self.add_id(e.hir_id);
intravisit::walk_expr(self, e);
}
fn visit_field_def(&mut self, s: &'tcx hir::FieldDef<'tcx>) {
self.add_id(s.hir_id);
intravisit::walk_field_def(self, s);
}
fn visit_variant(&mut self, v: &'tcx hir::Variant<'tcx>) {
self.add_id(v.hir_id);
intravisit::walk_variant(self, v);
}
fn visit_local(&mut self, l: &'tcx hir::Local<'tcx>) {
self.add_id(l.hir_id);
intravisit::walk_local(self, l);
}
fn visit_arm(&mut self, a: &'tcx hir::Arm<'tcx>) {
self.add_id(a.hir_id);
intravisit::walk_arm(self, a);
}
fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
self.add_id(trait_item.hir_id());
intravisit::walk_trait_item(self, trait_item);
}
fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem<'tcx>) {
self.add_id(impl_item.hir_id());
intravisit::walk_impl_item(self, impl_item);
}
}
impl<'tcx> LintLevelsBuilder<'_, QueryMapExpectationsWrapper<'tcx>> {
fn add_id(&mut self, hir_id: HirId) {
// Change both the `HirId` and the associated specs.
self.provider.cur = hir_id;
self.provider.specs.specs.clear();
self.add(self.provider.tcx.hir().attrs(hir_id), hir_id == hir::CRATE_HIR_ID, Some(hir_id));
}
}
impl<'tcx> Visitor<'tcx> for LintLevelsBuilder<'_, QueryMapExpectationsWrapper<'tcx>> {
type NestedFilter = nested_filter::All;
fn nested_visit_map(&mut self) -> Self::Map {
self.provider.tcx.hir()
}
fn visit_param(&mut self, param: &'tcx hir::Param<'tcx>) {
self.add_id(param.hir_id);
intravisit::walk_param(self, param);
}
fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) {
self.add_id(it.hir_id());
intravisit::walk_item(self, it);
}
fn visit_foreign_item(&mut self, it: &'tcx hir::ForeignItem<'tcx>) {
self.add_id(it.hir_id());
intravisit::walk_foreign_item(self, it);
}
fn visit_stmt(&mut self, e: &'tcx hir::Stmt<'tcx>) {
// We will call `add_id` when we walk
// the `StmtKind`. The outer statement itself doesn't
// define the lint levels.
intravisit::walk_stmt(self, e);
}
fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) {
self.add_id(e.hir_id);
intravisit::walk_expr(self, e);
}
fn visit_field_def(&mut self, s: &'tcx hir::FieldDef<'tcx>) {
self.add_id(s.hir_id);
intravisit::walk_field_def(self, s);
}
fn visit_variant(&mut self, v: &'tcx hir::Variant<'tcx>) {
self.add_id(v.hir_id);
intravisit::walk_variant(self, v);
}
fn visit_local(&mut self, l: &'tcx hir::Local<'tcx>) {
self.add_id(l.hir_id);
intravisit::walk_local(self, l);
}
fn visit_arm(&mut self, a: &'tcx hir::Arm<'tcx>) {
self.add_id(a.hir_id);
intravisit::walk_arm(self, a);
}
fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
self.add_id(trait_item.hir_id());
intravisit::walk_trait_item(self, trait_item);
}
fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem<'tcx>) {
self.add_id(impl_item.hir_id());
intravisit::walk_impl_item(self, impl_item);
}
}
pub struct LintLevelsBuilder<'s, P> {
sess: &'s Session,
provider: P,
warn_about_weird_lints: bool,
store: &'s LintStore,
registered_tools: &'s RegisteredTools,
}
pub(crate) struct BuilderPush {
prev: LintStackIndex,
}
impl<'s> LintLevelsBuilder<'s, TopDown> {
pub(crate) fn new(
sess: &'s Session,
warn_about_weird_lints: bool,
store: &'s LintStore,
registered_tools: &'s RegisteredTools,
) -> Self {
let mut builder = LintLevelsBuilder {
sess,
provider: TopDown { sets: LintLevelSets::new(), cur: COMMAND_LINE },
warn_about_weird_lints,
store,
registered_tools,
};
builder.process_command_line();
assert_eq!(builder.provider.sets.list.len(), 1);
builder
}
fn process_command_line(&mut self) {
self.provider.cur = self
.provider
.sets
.list
.push(LintSet { specs: FxHashMap::default(), parent: COMMAND_LINE });
self.add_command_line();
}
/// Pushes a list of AST lint attributes onto this context.
