Remove LintExpectationId from Level variants

Author: oli-obk

compiler/rustc_lint/src/context.rs

@@ -17,13 +17,12 @@ use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
 use rustc_hir::{Pat, PatKind};
 use rustc_middle::bug;
+use rustc_middle::lint::LevelAndSource;
 use rustc_middle::middle::privacy::EffectiveVisibilities;
 use rustc_middle::ty::layout::{LayoutError, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::print::{PrintError, PrintTraitRefExt as _, Printer, with_no_trimmed_paths};
 use rustc_middle::ty::{self, GenericArg, RegisteredTools, Ty, TyCtxt, TypingEnv, TypingMode};
-use rustc_session::lint::{
-    FutureIncompatibleInfo, Level, Lint, LintBuffer, LintExpectationId, LintId,
-};
+use rustc_session::lint::{FutureIncompatibleInfo, Lint, LintBuffer, LintExpectationId, LintId};
 use rustc_session::{LintStoreMarker, Session};
 use rustc_span::edit_distance::find_best_match_for_names;
 use rustc_span::{Ident, Span, Symbol, sym};
@@ -573,7 +572,7 @@ pub trait LintContext {
     }
 
     /// This returns the lint level for the given lint at the current location.
-    fn get_lint_level(&self, lint: &'static Lint) -> Level;
+    fn get_lint_level(&self, lint: &'static Lint) -> LevelAndSource;
 
     /// This function can be used to manually fulfill an expectation. This can
     /// be used for lints which contain several spans, and should be suppressed,
@@ -642,8 +641,8 @@ impl<'tcx> LintContext for LateContext<'tcx> {
         }
     }
 
-    fn get_lint_level(&self, lint: &'static Lint) -> Level {
-        self.tcx.lint_level_at_node(lint, self.last_node_with_lint_attrs).level
+    fn get_lint_level(&self, lint: &'static Lint) -> LevelAndSource {
+        self.tcx.lint_level_at_node(lint, self.last_node_with_lint_attrs)
     }
 }
 
@@ -663,8 +662,8 @@ impl LintContext for EarlyContext<'_> {
         self.builder.opt_span_lint(lint, span.map(|s| s.into()), decorate)
     }
 
-    fn get_lint_level(&self, lint: &'static Lint) -> Level {
-        self.builder.lint_level(lint).level
+    fn get_lint_level(&self, lint: &'static Lint) -> LevelAndSource {
+        self.builder.lint_level(lint)
     }
 }
 

compiler/rustc_lint/src/levels.rs

@@ -84,28 +84,28 @@ impl LintLevelSets {
     ) -> 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| {
+        let (level, lint_id) = reveal_actual_level(level, &mut src, sess, lint, |id| {
             self.raw_lint_id_level(id, idx, aux)
         });
-        LevelAndSource { level, src }
+        LevelAndSource { level, lint_id, src }
     }
 
     fn raw_lint_id_level(
         &self,
         id: LintId,
         mut idx: LintStackIndex,
         aux: Option<&FxIndexMap<LintId, LevelAndSource>>,
-    ) -> (Option<Level>, LintLevelSource) {
+    ) -> (Option<(Level, Option<LintExpectationId>)>, LintLevelSource) {
         if let Some(specs) = aux
-            && let Some(&LevelAndSource { level, src }) = specs.get(&id)
+            && let Some(&LevelAndSource { level, lint_id, src }) = specs.get(&id)
         {
-            return (Some(level), src);
+            return (Some((level, lint_id)), src);
         }
 
         loop {
             let LintSet { ref specs, parent } = self.list[idx];
-            if let Some(&LevelAndSource { level, src }) = specs.get(&id) {
-                return (Some(level), src);
+            if let Some(&LevelAndSource { level, lint_id, src }) = specs.get(&id) {
+                return (Some((level, lint_id)), src);
             }
             if idx == COMMAND_LINE {
                 return (None, LintLevelSource::Default);
@@ -379,13 +379,7 @@ impl<'tcx> Visitor<'tcx> for LintLevelMaximum<'tcx> {
     fn visit_attribute(&mut self, attribute: &'tcx hir::Attribute) {
         if matches!(
             Level::from_attr(attribute),
-            Some(
-                Level::Warn
-                    | Level::Deny
-                    | Level::Forbid
-                    | Level::Expect(..)
-                    | Level::ForceWarn(..),
-            )
+            Some((Level::Warn | Level::Deny | Level::Forbid | Level::Expect | Level::ForceWarn, _))
         ) {
             let store = unerased_lint_store(self.tcx.sess);
             // Lint attributes are always a metalist inside a
@@ -528,9 +522,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
         for &(ref lint_name, level) in &self.sess.opts.lint_opts {
             // Checks the validity of lint names derived from the command line.
             let (tool_name, lint_name_only) = parse_lint_and_tool_name(lint_name);
-            if lint_name_only == crate::WARNINGS.name_lower()
-                && matches!(level, Level::ForceWarn(_))
-            {
+            if lint_name_only == crate::WARNINGS.name_lower() && matches!(level, Level::ForceWarn) {
                 self.sess
                     .dcx()
                     .emit_err(UnsupportedGroup { lint_group: crate::WARNINGS.name_lower() });
@@ -573,7 +565,6 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
                 _ => {}
             };
 
