add a few new solver normalization tests

tests/ui/associated-inherent-types/normalization-overflow.stderr → tests/ui/associated-inherent-types/normalization-overflow.current.stderr

@@ -1,5 +1,5 @@
 error: overflow evaluating associated type `T::This`
-  --> $DIR/normalization-overflow.rs:9:5
+  --> $DIR/normalization-overflow.rs:14:5
    |
 LL |     type This = Self::This;
    |     ^^^^^^^^^

tests/ui/associated-inherent-types/normalization-overflow.next.stderr

@@ -0,0 +1,9 @@
+error[E0271]: type mismatch resolving `T::This normalizes-to _`
+  --> $DIR/normalization-overflow.rs:14:5
+   |
+LL |     type This = Self::This;
+   |     ^^^^^^^^^ types differ
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0271`.

tests/ui/associated-inherent-types/normalization-overflow.rs

@@ -1,12 +1,19 @@
-#![feature(inherent_associated_types)]
+//@ revisions: current next
+//@ ignore-compare-mode-next-solver (explicit revisions)
+//@ [next] compile-flags: -Znext-solver
+
+#![feature(inherent_associated_types, rustc_attrs)]
 #![allow(incomplete_features)]
+#![rustc_no_implicit_bounds]
 
 // FIXME(fmease): I'd prefer to report a cycle error here instead of an overflow one.
 
 struct T;
 
 impl T {
-    type This = Self::This; //~ ERROR overflow evaluating associated type `T::This`
+    type This = Self::This;
+    //[current]~^ ERROR: overflow evaluating associated type `T::This`
+    //[next]~^^ ERROR: type mismatch resolving `T::This normalizes-to _`
 }
 
 fn main() {}

tests/ui/infinite/infinite-type-alias-mutual-recursion.feature_new.stderr

@@ -0,0 +1,21 @@
+error[E0271]: type mismatch resolving `X3 normalizes-to _`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:12:1
+   |
+LL | type X1 = X2;
+   | ^^^^^^^ types differ
+
+error[E0271]: type mismatch resolving `X1 normalizes-to _`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:16:1
+   |
+LL | type X2 = X3;
+   | ^^^^^^^ types differ
+
+error[E0271]: type mismatch resolving `X2 normalizes-to _`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:19:1
+   |
+LL | type X3 = X1;
+   | ^^^^^^^ types differ
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0271`.

tests/ui/infinite/infinite-type-alias-mutual-recursion.feature_old.stderr

@@ -0,0 +1,27 @@
+error[E0275]: overflow normalizing the type alias `X2`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:12:1
+   |
+LL | type X1 = X2;
+   | ^^^^^^^
+   |
+   = note: in case this is a recursive type alias, consider using a struct, enum, or union instead
+
+error[E0275]: overflow normalizing the type alias `X3`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:16:1
+   |
+LL | type X2 = X3;
+   | ^^^^^^^
+   |
+   = note: in case this is a recursive type alias, consider using a struct, enum, or union instead
+
+error[E0275]: overflow normalizing the type alias `X1`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:19:1
+   |
+LL | type X3 = X1;
+   | ^^^^^^^
+   |
+   = note: in case this is a recursive type alias, consider using a struct, enum, or union instead
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0275`.

tests/ui/infinite/infinite-type-alias-mutual-recursion.gated_new.stderr

@@ -0,0 +1,30 @@
+error[E0391]: cycle detected when expanding type alias `X1`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:12:11
+   |
+LL | type X1 = X2;
+   |           ^^
+   |
+note: ...which requires expanding type alias `X2`...
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:16:11
+   |
+LL | type X2 = X3;
+   |           ^^
+note: ...which requires expanding type alias `X3`...
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:19:11
+   |
+LL | type X3 = X1;
+   |           ^^
+   = note: ...which again requires expanding type alias `X1`, completing the cycle
+   = note: type aliases cannot be recursive
+   = help: consider using a struct, enum, or union instead to break the cycle
+   = help: see <https://doc.rust-lang.org/reference/types.html#recursive-types> for more information
+note: cycle used when checking that `X1` is well-formed
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:12:1
+   |
+LL | type X1 = X2;
+   | ^^^^^^^
+   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0391`.

tests/ui/infinite/infinite-type-alias-mutual-recursion.gated_old.stderr

@@ -0,0 +1,30 @@
+error[E0391]: cycle detected when expanding type alias `X1`
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:12:11
+   |
+LL | type X1 = X2;
+   |           ^^
+   |
+note: ...which requires expanding type alias `X2`...
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:16:11
+   |
+LL | type X2 = X3;
+   |           ^^
+note: ...which requires expanding type alias `X3`...
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:19:11
+   |
+LL | type X3 = X1;
+   |           ^^
+   = note: ...which again requires expanding type alias `X1`, completing the cycle
+   = note: type aliases cannot be recursive
+   = help: consider using a struct, enum, or union instead to break the cycle
+   = help: see <https://doc.rust-lang.org/reference/types.html#recursive-types> for more information
+note: cycle used when checking that `X1` is well-formed
+  --> $DIR/infinite-type-alias-mutual-recursion.rs:12:1
+   |
+LL | type X1 = X2;
+   | ^^^^^^^
+   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0391`.

