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#![feature(min_specialization)]
#![deny(rustc::untranslatable_diagnostic)]
#![deny(rustc::diagnostic_outside_of_impl)]
#[macro_use]
extern crate rustc_macros;
pub use self::Level::*;
use rustc_ast::node_id::NodeId;
use rustc_ast::{AttrId, Attribute};
use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
use rustc_error_messages::{DiagnosticMessage, MultiSpan};
use rustc_hir::HashStableContext;
use rustc_hir::HirId;
use rustc_span::edition::Edition;
use rustc_span::{sym, symbol::Ident, Span, Symbol};
use rustc_target::spec::abi::Abi;
use serde::{Deserialize, Serialize};
pub mod builtin;
#[macro_export]
macro_rules! pluralize {
// Pluralize based on count (e.g., apples)
($x:expr) => {
if $x == 1 { "" } else { "s" }
};
("has", $x:expr) => {
if $x == 1 { "has" } else { "have" }
};
("is", $x:expr) => {
if $x == 1 { "is" } else { "are" }
};
("was", $x:expr) => {
if $x == 1 { "was" } else { "were" }
};
("this", $x:expr) => {
if $x == 1 { "this" } else { "these" }
};
}
/// Indicates the confidence in the correctness of a suggestion.
///
/// All suggestions are marked with an `Applicability`. Tools use the applicability of a suggestion
/// to determine whether it should be automatically applied or if the user should be consulted
/// before applying the suggestion.
#[derive(Copy, Clone, Debug, Hash, Encodable, Decodable, Serialize, Deserialize)]
#[derive(PartialEq, Eq, PartialOrd, Ord)]
pub enum Applicability {
/// The suggestion is definitely what the user intended, or maintains the exact meaning of the code.
/// This suggestion should be automatically applied.
///
/// In case of multiple `MachineApplicable` suggestions (whether as part of
/// the same `multipart_suggestion` or not), all of them should be
/// automatically applied.
MachineApplicable,
/// The suggestion may be what the user intended, but it is uncertain. The suggestion should
/// result in valid Rust code if it is applied.
MaybeIncorrect,
/// The suggestion contains placeholders like `(...)` or `{ /* fields */ }`. The suggestion
/// cannot be applied automatically because it will not result in valid Rust code. The user
/// will need to fill in the placeholders.
HasPlaceholders,
/// The applicability of the suggestion is unknown.
Unspecified,
}
/// Each lint expectation has a `LintExpectationId` assigned by the `LintLevelsBuilder`.
/// Expected `Diagnostic`s get the lint level `Expect` which stores the `LintExpectationId`
/// to match it with the actual expectation later on.
///
/// The `LintExpectationId` has to be stable between compilations, as diagnostic
/// instances might be loaded from cache. Lint messages can be emitted during an
/// `EarlyLintPass` operating on the AST and during a `LateLintPass` traversing the
/// HIR tree. The AST doesn't have enough information to create a stable id. The
/// `LintExpectationId` will instead store the [`AttrId`] defining the expectation.
/// These `LintExpectationId` will be updated to use the stable [`HirId`] once the
/// AST has been lowered. The transformation is done by the `LintLevelsBuilder`
///
/// Each lint inside the `expect` attribute is tracked individually, the `lint_index`
/// identifies the lint inside the attribute and ensures that the IDs are unique.
///
/// The index values have a type of `u16` to reduce the size of the `LintExpectationId`.
/// It's reasonable to assume that no user will define 2^16 attributes on one node or
/// have that amount of lints listed. `u16` values should therefore suffice.
#[derive(Clone, Copy, PartialEq, PartialOrd, Eq, Ord, Debug, Hash, Encodable, Decodable)]
pub enum LintExpectationId {
/// Used for lints emitted during the `EarlyLintPass`. This id is not
/// hash stable and should not be cached.
Unstable { attr_id: AttrId, lint_index: Option<u16> },
/// The [`HirId`] that the lint expectation is attached to. This id is
/// stable and can be cached. The additional index ensures that nodes with
/// several expectations can correctly match diagnostics to the individual
/// expectation.