///
/// This function will return a `BuilderPush` object which should be passed
/// to `pop` when this scope for the attributes provided is exited.
///
/// This function will perform a number of tasks:
///
/// * It'll validate all lint-related attributes in `attrs`
/// * It'll mark all lint-related attributes as used
/// * Lint levels will be updated based on the attributes provided
/// * Lint attributes are validated, e.g., a `#[forbid]` can't be switched to
/// `#[allow]`
///
/// Don't forget to call `pop`!
pub(crate) fn push(
&mut self,
attrs: &[ast::Attribute],
is_crate_node: bool,
source_hir_id: Option<HirId>,
) -> BuilderPush {
let prev = self.provider.cur;
self.provider.cur =
self.provider.sets.list.push(LintSet { specs: FxHashMap::default(), parent: prev });
self.add(attrs, is_crate_node, source_hir_id);
if self.provider.current_specs().is_empty() {
self.provider.sets.list.pop();
self.provider.cur = prev;
}
BuilderPush { prev }
}
/// Called after `push` when the scope of a set of attributes are exited.
pub(crate) fn pop(&mut self, push: BuilderPush) {
self.provider.cur = push.prev;
std::mem::forget(push);
}
}
#[cfg(debug_assertions)]
impl Drop for BuilderPush {
fn drop(&mut self) {
panic!("Found a `push` without a `pop`.");
}
}
impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
pub(crate) fn sess(&self) -> &Session {
self.sess
}
pub(crate) fn lint_store(&self) -> &LintStore {
self.store
}
fn current_specs(&self) -> &FxHashMap<LintId, LevelAndSource> {
self.provider.current_specs()
}
fn insert(&mut self, id: LintId, lvl: LevelAndSource) {
self.provider.insert(id, lvl)
}
fn add_command_line(&mut self) {
for &(ref lint_name, level) in &self.sess.opts.lint_opts {
self.store.check_lint_name_cmdline(self.sess, &lint_name, level, self.registered_tools);
let orig_level = level;
let lint_flag_val = Symbol::intern(lint_name);
let Ok(ids) = self.store.find_lints(&lint_name) else {
// errors handled in check_lint_name_cmdline above
continue
};
for id in ids {
// ForceWarn and Forbid cannot be overridden
if let Some((Level::ForceWarn(_) | Level::Forbid, _)) =
self.current_specs().get(&id)
{
continue;
}
if self.check_gated_lint(id, DUMMY_SP) {
let src = LintLevelSource::CommandLine(lint_flag_val, orig_level);
self.insert(id, (level, src));
}
}
}
}
/// Attempts to insert the `id` to `level_src` map entry. If unsuccessful
/// (e.g. if a forbid was already inserted on the same scope), then emits a
/// diagnostic with no change to `specs`.
fn insert_spec(&mut self, id: LintId, (mut level, src): LevelAndSource) {
let (old_level, old_src) = self.provider.get_lint_level(id.lint, &self.sess);
if let Level::Expect(id) = &mut level && let LintExpectationId::Stable { .. } = id {
*id = id.normalize();
}
// Setting to a non-forbid level is an error if the lint previously had
// a forbid level. Note that this is not necessarily true even with a
// `#[forbid(..)]` attribute present, as that is overridden by `--cap-lints`.
//
// This means that this only errors if we're truly lowering the lint
// level from forbid.
if level != Level::Forbid {
if let Level::Forbid = old_level {
// Backwards compatibility check:
//
// We used to not consider `forbid(lint_group)`
// as preventing `allow(lint)` for some lint `lint` in
// `lint_group`. For now, issue a future-compatibility
// warning for this case.
let id_name = id.lint.name_lower();
let fcw_warning = match old_src {
LintLevelSource::Default => false,
LintLevelSource::Node { name, .. } => self.store.is_lint_group(name),
LintLevelSource::CommandLine(symbol, _) => self.store.is_lint_group(symbol),
};
debug!(
"fcw_warning={:?}, specs.get(&id) = {:?}, old_src={:?}, id_name={:?}",
fcw_warning,
self.current_specs(),
old_src,
id_name
);
let sub = match old_src {
LintLevelSource::Default => {
OverruledAttributeSub::DefaultSource { id: id.to_string() }
}
LintLevelSource::Node { span, reason, .. } => {
OverruledAttributeSub::NodeSource { span, reason }
}
LintLevelSource::CommandLine(_, _) => OverruledAttributeSub::CommandLineSource,
};
if !fcw_warning {
self.sess.emit_err(OverruledAttribute {
span: src.span(),
overruled: src.span(),
lint_level: level.as_str(),
lint_source: src.name(),
sub,
});
} else {
self.emit_spanned_lint(
FORBIDDEN_LINT_GROUPS,
src.span().into(),
OverruledAttributeLint {
overruled: src.span(),
lint_level: level.as_str(),
lint_source: src.name(),
sub,
},
);
}
// Retain the forbid lint level, unless we are
// issuing a FCW. In the FCW case, we want to
// respect the new setting.
