+#![feature(min_specialization)]
+
#[macro_use]
extern crate rustc_macros;
pub use self::Level::*;
use rustc_ast::node_id::{NodeId, NodeMap};
+use rustc_ast::{AttrId, Attribute};
use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
+use rustc_hir::HirId;
use rustc_serialize::json::Json;
use rustc_span::edition::Edition;
use rustc_span::{sym, symbol::Ident, MultiSpan, Span, Symbol};
($x:expr) => {
if $x != 1 { "s" } else { "" }
};
+ ("is", $x:expr) => {
+ if $x == 1 { "is" } else { "are" }
+ };
+ ("this", $x:expr) => {
+ if $x == 1 { "this" } else { "these" }
+ };
}
/// Indicates the confidence in the correctness of a suggestion.
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> },
+}
+
+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
+ }
+}
+
+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) } => {
+ 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) } => {
+ (*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)]
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,
ForceWarn,
+ /// 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,
}
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",
}
}
- /// Converts a lower-case string to a level.
+ /// 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),
- _ => None,
+ "expect" | _ => None,
}
}
/// Converts a symbol to a level.
- pub fn from_symbol(x: Symbol) -> Option<Level> {
- match x {
+ 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),
BreakWithLabelAndLoop(Span),
NamedAsmLabel(String),
UnicodeTextFlow(Span, String),
+ UnexpectedCfg((Symbol, Span), Option<(Symbol, Span)>),
+ DeprecatedWhereclauseLocation(Span, String),
}
/// Lints that are buffered up early on in the `Session` before the
projects / rustc.git / blobdiff