Stable { hir_id: HirId, attr_index: u16, lint_index: Option<u16>, attr_id: Option<AttrId> },
}
impl LintExpectationId {
pub fn is_stable(&self) -> bool {
match self {
LintExpectationId::Unstable { .. } => false,
LintExpectationId::Stable { .. } => true,
}
}
pub fn get_lint_index(&self) -> Option<u16> {
let (LintExpectationId::Unstable { lint_index, .. }
| LintExpectationId::Stable { lint_index, .. }) = self;
*lint_index
}
pub fn set_lint_index(&mut self, new_lint_index: Option<u16>) {
let (LintExpectationId::Unstable { ref mut lint_index, .. }
| LintExpectationId::Stable { ref mut lint_index, .. }) = self;
*lint_index = new_lint_index
}
/// Prepares the id for hashing. Removes references to the ast.
/// Should only be called when the id is stable.
pub fn normalize(self) -> Self {
match self {
Self::Stable { hir_id, attr_index, lint_index, .. } => {
Self::Stable { hir_id, attr_index, lint_index, attr_id: None }
}
Self::Unstable { .. } => {
unreachable!("`normalize` called when `ExpectationId` is unstable")
}
}
}
}
impl<HCX: rustc_hir::HashStableContext> HashStable<HCX> for LintExpectationId {
#[inline]
fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher) {
match self {
LintExpectationId::Stable {
hir_id,
attr_index,
lint_index: Some(lint_index),
attr_id: _,
} => {
hir_id.hash_stable(hcx, hasher);
attr_index.hash_stable(hcx, hasher);
lint_index.hash_stable(hcx, hasher);
}
_ => {
unreachable!(
"HashStable should only be called for filled and stable `LintExpectationId`"
)
}
}
}
}
impl<HCX: rustc_hir::HashStableContext> ToStableHashKey<HCX> for LintExpectationId {
type KeyType = (HirId, u16, u16);
#[inline]
fn to_stable_hash_key(&self, _: &HCX) -> Self::KeyType {
match self {
LintExpectationId::Stable {
hir_id,
attr_index,
lint_index: Some(lint_index),
attr_id: _,
} => (*hir_id, *attr_index, *lint_index),
_ => {
unreachable!("HashStable should only be called for a filled `LintExpectationId`")
}
}
}
}
/// Setting for how to handle a lint.
///
/// See: <https://doc.rust-lang.org/rustc/lints/levels.html>
#[derive(Clone, Copy, PartialEq, PartialOrd, Eq, Ord, Debug, Hash, HashStable_Generic)]
pub enum Level {
/// The `allow` level will not issue any message.
Allow,
/// The `expect` level will suppress the lint message but in turn produce a message
/// if the lint wasn't issued in the expected scope. `Expect` should not be used as
/// an initial level for a lint.
///
/// Note that this still means that the lint is enabled in this position and should
/// be emitted, this will in turn fulfill the expectation and suppress the lint.
///
/// See RFC 2383.
///
/// The [`LintExpectationId`] is used to later link a lint emission to the actual
/// expectation. It can be ignored in most cases.
Expect(LintExpectationId),
/// The `warn` level will produce a warning if the lint was violated, however the
/// compiler will continue with its execution.
Warn,
/// This lint level is a special case of [`Warn`], that can't be overridden. This is used
/// to ensure that a lint can't be suppressed. This lint level can currently only be set
/// via the console and is therefore session specific.
///
/// The [`LintExpectationId`] is intended to fulfill expectations marked via the
/// `#[expect]` attribute, that will still be suppressed due to the level.
ForceWarn(Option<LintExpectationId>),
/// The `deny` level will produce an error and stop further execution after the lint
/// pass is complete.
Deny,
/// `Forbid` is equivalent to the `deny` level but can't be overwritten like the previous
/// levels.
Forbid,
}
impl Level {
/// Converts a level to a lower-case string.
pub fn as_str(self) -> &'static str {
match self {
Level::Allow => "allow",
Level::Expect(_) => "expect",
Level::Warn => "warn",
Level::ForceWarn(_) => "force-warn",
Level::Deny => "deny",
Level::Forbid => "forbid",
}
}
/// Converts a lower-case string to a level. This will never construct the expect
/// level as that would require a [`LintExpectationId`]
pub fn from_str(x: &str) -> Option<Level> {
match x {
"allow" => Some(Level::Allow),
"warn" => Some(Level::Warn),
"deny" => Some(Level::Deny),
"forbid" => Some(Level::Forbid),
"expect" | _ => None,
}
}
/// Converts a symbol to a level.
