fix: Normalize projections in evaluated const display and layout calculation

crates/hir-ty/src/consteval.rs

@@ -15,9 +15,10 @@ use stdx::never;
 use triomphe::Arc;
 
 use crate::{
-    db::HirDatabase, generics::Generics, infer::InferenceContext, lower::ParamLoweringMode,
-    mir::monomorphize_mir_body_bad, to_placeholder_idx, Const, ConstData, ConstScalar, ConstValue,
-    GenericArg, Interner, MemoryMap, Substitution, TraitEnvironment, Ty, TyBuilder,
+    db::HirDatabase, display::DisplayTarget, generics::Generics, infer::InferenceContext,
+    lower::ParamLoweringMode, mir::monomorphize_mir_body_bad, to_placeholder_idx, Const, ConstData,
+    ConstScalar, ConstValue, GenericArg, Interner, MemoryMap, Substitution, TraitEnvironment, Ty,
+    TyBuilder,
 };
 
 use super::mir::{interpret_mir, lower_to_mir, pad16, MirEvalError, MirLowerError};
@@ -62,11 +63,15 @@ impl ConstEvalError {
         f: &mut String,
         db: &dyn HirDatabase,
         span_formatter: impl Fn(span::FileId, span::TextRange) -> String,
-        edition: span::Edition,
+        display_target: DisplayTarget,
     ) -> std::result::Result<(), std::fmt::Error> {
         match self {
-            ConstEvalError::MirLowerError(e) => e.pretty_print(f, db, span_formatter, edition),
-            ConstEvalError::MirEvalError(e) => e.pretty_print(f, db, span_formatter, edition),
+            ConstEvalError::MirLowerError(e) => {
+                e.pretty_print(f, db, span_formatter, display_target)
+            }
+            ConstEvalError::MirEvalError(e) => {
+                e.pretty_print(f, db, span_formatter, display_target)
+            }
         }
     }
 }

crates/hir-ty/src/consteval/tests.rs

@@ -10,8 +10,8 @@ use test_fixture::WithFixture;
 use test_utils::skip_slow_tests;
 
 use crate::{
-    consteval::try_const_usize, db::HirDatabase, mir::pad16, test_db::TestDB, Const, ConstScalar,
-    Interner, MemoryMap,
+    consteval::try_const_usize, db::HirDatabase, display::DisplayTarget, mir::pad16,
+    test_db::TestDB, Const, ConstScalar, Interner, MemoryMap,
 };
 
 use super::{
@@ -101,11 +101,17 @@ fn check_answer(
 fn pretty_print_err(e: ConstEvalError, db: TestDB) -> String {
     let mut err = String::new();
     let span_formatter = |file, range| format!("{file:?} {range:?}");
-    let edition =
-        db.crate_graph()[*db.crate_graph().crates_in_topological_order().last().unwrap()].edition;
+    let display_target = DisplayTarget::from_crate(
+        &db,
+        *db.crate_graph().crates_in_topological_order().last().unwrap(),
+    );
     match e {
-        ConstEvalError::MirLowerError(e) => e.pretty_print(&mut err, &db, span_formatter, edition),
-        ConstEvalError::MirEvalError(e) => e.pretty_print(&mut err, &db, span_formatter, edition),
+        ConstEvalError::MirLowerError(e) => {
+            e.pretty_print(&mut err, &db, span_formatter, display_target)
+        }
+        ConstEvalError::MirEvalError(e) => {
+            e.pretty_print(&mut err, &db, span_formatter, display_target)
+        }
     }
     .unwrap();
     err

crates/hir-ty/src/diagnostics/expr.rs

@@ -16,7 +16,6 @@ use intern::sym;
 use itertools::Itertools;
 use rustc_hash::FxHashSet;
 use rustc_pattern_analysis::constructor::Constructor;
-use span::Edition;
 use syntax::{
     ast::{self, UnaryOp},
     AstNode,
@@ -31,7 +30,7 @@ use crate::{
         self,
         pat_analysis::{self, DeconstructedPat, MatchCheckCtx, WitnessPat},
     },
-    display::HirDisplay,
+    display::{DisplayTarget, HirDisplay},
     Adjust, InferenceResult, Interner, Ty, TyExt, TyKind,
 };
 
@@ -633,24 +632,24 @@ fn missing_match_arms<'p>(
     arms_is_empty: bool,
     krate: CrateId,
 ) -> String {
-    struct DisplayWitness<'a, 'p>(&'a WitnessPat<'p>, &'a MatchCheckCtx<'p>, Edition);
+    struct DisplayWitness<'a, 'p>(&'a WitnessPat<'p>, &'a MatchCheckCtx<'p>, DisplayTarget);
     impl fmt::Display for DisplayWitness<'_, '_> {
         fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-            let DisplayWitness(witness, cx, edition) = *self;
+            let DisplayWitness(witness, cx, display_target) = *self;
             let pat = cx.hoist_witness_pat(witness);
-            write!(f, "{}", pat.display(cx.db, edition))
+            write!(f, "{}", pat.display(cx.db, display_target))
         }
     }
 
-    let edition = cx.db.crate_graph()[krate].edition;
     let non_empty_enum = match scrut_ty.as_adt() {
         Some((AdtId::EnumId(e), _)) => !cx.db.enum_data(e).variants.is_empty(),
         _ => false,
     };
+    let display_target = DisplayTarget::from_crate(cx.db, krate);
     if arms_is_empty && !non_empty_enum {
-        format!("type `{}` is non-empty", scrut_ty.display(cx.db, edition))
+        format!("type `{}` is non-empty", scrut_ty.display(cx.db, display_target))
     } else {
-        let pat_display = |witness| DisplayWitness(witness, cx, edition);
+        let pat_display = |witness| DisplayWitness(witness, cx, display_target);
         const LIMIT: usize = 3;
         match &*witnesses {
             [witness] => format!("`{}` not covered", pat_display(witness)),