if !fcw_warning {
return;
}
}
}
// The lint `unfulfilled_lint_expectations` can't be expected, as it would suppress itself.
// Handling expectations of this lint would add additional complexity with little to no
// benefit. The expect level for this lint will therefore be ignored.
if let Level::Expect(_) = level && id == LintId::of(UNFULFILLED_LINT_EXPECTATIONS) {
return;
}
match (old_level, level) {
// If the new level is an expectation store it in `ForceWarn`
(Level::ForceWarn(_), Level::Expect(expectation_id)) => {
self.insert(id, (Level::ForceWarn(Some(expectation_id)), old_src))
}
// Keep `ForceWarn` level but drop the expectation
(Level::ForceWarn(_), _) => self.insert(id, (Level::ForceWarn(None), old_src)),
// Set the lint level as normal
_ => self.insert(id, (level, src)),
};
}
fn add(&mut self, attrs: &[ast::Attribute], is_crate_node: bool, source_hir_id: Option<HirId>) {
let sess = self.sess;
for (attr_index, attr) in attrs.iter().enumerate() {
if attr.has_name(sym::automatically_derived) {
self.insert(
LintId::of(SINGLE_USE_LIFETIMES),
(Level::Allow, LintLevelSource::Default),
);
continue;
}
let level = match Level::from_attr(attr) {
None => continue,
// This is the only lint level with a `LintExpectationId` that can be created from an attribute
Some(Level::Expect(unstable_id)) if let Some(hir_id) = source_hir_id => {
let LintExpectationId::Unstable { attr_id, lint_index } = unstable_id
else { bug!("stable id Level::from_attr") };
let stable_id = LintExpectationId::Stable {
hir_id,
attr_index: attr_index.try_into().unwrap(),
lint_index,
// we pass the previous unstable attr_id such that we can trace the ast id when building a map
// to go from unstable to stable id.
attr_id: Some(attr_id),
};
Level::Expect(stable_id)
}
Some(lvl) => lvl,
};
let Some(mut metas) = attr.meta_item_list() else {
continue
};
if metas.is_empty() {
// This emits the unused_attributes lint for `#[level()]`
continue;
}
// Before processing the lint names, look for a reason (RFC 2383)
// at the end.
let mut reason = None;
let tail_li = &metas[metas.len() - 1];
if let Some(item) = tail_li.meta_item() {
match item.kind {
ast::MetaItemKind::Word => {} // actual lint names handled later
ast::MetaItemKind::NameValue(ref name_value) => {
if item.path == sym::reason {
if let ast::LitKind::Str(rationale, _) = name_value.kind {
if !self.sess.features_untracked().lint_reasons {
feature_err(
&self.sess.parse_sess,
sym::lint_reasons,
item.span,
"lint reasons are experimental",
)
.emit();
}
reason = Some(rationale);
} else {
sess.emit_err(MalformedAttribute {
span: name_value.span,
sub: MalformedAttributeSub::ReasonMustBeStringLiteral(
name_value.span,
),
});
}
// found reason, reslice meta list to exclude it
metas.pop().unwrap();
} else {
sess.emit_err(MalformedAttribute {
span: item.span,
sub: MalformedAttributeSub::BadAttributeArgument(item.span),
});
}
}
ast::MetaItemKind::List(_) => {
sess.emit_err(MalformedAttribute {
span: item.span,
sub: MalformedAttributeSub::BadAttributeArgument(item.span),
});
}
}
}
for (lint_index, li) in metas.iter_mut().enumerate() {
let level = match level {
Level::Expect(mut id) => {
id.set_lint_index(Some(lint_index as u16));
Level::Expect(id)
}
level => level,
};
let sp = li.span();
let meta_item = match li {
ast::NestedMetaItem::MetaItem(meta_item) if meta_item.is_word() => meta_item,
_ => {
if let Some(item) = li.meta_item() {
if let ast::MetaItemKind::NameValue(_) = item.kind {
if item.path == sym::reason {
sess.emit_err(MalformedAttribute {
span: sp,
sub: MalformedAttributeSub::ReasonMustComeLast(sp),
});
continue;
}
}
}
sess.emit_err(MalformedAttribute {
span: sp,
sub: MalformedAttributeSub::BadAttributeArgument(sp),
});
continue;
}
};
let tool_ident = if meta_item.path.segments.len() > 1 {
Some(meta_item.path.segments.remove(0).ident)
} else {
None
};
let tool_name = tool_ident.map(|ident| ident.name);
let name = pprust::path_to_string(&meta_item.path);
let lint_result =
self.store.check_lint_name(&name, tool_name, self.registered_tools);
match &lint_result {
CheckLintNameResult::Ok(ids) => {
// This checks for instances where the user writes `#[expect(unfulfilled_lint_expectations)]`
// in that case we want to avoid overriding the lint level but instead add an expectation that
// can't be fulfilled. The lint message will include an explanation, that the
// `unfulfilled_lint_expectations` lint can't be expected.