pub fn from_attr(attr: &Attribute) -> Option<Level> {
match attr.name_or_empty() {
sym::allow => Some(Level::Allow),
sym::expect => Some(Level::Expect(LintExpectationId::Unstable {
attr_id: attr.id,
lint_index: None,
})),
sym::warn => Some(Level::Warn),
sym::deny => Some(Level::Deny),
sym::forbid => Some(Level::Forbid),
_ => None,
}
}
pub fn to_cmd_flag(self) -> &'static str {
match self {
Level::Warn => "-W",
Level::Deny => "-D",
Level::Forbid => "-F",
Level::Allow => "-A",
Level::ForceWarn(_) => "--force-warn",
Level::Expect(_) => {
unreachable!("the expect level does not have a commandline flag")
}
}
}
pub fn is_error(self) -> bool {
match self {
Level::Allow | Level::Expect(_) | Level::Warn | Level::ForceWarn(_) => false,
Level::Deny | Level::Forbid => true,
}
}
pub fn get_expectation_id(&self) -> Option<LintExpectationId> {
match self {
Level::Expect(id) | Level::ForceWarn(Some(id)) => Some(*id),
_ => None,
}
}
}
/// Specification of a single lint.
#[derive(Copy, Clone, Debug)]
pub struct Lint {
/// A string identifier for the lint.
///
/// This identifies the lint in attributes and in command-line arguments.
/// In those contexts it is always lowercase, but this field is compared
/// in a way which is case-insensitive for ASCII characters. This allows
/// `declare_lint!()` invocations to follow the convention of upper-case
/// statics without repeating the name.
///
/// The name is written with underscores, e.g., "unused_imports".
/// On the command line, underscores become dashes.
///
/// See <https://rustc-dev-guide.rust-lang.org/diagnostics.html#lint-naming>
/// for naming guidelines.
pub name: &'static str,
/// Default level for the lint.
///
/// See <https://rustc-dev-guide.rust-lang.org/diagnostics.html#diagnostic-levels>
/// for guidelines on choosing a default level.
pub default_level: Level,
/// Description of the lint or the issue it detects.
///
/// e.g., "imports that are never used"
pub desc: &'static str,
/// Starting at the given edition, default to the given lint level. If this is `None`, then use
/// `default_level`.
pub edition_lint_opts: Option<(Edition, Level)>,
/// `true` if this lint is reported even inside expansions of external macros.
pub report_in_external_macro: bool,
pub future_incompatible: Option<FutureIncompatibleInfo>,
pub is_plugin: bool,
/// `Some` if this lint is feature gated, otherwise `None`.
pub feature_gate: Option<Symbol>,
pub crate_level_only: bool,
}
/// Extra information for a future incompatibility lint.
#[derive(Copy, Clone, Debug)]
pub struct FutureIncompatibleInfo {
/// e.g., a URL for an issue/PR/RFC or error code
pub reference: &'static str,
/// The reason for the lint used by diagnostics to provide
/// the right help message
pub reason: FutureIncompatibilityReason,
/// Whether to explain the reason to the user.
///
/// Set to false for lints that already include a more detailed
/// explanation.
pub explain_reason: bool,
}
/// The reason for future incompatibility
#[derive(Copy, Clone, Debug)]
pub enum FutureIncompatibilityReason {
/// This will be an error in a future release for all editions
///
/// This will *not* show up in cargo's future breakage report.
/// The warning will hence only be seen in local crates, not in dependencies.
FutureReleaseErrorDontReportInDeps,
/// This will be an error in a future release, and
/// Cargo should create a report even for dependencies
///
/// This is the *only* reason that will make future incompatibility warnings show up in cargo's
/// reports. All other future incompatibility warnings are not visible when they occur in a
/// dependency.
FutureReleaseErrorReportInDeps,
/// Code that changes meaning in some way in a
/// future release.
FutureReleaseSemanticsChange,
/// Previously accepted code that will become an
/// error in the provided edition
EditionError(Edition),
/// Code that changes meaning in some way in
/// the provided edition
EditionSemanticsChange(Edition),
/// A custom reason.
Custom(&'static str),
}
impl FutureIncompatibilityReason {
pub fn edition(self) -> Option<Edition> {
match self {
Self::EditionError(e) => Some(e),
Self::EditionSemanticsChange(e) => Some(e),
_ => None,
}
}
}
impl FutureIncompatibleInfo {
pub const fn default_fields_for_macro() -> Self {
FutureIncompatibleInfo {
reference: "",
reason: FutureIncompatibilityReason::FutureReleaseErrorDontReportInDeps,
explain_reason: true,
}
}
}
impl Lint {
pub const fn default_fields_for_macro() -> Self {
Lint {
name: "",
default_level: Level::Forbid,
desc: "",
edition_lint_opts: None,
is_plugin: false,
report_in_external_macro: false,
future_incompatible: None,
feature_gate: None,
crate_level_only: false,
}
}
/// Gets the lint's name, with ASCII letters converted to lowercase.
pub fn name_lower(&self) -> String {
self.name.to_ascii_lowercase()
}
pub fn default_level(&self, edition: Edition) -> Level {
self.edition_lint_opts
.filter(|(e, _)| *e <= edition)
.map(|(_, l)| l)
.unwrap_or(self.default_level)
}
}
/// Identifies a lint known to the compiler.
