1 pub use self::Level::*;
2 use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
3 use rustc_span::edition::Edition;
4 use rustc_span::{sym, symbol::Ident, MultiSpan, Span, Symbol};
5 use syntax::node_id::{NodeId, NodeMap};
9 /// Setting for how to handle a lint.
10 #[derive(Clone, Copy, PartialEq, PartialOrd, Eq, Ord, Debug, Hash)]
18 rustc_data_structures::impl_stable_hash_via_hash!(Level);
21 /// Converts a level to a lower-case string.
22 pub fn as_str(self) -> &'static str {
24 Level::Allow => "allow",
25 Level::Warn => "warn",
26 Level::Deny => "deny",
27 Level::Forbid => "forbid",
31 /// Converts a lower-case string to a level.
32 pub fn from_str(x: &str) -> Option<Level> {
34 "allow" => Some(Level::Allow),
35 "warn" => Some(Level::Warn),
36 "deny" => Some(Level::Deny),
37 "forbid" => Some(Level::Forbid),
42 /// Converts a symbol to a level.
43 pub fn from_symbol(x: Symbol) -> Option<Level> {
45 sym::allow => Some(Level::Allow),
46 sym::warn => Some(Level::Warn),
47 sym::deny => Some(Level::Deny),
48 sym::forbid => Some(Level::Forbid),
54 /// Specification of a single lint.
55 #[derive(Copy, Clone, Debug)]
57 /// A string identifier for the lint.
59 /// This identifies the lint in attributes and in command-line arguments.
60 /// In those contexts it is always lowercase, but this field is compared
61 /// in a way which is case-insensitive for ASCII characters. This allows
62 /// `declare_lint!()` invocations to follow the convention of upper-case
63 /// statics without repeating the name.
65 /// The name is written with underscores, e.g., "unused_imports".
66 /// On the command line, underscores become dashes.
67 pub name: &'static str,
69 /// Default level for the lint.
70 pub default_level: Level,
72 /// Description of the lint or the issue it detects.
74 /// e.g., "imports that are never used"
75 pub desc: &'static str,
77 /// Starting at the given edition, default to the given lint level. If this is `None`, then use
79 pub edition_lint_opts: Option<(Edition, Level)>,
81 /// `true` if this lint is reported even inside expansions of external macros.
82 pub report_in_external_macro: bool,
84 pub future_incompatible: Option<FutureIncompatibleInfo>,
89 /// Extra information for a future incompatibility lint.
90 #[derive(Copy, Clone, Debug)]
91 pub struct FutureIncompatibleInfo {
92 /// e.g., a URL for an issue/PR/RFC or error code
93 pub reference: &'static str,
94 /// If this is an edition fixing lint, the edition in which
95 /// this lint becomes obsolete
96 pub edition: Option<Edition>,
100 pub const fn default_fields_for_macro() -> Self {
103 default_level: Level::Forbid,
105 edition_lint_opts: None,
107 report_in_external_macro: false,
108 future_incompatible: None,
112 /// Gets the lint's name, with ASCII letters converted to lowercase.
113 pub fn name_lower(&self) -> String {
114 self.name.to_ascii_lowercase()
117 pub fn default_level(&self, edition: Edition) -> Level {
118 self.edition_lint_opts
119 .filter(|(e, _)| *e <= edition)
121 .unwrap_or(self.default_level)
125 /// Identifies a lint known to the compiler.
126 #[derive(Clone, Copy, Debug)]
128 // Identity is based on pointer equality of this field.
129 pub lint: &'static Lint,
132 impl PartialEq for LintId {
133 fn eq(&self, other: &LintId) -> bool {
134 std::ptr::eq(self.lint, other.lint)
138 impl Eq for LintId {}
140 impl std::hash::Hash for LintId {
141 fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
142 let ptr = self.lint as *const Lint;
148 /// Gets the `LintId` for a `Lint`.
149 pub fn of(lint: &'static Lint) -> LintId {
153 pub fn lint_name_raw(&self) -> &'static str {
157 /// Gets the name of the lint.
158 pub fn to_string(&self) -> String {
159 self.lint.name_lower()
163 impl<HCX> HashStable<HCX> for LintId {
165 fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher) {
166 self.lint_name_raw().hash_stable(hcx, hasher);
170 impl<HCX> ToStableHashKey<HCX> for LintId {
171 type KeyType = &'static str;
174 fn to_stable_hash_key(&self, _: &HCX) -> &'static str {
179 // This could be a closure, but then implementing derive trait
180 // becomes hacky (and it gets allocated).