if let Level::Expect(expect_id) = level {
// The `unfulfilled_lint_expectations` lint is not part of any lint groups. Therefore. we
// only need to check the slice if it contains a single lint.
let is_unfulfilled_lint_expectations = match ids {
[lint] => *lint == LintId::of(UNFULFILLED_LINT_EXPECTATIONS),
_ => false,
};
self.provider.push_expectation(
expect_id,
LintExpectation::new(
reason,
sp,
is_unfulfilled_lint_expectations,
tool_name,
),
);
}
let src = LintLevelSource::Node {
name: meta_item
.path
.segments
.last()
.expect("empty lint name")
.ident
.name,
span: sp,
reason,
};
for &id in *ids {
if self.check_gated_lint(id, attr.span) {
self.insert_spec(id, (level, src));
}
}
}
CheckLintNameResult::Tool(result) => {
match *result {
Ok(ids) => {
let complete_name =
&format!("{}::{}", tool_ident.unwrap().name, name);
let src = LintLevelSource::Node {
name: Symbol::intern(complete_name),
span: sp,
reason,
};
for &id in ids {
if self.check_gated_lint(id, attr.span) {
self.insert_spec(id, (level, src));
}
}
if let Level::Expect(expect_id) = level {
self.provider.push_expectation(
expect_id,
LintExpectation::new(reason, sp, false, tool_name),
);
}
}
Err((Some(ids), ref new_lint_name)) => {
let lint = builtin::RENAMED_AND_REMOVED_LINTS;
self.emit_spanned_lint(
lint,
sp.into(),
DeprecatedLintName {
name,
suggestion: sp,
replace: &new_lint_name,
},
);
let src = LintLevelSource::Node {
name: Symbol::intern(&new_lint_name),
span: sp,
reason,
};
for id in ids {
self.insert_spec(*id, (level, src));
}
if let Level::Expect(expect_id) = level {
self.provider.push_expectation(
expect_id,
LintExpectation::new(reason, sp, false, tool_name),
);
}
}
Err((None, _)) => {
// If Tool(Err(None, _)) is returned, then either the lint does not
// exist in the tool or the code was not compiled with the tool and
// therefore the lint was never added to the `LintStore`. To detect
// this is the responsibility of the lint tool.
}
}
}
&CheckLintNameResult::NoTool => {
sess.emit_err(UnknownToolInScopedLint {
span: tool_ident.map(|ident| ident.span),
tool_name: tool_name.unwrap(),
lint_name: pprust::path_to_string(&meta_item.path),
is_nightly_build: sess.is_nightly_build().then_some(()),
});
continue;
}
_ if !self.warn_about_weird_lints => {}
CheckLintNameResult::Warning(msg, renamed) => {
let suggestion =
renamed.as_ref().map(|replace| RenamedOrRemovedLintSuggestion {
suggestion: sp,
replace: replace.as_str(),
});
self.emit_spanned_lint(
RENAMED_AND_REMOVED_LINTS,
sp.into(),
RenamedOrRemovedLint { msg, suggestion },
);
}
CheckLintNameResult::NoLint(suggestion) => {
let name = if let Some(tool_ident) = tool_ident {
format!("{}::{}", tool_ident.name, name)
} else {
name.to_string()
};
let suggestion = suggestion
.map(|replace| UnknownLintSuggestion { suggestion: sp, replace });
self.emit_spanned_lint(
UNKNOWN_LINTS,
sp.into(),
UnknownLint { name, suggestion },
);
}
}
// If this lint was renamed, apply the new lint instead of ignoring the attribute.