#[derive(Clone, Copy, Debug)]
pub struct LintId {
// Identity is based on pointer equality of this field.
pub lint: &'static Lint,
}
impl PartialEq for LintId {
fn eq(&self, other: &LintId) -> bool {
std::ptr::eq(self.lint, other.lint)
}
}
impl Eq for LintId {}
impl std::hash::Hash for LintId {
fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
let ptr = self.lint as *const Lint;
ptr.hash(state);
}
}
impl LintId {
/// Gets the `LintId` for a `Lint`.
pub fn of(lint: &'static Lint) -> LintId {
LintId { lint }
}
pub fn lint_name_raw(&self) -> &'static str {
self.lint.name
}
/// Gets the name of the lint.
pub fn to_string(&self) -> String {
self.lint.name_lower()
}
}
impl<HCX> HashStable<HCX> for LintId {
#[inline]
fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher) {
self.lint_name_raw().hash_stable(hcx, hasher);
}
}
impl<HCX> ToStableHashKey<HCX> for LintId {
type KeyType = &'static str;
#[inline]
fn to_stable_hash_key(&self, _: &HCX) -> &'static str {
self.lint_name_raw()
}
}
#[derive(Debug)]
pub struct AmbiguityErrorDiag {
pub msg: String,
pub span: Span,
pub label_span: Span,
pub label_msg: String,
pub note_msg: String,
pub b1_span: Span,
pub b1_note_msg: String,
pub b1_help_msgs: Vec<String>,
pub b2_span: Span,
pub b2_note_msg: String,
pub b2_help_msgs: Vec<String>,
}
// This could be a closure, but then implementing derive trait
// becomes hacky (and it gets allocated).
#[derive(Debug)]
pub enum BuiltinLintDiagnostics {
Normal,
AbsPathWithModule(Span),
ProcMacroDeriveResolutionFallback(Span),
MacroExpandedMacroExportsAccessedByAbsolutePaths(Span),
ElidedLifetimesInPaths(usize, Span, bool, Span),
UnknownCrateTypes(Span, String, String),
UnusedImports(String, Vec<(Span, String)>, Option<Span>),
RedundantImport(Vec<(Span, bool)>, Ident),
DeprecatedMacro(Option<Symbol>, Span),
MissingAbi(Span, Abi),
UnusedDocComment(Span),
UnusedBuiltinAttribute {
attr_name: Symbol,
macro_name: String,
invoc_span: Span,
},
PatternsInFnsWithoutBody(Span, Ident),
LegacyDeriveHelpers(Span),
ProcMacroBackCompat(String),
OrPatternsBackCompat(Span, String),
ReservedPrefix(Span),
TrailingMacro(bool, Ident),
BreakWithLabelAndLoop(Span),
NamedAsmLabel(String),
UnicodeTextFlow(Span, String),
UnexpectedCfgName((Symbol, Span), Option<(Symbol, Span)>),
UnexpectedCfgValue((Symbol, Span), Option<(Symbol, Span)>),
DeprecatedWhereclauseLocation(Span, String),
SingleUseLifetime {
/// Span of the parameter which declares this lifetime.
param_span: Span,
/// Span of the code that should be removed when eliding this lifetime.
/// This span should include leading or trailing comma.
deletion_span: Option<Span>,
/// Span of the single use, or None if the lifetime is never used.