182 pub enum BuiltinLintDiagnostics {
184 BareTraitObject(Span, /* is_global */ bool),
185 AbsPathWithModule(Span),
186 ProcMacroDeriveResolutionFallback(Span),
187 MacroExpandedMacroExportsAccessedByAbsolutePaths(Span),
188 ElidedLifetimesInPaths(usize, Span, bool, Span, String),
189 UnknownCrateTypes(Span, String, String),
190 UnusedImports(String, Vec<(Span, String)>),
191 RedundantImport(Vec<(Span, bool)>, Ident),
192 DeprecatedMacro(Option<Symbol>, Span),
193 UnusedDocComment(Span),
196 /// Lints that are buffered up early on in the `Session` before the
197 /// `LintLevels` is calculated. These are later passed to `librustc`.
199 pub struct BufferedEarlyLint {
200 /// The span of code that we are linting on.
203 /// The lint message.
206 /// The `NodeId` of the AST node that generated the lint.
209 /// A lint Id that can be passed to `rustc::lint::Lint::from_parser_lint_id`.
212 /// Customization of the `DiagnosticBuilder<'_>` for the lint.
213 pub diagnostic: BuiltinLintDiagnostics,
217 pub struct LintBuffer {
218 pub map: NodeMap<Vec<BufferedEarlyLint>>,
222 pub fn add_early_lint(&mut self, early_lint: BufferedEarlyLint) {
223 let arr = self.map.entry(early_lint.node_id).or_default();
224 if !arr.contains(&early_lint) {
225 arr.push(early_lint);
235 diagnostic: BuiltinLintDiagnostics,
237 let lint_id = LintId::of(lint);
238 let msg = msg.to_string();
239 self.add_early_lint(BufferedEarlyLint { lint_id, node_id, span, msg, diagnostic });
242 pub fn take(&mut self, id: NodeId) -> Vec<BufferedEarlyLint> {
243 self.map.remove(&id).unwrap_or_default()
250 sp: impl Into<MultiSpan>,
253 self.add_lint(lint, id, sp.into(), msg, BuiltinLintDiagnostics::Normal)
256 pub fn buffer_lint_with_diagnostic(
260 sp: impl Into<MultiSpan>,
262 diagnostic: BuiltinLintDiagnostics,
264 self.add_lint(lint, id, sp.into(), msg, diagnostic)
268 /// Declares a static item of type `&'static Lint`.
270 macro_rules! declare_lint {
271 ($vis: vis $NAME: ident, $Level: ident, $desc: expr) => (
272 $crate::declare_lint!(
273 $vis $NAME, $Level, $desc,
276 ($vis: vis $NAME: ident, $Level: ident, $desc: expr,
277 $(@future_incompatible = $fi:expr;)? $($v:ident),*) => (
278 $vis static $NAME: &$crate::lint::Lint = &$crate::lint::Lint {
279 name: stringify!($NAME),
280 default_level: $crate::lint::$Level,
282 edition_lint_opts: None,
285 $(future_incompatible: Some($fi),)*
286 ..$crate::lint::Lint::default_fields_for_macro()
289 ($vis: vis $NAME: ident, $Level: ident, $desc: expr,
290 $lint_edition: expr => $edition_level: ident
292 $vis static $NAME: &$crate::lint::Lint = &$crate::lint::Lint {
293 name: stringify!($NAME),
294 default_level: $crate::lint::$Level,
296 edition_lint_opts: Some(($lint_edition, $crate::lint::Level::$edition_level)),
297 report_in_external_macro: false,
304 macro_rules! declare_tool_lint {
306 $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level: ident, $desc: expr
308 $crate::declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, false}
311 $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
312 report_in_external_macro: $rep:expr
314 $crate::declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, $rep}
317 $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
321 $vis static $NAME: &$crate::lint::Lint = &$crate::lint::Lint {
322 name: &concat!(stringify!($tool), "::", stringify!($NAME)),
323 default_level: $crate::lint::$Level,
325 edition_lint_opts: None,
326 report_in_external_macro: $external,
327 future_incompatible: None,
333 /// Declares a static `LintArray` and return it as an expression.
335 macro_rules! lint_array {
336 ($( $lint:expr ),* ,) => { lint_array!( $($lint),* ) };
337 ($( $lint:expr ),*) => {{
342 pub type LintArray = Vec<&'static Lint>;
345 fn name(&self) -> &'static str;
348 /// Implements `LintPass for $name` with the given list of `Lint` statics.
350 macro_rules! impl_lint_pass {
351 ($name:ident => [$($lint:expr),* $(,)?]) => {
352 impl $crate::lint::LintPass for $name {
353 fn name(&self) -> &'static str { stringify!($name) }
356 pub fn get_lints() -> $crate::lint::LintArray { $crate::lint_array!($($lint),*) }
361 /// Declares a type named `$name` which implements `LintPass`.
362 /// To the right of `=>` a comma separated list of `Lint` statics is given.
364 macro_rules! declare_lint_pass {
365 ($(#[$m:meta])* $name:ident => [$($lint:expr),* $(,)?]) => {
366 $(#[$m])* #[derive(Copy, Clone)] pub struct $name;
367 $crate::impl_lint_pass!($name => [$($lint),*]);