Rollup merge of #88146 - BoxyUwU:tests-cec-incr-comp, r=oli-obk

Add tests for some `feature(const_evaluatable_checked)` incr comp issues

Closes #77650
Closes #79251

#79251 didn't seem to be ICEing anymore so added regression tests for that aswell

r? `@oli-obk`

src/test/incremental/const-generics/hash-tyvid-regression-1.rs

@@ -0,0 +1,15 @@
+// revisions: cfail
+#![feature(const_generics, const_evaluatable_checked)]
+#![allow(incomplete_features)]
+// regression test for #77650
+fn c<T, const N: std::num::NonZeroUsize>()
+where
+    [T; N.get()]: Sized,
+{
+    use std::convert::TryFrom;
+    <[T; N.get()]>::try_from(())
+    //~^ error: the trait bound
+    //~^^ error: mismatched types
+}
+
+fn main() {}

src/test/incremental/const-generics/hash-tyvid-regression-1.stderr

@@ -0,0 +1,35 @@
+error[E0277]: the trait bound `[T; _]: From<()>` is not satisfied
+  --> $DIR/hash-tyvid-regression-1.rs:9:5
+   |
+LL |     <[T; N.get()]>::try_from(())
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^ the trait `From<()>` is not implemented for `[T; _]`
+   |
+   = note: required because of the requirements on the impl of `Into<[T; _]>` for `()`
+   = note: required because of the requirements on the impl of `TryFrom<()>` for `[T; _]`
+note: required by `try_from`
+  --> $SRC_DIR/core/src/convert/mod.rs:LL:COL
+   |
+LL |     fn try_from(value: T) -> Result<Self, Self::Error>;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0308]: mismatched types
+  --> $DIR/hash-tyvid-regression-1.rs:9:5
+   |
+LL |     <[T; N.get()]>::try_from(())
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `()`, found enum `Result`
+   |
+   = note: expected unit type `()`
+                   found enum `Result<[T; _], Infallible>`
+help: consider using a semicolon here
+   |
+LL |     <[T; N.get()]>::try_from(());
+   |                                 +
+help: try adding a return type
+   |
+LL | -> Result<[T; _], Infallible> where
+   | +++++++++++++++++++++++++++++
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0277, E0308.
+For more information about an error, try `rustc --explain E0277`.

src/test/incremental/const-generics/hash-tyvid-regression-2.rs

@@ -0,0 +1,18 @@
+// revisions: cfail
+#![feature(const_generics, const_evaluatable_checked)]
+#![allow(incomplete_features)]
+// regression test for #77650
+struct C<T, const N: core::num::NonZeroUsize>([T; N.get()])
+where
+    [T; N.get()]: Sized;
+impl<'a, const N: core::num::NonZeroUsize, A, B: PartialEq<A>> PartialEq<&'a [A]> for C<B, N>
+where
+    [B; N.get()]: Sized,
+{
+    fn eq(&self, other: &&'a [A]) -> bool {
+        self.0 == other
+        //~^ error: can't compare
+    }
+}
+
+fn main() {}

src/test/incremental/const-generics/hash-tyvid-regression-2.stderr

@@ -0,0 +1,11 @@
+error[E0277]: can't compare `[B; _]` with `&&[A]`
+  --> $DIR/hash-tyvid-regression-2.rs:12:16
+   |
+LL |         self.0 == other
+   |                ^^ no implementation for `[B; _] == &&[A]`
+   |
+   = help: the trait `PartialEq<&&[A]>` is not implemented for `[B; _]`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.

src/test/incremental/const-generics/hash-tyvid-regression-3.rs

@@ -0,0 +1,26 @@
+// revisions: cfail
+#![feature(const_generics, const_evaluatable_checked)]
+#![allow(incomplete_features)]
+// regression test for #79251
+struct Node<const D: usize>
+where
+    SmallVec<{ D * 2 }>: ,
+{
+    keys: SmallVec<{ D * 2 }>,
+}
+
+impl<const D: usize> Node<D>
+where
+    SmallVec<{ D * 2 }>: ,
+{
+    fn new() -> Self {
+        let mut node = Node::new();
+        node.keys.some_function();
+        //~^ error: no method named
+        node
+    }
+}
+
+struct SmallVec<const D: usize> {}
+
+fn main() {}

src/test/incremental/const-generics/hash-tyvid-regression-3.stderr

@@ -0,0 +1,12 @@
+error[E0599]: no method named `some_function` found for struct `SmallVec` in the current scope
+  --> $DIR/hash-tyvid-regression-3.rs:17:19
+   |
+LL |         node.keys.some_function();
+   |                   ^^^^^^^^^^^^^ method not found in `SmallVec<{ D * 2 }>`
+...
+LL | struct SmallVec<const D: usize> {}
+   | ------------------------------- method `some_function` not found for this
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.

src/test/incremental/const-generics/hash-tyvid-regression-4.rs

@@ -0,0 +1,40 @@
+// revisions: cfail
+#![feature(const_generics, const_evaluatable_checked)]
+#![allow(incomplete_features)]
+// regression test for #79251
+#[derive(Debug)]
+struct Node<K, const D: usize>
+where
+    SmallVec<K, { D * 2 }>: ,
+{
+    keys: SmallVec<K, { D * 2 }>,
+}
+
+impl<K, const D: usize> Node<K, D>
+where
+    SmallVec<K, { D * 2 }>: ,
+{
+    fn new() -> Self {
+        panic!()
+    }
+
+    #[inline(never)]
+    fn split(&mut self, i: usize, k: K, right: bool) -> Node<K, D> {
+        let mut node = Node::new();
+        node.keys.push(k);
+        //~^ error: no method named
+        node
+    }
+}
+
+#[derive(Debug)]
+struct SmallVec<T, const D: usize> {
+    data: [T; D],
+}
+impl<T, const D: usize> SmallVec<T, D> {
+    fn new() -> Self {
+        panic!()
+    }
+}
+
+fn main() {}

src/test/incremental/const-generics/hash-tyvid-regression-4.stderr

@@ -0,0 +1,12 @@
+error[E0599]: no method named `push` found for struct `SmallVec` in the current scope
+  --> $DIR/hash-tyvid-regression-4.rs:23:19
+   |
+LL |         node.keys.push(k);
+   |                   ^^^^ method not found in `SmallVec<_, { D * 2 }>`
+...
+LL | struct SmallVec<T, const D: usize> {
+   | ---------------------------------- method `push` not found for this
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.