/// If true, the lifetime will be fully elided.
use_span: Option<(Span, bool)>,
},
NamedArgumentUsedPositionally {
/// Span where the named argument is used by position and will be replaced with the named
/// argument name
position_sp_to_replace: Option<Span>,
/// Span where the named argument is used by position and is used for lint messages
position_sp_for_msg: Option<Span>,
/// Span where the named argument's name is (so we know where to put the warning message)
named_arg_sp: Span,
/// String containing the named arguments name
named_arg_name: String,
/// Indicates if the named argument is used as a width/precision for formatting
is_formatting_arg: bool,
},
ByteSliceInPackedStructWithDerive,
UnusedExternCrate {
removal_span: Span,
},
ExternCrateNotIdiomatic {
vis_span: Span,
ident_span: Span,
},
AmbiguousGlobImports {
diag: AmbiguityErrorDiag,
},
AmbiguousGlobReexports {
/// The name for which collision(s) have occurred.
name: String,
/// The name space for which the collision(s) occurred in.
namespace: String,
/// Span where the name is first re-exported.
first_reexport_span: Span,
/// Span where the same name is also re-exported.
duplicate_reexport_span: Span,
},
HiddenGlobReexports {
/// The name of the local binding which shadows the glob re-export.
name: String,
/// The namespace for which the shadowing occurred in.
namespace: String,
/// The glob reexport that is shadowed by the local binding.
glob_reexport_span: Span,
/// The local binding that shadows the glob reexport.
private_item_span: Span,
},
UnusedQualifications {
/// The span of the unnecessarily-qualified path to remove.
removal_span: Span,
},
AssociatedConstElidedLifetime {
elided: bool,
span: Span,
},
}
/// Lints that are buffered up early on in the `Session` before the
/// `LintLevels` is calculated.
#[derive(Debug)]
pub struct BufferedEarlyLint {
/// The span of code that we are linting on.
pub span: MultiSpan,
/// The lint message.
pub msg: DiagnosticMessage,
/// The `NodeId` of the AST node that generated the lint.
pub node_id: NodeId,
/// A lint Id that can be passed to
/// `rustc_lint::early::EarlyContextAndPass::check_id`.
pub lint_id: LintId,
/// Customization of the `DiagnosticBuilder<'_>` for the lint.
pub diagnostic: BuiltinLintDiagnostics,
}
#[derive(Default, Debug)]
pub struct LintBuffer {
pub map: FxIndexMap<NodeId, Vec<BufferedEarlyLint>>,
}
impl LintBuffer {
pub fn add_early_lint(&mut self, early_lint: BufferedEarlyLint) {
let arr = self.map.entry(early_lint.node_id).or_default();
arr.push(early_lint);
}
pub fn add_lint(
&mut self,
lint: &'static Lint,
node_id: NodeId,
span: MultiSpan,
msg: impl Into<DiagnosticMessage>,
diagnostic: BuiltinLintDiagnostics,
) {
let lint_id = LintId::of(lint);
let msg = msg.into();
self.add_early_lint(BufferedEarlyLint { lint_id, node_id, span, msg, diagnostic });
}
pub fn take(&mut self, id: NodeId) -> Vec<BufferedEarlyLint> {
self.map.remove(&id).unwrap_or_default()
}
pub fn buffer_lint(
&mut self,
lint: &'static Lint,
id: NodeId,
sp: impl Into<MultiSpan>,
msg: impl Into<DiagnosticMessage>,
) {
self.add_lint(lint, id, sp.into(), msg, BuiltinLintDiagnostics::Normal)
}
pub fn buffer_lint_with_diagnostic(
&mut self,
lint: &'static Lint,
id: NodeId,
sp: impl Into<MultiSpan>,
msg: impl Into<DiagnosticMessage>,
diagnostic: BuiltinLintDiagnostics,
) {
self.add_lint(lint, id, sp.into(), msg, diagnostic)
}
}
pub type RegisteredTools = FxIndexSet<Ident>;
/// Declares a static item of type `&'static Lint`.
///
/// See <https://rustc-dev-guide.rust-lang.org/diagnostics.html> for
/// documentation and guidelines on writing lints.
///
/// The macro call should start with a doc comment explaining the lint
/// which will be embedded in the rustc user documentation book. It should
/// be written in markdown and have a format that looks like this:
///
/// ```rust,ignore (doc-example)
/// /// The `my_lint_name` lint detects [short explanation here].
/// ///
/// /// ### Example
/// ///
/// /// ```rust
/// /// [insert a concise example that triggers the lint]
/// /// ```
/// ///
/// /// {{produces}}
/// ///
/// /// ### Explanation
/// ///
/// /// This should be a detailed explanation of *why* the lint exists,
/// /// and also include suggestions on how the user should fix the problem.
/// /// Try to keep the text simple enough that a beginner can understand,
/// /// and include links to other documentation for terminology that a
/// /// beginner may not be familiar with. If this is "allow" by default,
/// /// it should explain why (are there false positives or other issues?). If
/// /// this is a future-incompatible lint, it should say so, with text that
/// /// looks roughly like this:
/// ///
/// /// This is a [future-incompatible] lint to transition this to a hard
/// /// error in the future. See [issue #xxxxx] for more details.