tests/ui/infinite/infinite-type-alias-mutual-recursion.rs

@@ -1,14 +1,23 @@
-//@ revisions: feature gated
+//@ revisions: feature_old gated_old feature_new gated_new
 //@ ignore-parallel-frontend query cycle
-#![cfg_attr(feature, feature(lazy_type_alias))]
+//@ ignore-compare-mode-next-solver (explicit revisions)
+//@ [feature_new] compile-flags: -Znext-solver
+//@ [gated_new] compile-flags: -Znext-solver
+
+#![feature(rustc_attrs)]
+#![rustc_no_implicit_bounds]
+#![cfg_attr(any(feature_old, feature_new), feature(lazy_type_alias))]
 #![allow(incomplete_features)]
 
 type X1 = X2;
-//[gated]~^ ERROR cycle detected when expanding type alias `X1`
-//[feature]~^^ ERROR: overflow normalizing the type alias `X2`
+//[gated_old,gated_new]~^ ERROR cycle detected when expanding type alias `X1`
+//[feature_old]~^^ ERROR: overflow normalizing the type alias `X2`
+//[feature_new]~^^^ ERROR: type mismatch resolving `X3 normalizes-to _`
 type X2 = X3;
-//[feature]~^ ERROR: overflow normalizing the type alias `X3`
+//[feature_old]~^ ERROR: overflow normalizing the type alias `X3`
+//[feature_new]~^^ ERROR: type mismatch resolving `X1 normalizes-to _`
 type X3 = X1;
-//[feature]~^ ERROR: overflow normalizing the type alias `X1`
+//[feature_old]~^ ERROR: overflow normalizing the type alias `X1`
+//[feature_new]~^^ ERROR: type mismatch resolving `X2 normalizes-to _`
 
 fn main() {}

tests/ui/traits/normalize/normalize-diverging-alias-in-defaulted-type-parameter.rs

@@ -0,0 +1,25 @@
+// Ensure that defaulted type parameters whose default contains diverging aliases are properly
+// caught with both solvers. This is currently not the case, and this is tracked in issue
+// https://github.com/rust-lang/rust/issues/156271.
+// MCVE from https://github.com/rust-lang/trait-system-refactor-initiative/issues/139#issuecomment-2704576249.
+
+//@ revisions: current next
+//@ check-pass
+//@ known-bug: #156271
+//@ ignore-compare-mode-next-solver (explicit revisions)
+//@ [next] compile-flags: -Znext-solver
+
+#![feature(rustc_attrs)]
+#![rustc_no_implicit_bounds]
+
+trait Trait {
+    type Diverges<D: Trait>;
+}
+
+impl<T> Trait for T {
+    type Diverges<D: Trait> = D::Diverges<D>;
+}
+
+struct Bar<T = <u8 as Trait>::Diverges<u8>>(*mut T);
+
+fn main() {}

tests/ui/traits/normalize/normalize-diverging-alias-in-struct.current.stderr

@@ -0,0 +1,9 @@
+error[E0275]: overflow evaluating the requirement `<u8 as Trait>::Diverges<u8> == _`
+  --> $DIR/normalize-diverging-alias-in-struct.rs:21:12
+   |
+LL |     field: Box<<u8 as Trait>::Diverges<u8>>,
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0275`.

tests/ui/traits/normalize/normalize-diverging-alias-in-struct.next.stderr

@@ -0,0 +1,18 @@
+error[E0271]: type mismatch resolving `<u8 as Trait>::Diverges<u8> normalizes-to _`
+  --> $DIR/normalize-diverging-alias-in-struct.rs:21:12
+   |
+LL |     field: Box<<u8 as Trait>::Diverges<u8>>,
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ
+
+error[E0271]: type mismatch resolving `<u8 as Trait>::Diverges<u8> normalizes-to _`
+  --> $DIR/normalize-diverging-alias-in-struct.rs:21:12
+   |
+LL |     field: Box<<u8 as Trait>::Diverges<u8>>,
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ
+   |
+note: required by a bound in `Box`
+  --> $SRC_DIR/alloc/src/boxed.rs:LL:COL
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0271`.

tests/ui/traits/normalize/normalize-diverging-alias-in-struct.rs

@@ -0,0 +1,27 @@
+// Ensure that structs with fields whose types contain diverging aliases are properly caught with
+// both solvers.
+// MCVE from https://github.com/rust-lang/trait-system-refactor-initiative/issues/139#issuecomment-2703127026.
+
+//@ revisions: current next
+//@ ignore-compare-mode-next-solver (explicit revisions)
+//@ [next] compile-flags: -Znext-solver
+
+#![feature(rustc_attrs)]
+#![rustc_no_implicit_bounds]
+
+trait Trait {
+    type Diverges<D: Trait>;
+}
+
+impl<T> Trait for T {
+    type Diverges<D: Trait> = D::Diverges<D>;
+}
+
+struct Foo {
+    field: Box<<u8 as Trait>::Diverges<u8>>,
+    //[current]~^ ERROR: overflow evaluating the requirement `<u8 as Trait>::Diverges<u8> == _`
+    //[next]~^^ ERROR: type mismatch resolving `<u8 as Trait>::Diverges<u8> normalizes-to _`
+    //[next]~| ERROR: type mismatch resolving `<u8 as Trait>::Diverges<u8> normalizes-to _`
+}
+
+fn main() {}