Rollup merge of rust-lang#113217 - ericmarkmartin:lower-type-relative-ctor-to-adt, r=cjgillot

resolve typerelative ctors to adt

Associated issue: rust-lang#110508

r? ``@spastorino``

Author: matthiaskrgr

compiler/rustc_mir_build/src/thir/cx/expr.rs

@@ -215,17 +215,18 @@ impl<'tcx> Cx<'tcx> {
             // so we wouldn't have to compute and store the actual value
 
             let hir::ExprKind::Path(ref qpath) = source.kind else {
-                return ExprKind::Cast { source: self.mirror_expr(source)};
+                return ExprKind::Cast { source: self.mirror_expr(source) };
             };
 
             let res = self.typeck_results().qpath_res(qpath, source.hir_id);
             let ty = self.typeck_results().node_type(source.hir_id);
             let ty::Adt(adt_def, substs) = ty.kind() else {
-                return ExprKind::Cast { source: self.mirror_expr(source)};
+                return ExprKind::Cast { source: self.mirror_expr(source) };
             };
 
-            let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Const), variant_ctor_id) = res else {
-                return ExprKind::Cast { source: self.mirror_expr(source)};
+            let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Const), variant_ctor_id) = res
+            else {
+                return ExprKind::Cast { source: self.mirror_expr(source) };
             };
 
             let idx = adt_def.variant_index_with_ctor_id(variant_ctor_id);
@@ -358,19 +359,35 @@ impl<'tcx> Cx<'tcx> {
                             });
                         }
                     }
-                    let adt_data =
-                        if let hir::ExprKind::Path(hir::QPath::Resolved(_, ref path)) = fun.kind {
-                            // Tuple-like ADTs are represented as ExprKind::Call. We convert them here.
-                            expr_ty.ty_adt_def().and_then(|adt_def| match path.res {
-                                Res::Def(DefKind::Ctor(_, CtorKind::Fn), ctor_id) => {
+
+                    // Tuple-like ADTs are represented as ExprKind::Call. We convert them here.
+                    let adt_data = if let hir::ExprKind::Path(ref qpath) = fun.kind
+                    && let Some(adt_def) = expr_ty.ty_adt_def() {
+                        match qpath {
+                            hir::QPath::Resolved(_, ref path) => {
+                                match path.res {
+                                    Res::Def(DefKind::Ctor(_, CtorKind::Fn), ctor_id) => {
+                                        Some((adt_def, adt_def.variant_index_with_ctor_id(ctor_id)))
+                                    }
+                                    Res::SelfCtor(..) => Some((adt_def, FIRST_VARIANT)),
+                                    _ => None,
+                                }
+                            }
+                            hir::QPath::TypeRelative(_ty, _) => {
+                                if let Some((DefKind::Ctor(_, CtorKind::Fn), ctor_id)) =
+                                    self.typeck_results().type_dependent_def(fun.hir_id)
+                                {
                                     Some((adt_def, adt_def.variant_index_with_ctor_id(ctor_id)))
+                                } else {
+                                    None
                                 }
-                                Res::SelfCtor(..) => Some((adt_def, FIRST_VARIANT)),
-                                _ => None,
-                            })
-                        } else {
-                            None
-                        };
+
+                            }
+                            _ => None,
+                        }
+                    } else {
+                        None
+                    };
                     if let Some((adt_def, index)) = adt_data {
                         let substs = self.typeck_results().node_substs(fun.hir_id);
                         let user_provided_types = self.typeck_results().user_provided_types();

tests/mir-opt/building/issue_110508.rs

@@ -0,0 +1,13 @@
+// EMIT_MIR issue_110508.{impl#0}-BAR.built.after.mir
+// EMIT_MIR issue_110508.{impl#0}-SELF_BAR.built.after.mir
+
+enum Foo {
+    Bar(()),
+}
+
+impl Foo {
+    const BAR: Foo = Foo::Bar(());
+    const SELF_BAR: Foo = Self::Bar(());
+}
+
+fn main() {}

tests/mir-opt/building/issue_110508.{impl#0}-BAR.built.after.mir

@@ -0,0 +1,14 @@
+// MIR for `<impl at $DIR/issue_110508.rs:8:1: 8:9>::BAR` after built
+
+const <impl at $DIR/issue_110508.rs:8:1: 8:9>::BAR: Foo = {
+    let mut _0: Foo;
+    let mut _1: ();
+
+    bb0: {
+        StorageLive(_1);
+        _1 = ();
+        _0 = Foo::Bar(move _1);
+        StorageDead(_1);
+        return;
+    }
+}

tests/mir-opt/building/issue_110508.{impl#0}-SELF_BAR.built.after.mir

@@ -0,0 +1,14 @@
+// MIR for `<impl at $DIR/issue_110508.rs:8:1: 8:9>::SELF_BAR` after built
+
+const <impl at $DIR/issue_110508.rs:8:1: 8:9>::SELF_BAR: Foo = {
+    let mut _0: Foo;
+    let mut _1: ();
+
+    bb0: {
+        StorageLive(_1);
+        _1 = ();
+        _0 = Foo::Bar(move _1);
+        StorageDead(_1);
+        return;
+    }
+}

tests/ui/nll/user-annotations/normalization-2.stderr

@@ -147,7 +147,7 @@ LL | fn test_variants<'a, 'b, 'c>() {
    |                      -- lifetime `'b` defined here
 ...
 LL |     <Ty<'b>>::Tuple();
-   |     ^^^^^^^^^^^^^^^ requires that `'b` must outlive `'static`
+   |     ^^^^^^^^^^^^^^^^^ requires that `'b` must outlive `'static`
 
 error: lifetime may not live long enough
   --> $DIR/normalization-2.rs:93:5

tests/ui/pattern/issue-110508.rs

@@ -0,0 +1,38 @@
+// run-pass
+
+#[derive(PartialEq, Eq)]
+pub enum Foo {
+    FooA(()),
+    FooB(Vec<()>),
+}
+
+impl Foo {
+    const A1: Foo = Foo::FooA(());
+    const A2: Foo = Self::FooA(());
+    const A3: Self = Foo::FooA(());
+    const A4: Self = Self::FooA(());
+}
+
+fn main() {
+    let foo = Foo::FooA(());
+
+    match foo {
+        Foo::A1 => {},
+        _ => {},
+    }
+
+    match foo {
+        Foo::A2 => {},
+        _ => {},
+    }
+
+    match foo {
+        Foo::A3 => {},
+        _ => {},
+    }
+
+    match foo {
+        Foo::A4 => {},
+        _ => {},
+    }
+}

tests/ui/thir-print/thir-flat-const-variant.rs

@@ -0,0 +1,18 @@
+// compile-flags: -Z unpretty=thir-flat
+// check-pass
+
+// Previously, the constants with `Self::Bar(())` would be `Call`s instead of
+// `Adt`s in THIR.
+
+pub enum Foo {
+    Bar(()),
+}
+
+impl Foo {
+    const BAR1: Foo = Foo::Bar(());
+    const BAR2: Foo = Self::Bar(());
+    const BAR3: Self = Foo::Bar(());
+    const BAR4: Self = Self::Bar(());
+}
+
+fn main() {}