// This happens outside of the match because the new lint should be applied even if
// we don't warn about the name change.
if let CheckLintNameResult::Warning(_, Some(new_name)) = lint_result {
// Ignore any errors or warnings that happen because the new name is inaccurate
// NOTE: `new_name` already includes the tool name, so we don't have to add it again.
if let CheckLintNameResult::Ok(ids) =
self.store.check_lint_name(&new_name, None, self.registered_tools)
{
let src = LintLevelSource::Node {
name: Symbol::intern(&new_name),
span: sp,
reason,
};
for &id in ids {
if self.check_gated_lint(id, attr.span) {
self.insert_spec(id, (level, src));
}
}
if let Level::Expect(expect_id) = level {
self.provider.push_expectation(
expect_id,
LintExpectation::new(reason, sp, false, tool_name),
);
}
} else {
panic!("renamed lint does not exist: {}", new_name);
}
}
}
}
if !is_crate_node {
for (id, &(level, ref src)) in self.current_specs().iter() {
if !id.lint.crate_level_only {
continue;
}
let LintLevelSource::Node { name: lint_attr_name, span: lint_attr_span, .. } = *src else {
continue
};
self.emit_spanned_lint(
UNUSED_ATTRIBUTES,
lint_attr_span.into(),
IgnoredUnlessCrateSpecified { level: level.as_str(), name: lint_attr_name },
);
// don't set a separate error for every lint in the group
break;
}
}
}
/// Checks if the lint is gated on a feature that is not enabled.
///
/// Returns `true` if the lint's feature is enabled.
// FIXME only emit this once for each attribute, instead of repeating it 4 times for
// pre-expansion lints, post-expansion lints, `shallow_lint_levels_on` and `lint_expectations`.
fn check_gated_lint(&self, lint_id: LintId, span: Span) -> bool {
if let Some(feature) = lint_id.lint.feature_gate {
if !self.sess.features_untracked().enabled(feature) {
let lint = builtin::UNKNOWN_LINTS;
let (level, src) = self.lint_level(builtin::UNKNOWN_LINTS);
struct_lint_level(
self.sess,
lint,
level,
src,
Some(span.into()),
fluent::lint_unknown_gated_lint,
|lint| {
lint.set_arg("name", lint_id.lint.name_lower());
lint.note(fluent::lint_note);
add_feature_diagnostics(lint, &self.sess.parse_sess, feature);
lint
},
);
return false;
}
}
true
}
/// Find the lint level for a lint.
pub fn lint_level(&self, lint: &'static Lint) -> LevelAndSource {
self.provider.get_lint_level(lint, self.sess)
}
/// Used to emit a lint-related diagnostic based on the current state of
/// this lint context.
///
/// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
///
/// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
#[rustc_lint_diagnostics]
pub(crate) fn struct_lint(
&self,
lint: &'static Lint,
span: Option<MultiSpan>,
msg: impl Into<DiagnosticMessage>,
decorate: impl for<'a, 'b> FnOnce(
&'b mut DiagnosticBuilder<'a, ()>,
) -> &'b mut DiagnosticBuilder<'a, ()>,
) {
let (level, src) = self.lint_level(lint);
struct_lint_level(self.sess, lint, level, src, span, msg, decorate)
}
pub fn emit_spanned_lint(
&self,
lint: &'static Lint,
span: MultiSpan,
decorate: impl for<'a> DecorateLint<'a, ()>,
) {
let (level, src) = self.lint_level(lint);
struct_lint_level(self.sess, lint, level, src, Some(span), decorate.msg(), |lint| {
decorate.decorate_lint(lint)
});
}
pub fn emit_lint(&self, lint: &'static Lint, decorate: impl for<'a> DecorateLint<'a, ()>) {
let (level, src) = self.lint_level(lint);
struct_lint_level(self.sess, lint, level, src, None, decorate.msg(), |lint| {
decorate.decorate_lint(lint)
});
}
}
pub(crate) fn provide(providers: &mut Providers) {
*providers = Providers { shallow_lint_levels_on, lint_expectations, ..*providers };
}
|