/// ///
/// /// [issue #xxxxx]: https://github.com/rust-lang/rust/issues/xxxxx
/// ```
///
/// The `{{produces}}` tag will be automatically replaced with the output from
/// the example by the build system. If the lint example is too complex to run
/// as a simple example (for example, it needs an extern crate), mark the code
/// block with `ignore` and manually replace the `{{produces}}` line with the
/// expected output in a `text` code block.
///
/// If this is a rustdoc-only lint, then only include a brief introduction
/// with a link with the text `[rustdoc book]` so that the validator knows
/// that this is for rustdoc only (see BROKEN_INTRA_DOC_LINKS as an example).
///
/// Commands to view and test the documentation:
///
/// * `./x.py doc --stage=1 src/doc/rustc --open`: Builds the rustc book and opens it.
/// * `./x.py test src/tools/lint-docs`: Validates that the lint docs have the
/// correct style, and that the code example actually emits the expected
/// lint.
///
/// If you have already built the compiler, and you want to make changes to
/// just the doc comments, then use the `--keep-stage=0` flag with the above
/// commands to avoid rebuilding the compiler.
#[macro_export]
macro_rules! declare_lint {
($(#[$attr:meta])* $vis: vis $NAME: ident, $Level: ident, $desc: expr) => (
$crate::declare_lint!(
$(#[$attr])* $vis $NAME, $Level, $desc,
);
);
($(#[$attr:meta])* $vis: vis $NAME: ident, $Level: ident, $desc: expr,
$(@feature_gate = $gate:expr;)?
$(@future_incompatible = FutureIncompatibleInfo {
reason: $reason:expr,
$($field:ident : $val:expr),* $(,)*
}; )?
$(@edition $lint_edition:ident => $edition_level:ident;)?
$($v:ident),*) => (
$(#[$attr])*
$vis static $NAME: &$crate::Lint = &$crate::Lint {
name: stringify!($NAME),
default_level: $crate::$Level,
desc: $desc,
is_plugin: false,
$($v: true,)*
$(feature_gate: Some($gate),)?
$(future_incompatible: Some($crate::FutureIncompatibleInfo {
reason: $reason,
$($field: $val,)*
..$crate::FutureIncompatibleInfo::default_fields_for_macro()
}),)?
$(edition_lint_opts: Some(($crate::Edition::$lint_edition, $crate::$edition_level)),)?
..$crate::Lint::default_fields_for_macro()
};
);
}
#[macro_export]
macro_rules! declare_tool_lint {
(
$(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level: ident, $desc: expr
$(, @feature_gate = $gate:expr;)?
) => (
$crate::declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, false $(, @feature_gate = $gate;)?}
);
(
$(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
report_in_external_macro: $rep:expr
$(, @feature_gate = $gate:expr;)?
) => (
$crate::declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, $rep $(, @feature_gate = $gate;)?}
);
(
$(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
$external:expr
$(, @feature_gate = $gate:expr;)?
) => (
$(#[$attr])*
$vis static $NAME: &$crate::Lint = &$crate::Lint {
name: &concat!(stringify!($tool), "::", stringify!($NAME)),
default_level: $crate::$Level,
desc: $desc,
edition_lint_opts: None,
report_in_external_macro: $external,
future_incompatible: None,
is_plugin: true,
$(feature_gate: Some($gate),)?
crate_level_only: false,
..$crate::Lint::default_fields_for_macro()
};
);
}
pub type LintVec = Vec<&'static Lint>;
pub trait LintPass {
fn name(&self) -> &'static str;
}
/// Implements `LintPass for $ty` with the given list of `Lint` statics.
#[macro_export]
macro_rules! impl_lint_pass {
($ty:ty => [$($lint:expr),* $(,)?]) => {
impl $crate::LintPass for $ty {
fn name(&self) -> &'static str { stringify!($ty) }
}
impl $ty {
pub fn get_lints() -> $crate::LintVec { vec![$($lint),*] }
}
};
}
/// Declares a type named `$name` which implements `LintPass`.
/// To the right of `=>` a comma separated list of `Lint` statics is given.
#[macro_export]
macro_rules! declare_lint_pass {
($(#[$m:meta])* $name:ident => [$($lint:expr),* $(,)?]) => {
$(#[$m])* #[derive(Copy, Clone)] pub struct $name;
$crate::impl_lint_pass!($name => [$($lint),*]);
};
}