-            let orig_level = level;
             let lint_flag_val = Symbol::intern(lint_name);
 
             let Ok(ids) = self.store.find_lints(lint_name) else {
@@ -582,15 +573,15 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
             };
             for id in ids {
                 // ForceWarn and Forbid cannot be overridden
-                if let Some(LevelAndSource { level: Level::ForceWarn(_) | Level::Forbid, .. }) =
+                if let Some(LevelAndSource { level: Level::ForceWarn | Level::Forbid, .. }) =
                     self.current_specs().get(&id)
                 {
                     continue;
                 }
 
                 if self.check_gated_lint(id, DUMMY_SP, true) {
-                    let src = LintLevelSource::CommandLine(lint_flag_val, orig_level);
-                    self.insert(id, LevelAndSource { level, src });
+                    let src = LintLevelSource::CommandLine(lint_flag_val, level);
+                    self.insert(id, LevelAndSource { level, lint_id: None, src });
                 }
             }
         }
@@ -599,8 +590,8 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
     /// 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, LevelAndSource { level, src }: LevelAndSource) {
-        let LevelAndSource { level: old_level, src: old_src } =
+    fn insert_spec(&mut self, id: LintId, LevelAndSource { level, lint_id, src }: LevelAndSource) {
+        let LevelAndSource { level: old_level, src: old_src, .. } =
             self.provider.get_lint_level(id.lint, self.sess);
 
         // Setting to a non-forbid level is an error if the lint previously had
@@ -673,24 +664,24 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
         // 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
+        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(
+            (Level::ForceWarn, Level::Expect) => {
+                self.insert(id, LevelAndSource { level: Level::ForceWarn, lint_id, src: old_src })
+            }
+            // Keep `ForceWarn` level but drop the expectation
+            (Level::ForceWarn, _) => self.insert(
                 id,
-                LevelAndSource { level: Level::ForceWarn(Some(expectation_id)), src: old_src },
+                LevelAndSource { level: Level::ForceWarn, lint_id: None, src: old_src },
             ),
-            // Keep `ForceWarn` level but drop the expectation
-            (Level::ForceWarn(_), _) => {
-                self.insert(id, LevelAndSource { level: Level::ForceWarn(None), src: old_src })
-            }
             // Set the lint level as normal
-            _ => self.insert(id, LevelAndSource { level, src }),
+            _ => self.insert(id, LevelAndSource { level, lint_id, src }),
         };
     }
 
@@ -705,7 +696,11 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
             if attr.has_name(sym::automatically_derived) {
                 self.insert(
                     LintId::of(SINGLE_USE_LIFETIMES),
-                    LevelAndSource { level: Level::Allow, src: LintLevelSource::Default },
+                    LevelAndSource {
+                        level: Level::Allow,
+                        lint_id: None,
+                        src: LintLevelSource::Default,
+                    },
                 );
                 continue;
             }
@@ -718,16 +713,20 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
             {
                 self.insert(
                     LintId::of(MISSING_DOCS),
-                    LevelAndSource { level: Level::Allow, src: LintLevelSource::Default },
+                    LevelAndSource {
+                        level: Level::Allow,
+                        lint_id: None,
+                        src: LintLevelSource::Default,
+                    },
                 );
                 continue;
             }
 
-            let level = match Level::from_attr(attr) {
+            let (level, lint_id) = 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 => {
+                Some((Level::Expect, Some(unstable_id))) if let Some(hir_id) = source_hir_id => {
                     let LintExpectationId::Unstable { lint_index: None, attr_id: _ } = unstable_id
                     else {
                         bug!("stable id Level::from_attr")
@@ -739,9 +738,9 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
                         lint_index: None,
                     };
 
-                    Level::Expect(stable_id)
+                    (Level::Expect, Some(stable_id))
                 }
-                Some(lvl) => lvl,
+                Some((lvl, id)) => (lvl, id),
             };
 
             let Some(mut metas) = attr.meta_item_list() else { continue };
@@ -789,13 +788,10 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
             }
 
             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 mut lint_id = lint_id;
+                if let Some(id) = &mut lint_id {
+                    id.set_lint_index(Some(lint_index as u16));
+                }
 
                 let sp = li.span();
                 let meta_item = match li {
@@ -927,7 +923,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
                 let src = LintLevelSource::Node { name, span: sp, reason };
                 for &id in ids {
                     if self.check_gated_lint(id, sp, false) {
-                        self.insert_spec(id, LevelAndSource { level, src });
+                        self.insert_spec(id, LevelAndSource { level, lint_id, src });
                     }
                 }
 
@@ -936,7 +932,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
                 // 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 {
+                if let (Level::Expect, Some(expect_id)) = (level, lint_id) {
                     // 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.
@@ -958,7 +954,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
         }
 
         if self.lint_added_lints && !is_crate_node {
-            for (id, &LevelAndSource { level, ref src }) in self.current_specs().iter() {
+            for (id, &LevelAndSource { level, ref src, .. }) in self.current_specs().iter() {
                 if !id.lint.crate_level_only {
                     continue;
                 }

compiler/rustc_lint_defs/src/lib.rs

@@ -199,19 +199,19 @@ pub enum Level {
     ///
     /// See RFC 2383.
     ///
-    /// The [`LintExpectationId`] is used to later link a lint emission to the actual
+    /// Requires a [`LintExpectationId`] to later link a lint emission to the actual
     /// expectation. It can be ignored in most cases.
-    Expect(LintExpectationId),
+    Expect,
     /// 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
+    /// Requires a [`LintExpectationId`] to fulfill expectations marked via the
     /// `#[expect]` attribute, that will still be suppressed due to the level.
-    ForceWarn(Option<LintExpectationId>),
+    ForceWarn,
     /// The `deny` level will produce an error and stop further execution after the lint
     /// pass is complete.
     Deny,
@@ -225,9 +225,9 @@ impl Level {
     pub fn as_str(self) -> &'static str {
         match self {
             Level::Allow => "allow",
-            Level::Expect(_) => "expect",
+            Level::Expect => "expect",
             Level::Warn => "warn",
-            Level::ForceWarn(_) => "force-warn",
+            Level::ForceWarn => "force-warn",
             Level::Deny => "deny",
             Level::Forbid => "forbid",
         }
@@ -246,24 +246,30 @@ impl Level {
     }
 
     /// Converts an `Attribute` to a level.
-    pub fn from_attr(attr: &impl AttributeExt) -> Option<Self> {
+    pub fn from_attr(attr: &impl AttributeExt) -> Option<(Self, Option<LintExpectationId>)> {
         Self::from_symbol(attr.name_or_empty(), || Some(attr.id()))
     }
 
     /// Converts a `Symbol` to a level.
-    pub fn from_symbol(s: Symbol, id: impl FnOnce() -> Option<AttrId>) -> Option<Self> {
+    pub fn from_symbol(
+        s: Symbol,
+        id: impl FnOnce() -> Option<AttrId>,
+    ) -> Option<(Self, Option<LintExpectationId>)> {
         match s {
-            sym::allow => Some(Level::Allow),
+            sym::allow => Some((Level::Allow, None)),
             sym::expect => {
                 if let Some(attr_id) = id() {
-                    Some(Level::Expect(LintExpectationId::Unstable { attr_id, lint_index: None }))
+                    Some((
+                        Level::Expect,
+                        Some(LintExpectationId::Unstable { attr_id, lint_index: None }),
+                    ))
                 } else {
                     None
                 }
             }
-            sym::warn => Some(Level::Warn),
-            sym::deny => Some(Level::Deny),
-            sym::forbid => Some(Level::Forbid),
+            sym::warn => Some((Level::Warn, None)),
+            sym::deny => Some((Level::Deny, None)),
+            sym::forbid => Some((Level::Forbid, None)),
             _ => None,
         }
     }
@@ -274,26 +280,19 @@ impl Level {
             Level::Deny => "-D",
             Level::Forbid => "-F",
             Level::Allow => "-A",
-            Level::ForceWarn(_) => "--force-warn",
-            Level::Expect(_) => {
+            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::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.