check the types in `ty::Value` to value conversion

and remove `ty::Const::try_to_scalar` because it becomes redundant

3 files changed, 52 insertions, 6 deletions

diff --git a/tests/crashes/131102.rs b/tests/crashes/131102.rs
deleted file mode 100644
index 12b35f8d1b2..00000000000
--- a/tests/crashes/131102.rs
+++ /dev/null
@@ -1,4 +0,0 @@
-//@ known-bug: #131102
-pub struct Blorb<const N: u16>([String; N]);
-pub struct Wrap(Blorb<0>);
-pub const fn i(_: Wrap) {}
diff --git a/tests/ui/consts/bad-array-size-in-type-err.rs b/tests/ui/consts/bad-array-size-in-type-err.rs
index cb02ad3205d..0490a9d3620 100644
--- a/tests/ui/consts/bad-array-size-in-type-err.rs
+++ b/tests/ui/consts/bad-array-size-in-type-err.rs
@@ -8,3 +8,14 @@ fn main() {
     //~^ ERROR mismatched types
     //~| ERROR the constant `2` is not of type `usize`
 }
+
+fn iter(val: BadArraySize::<2>) {
+    for _ in val.arr {}
+    //~^ ERROR the constant `2` is not of type `usize`
+    //~| ERROR `[i32; 2]` is not an iterator
+}
+
+// issue #131102
+pub struct Blorb<const N: u16>([String; N]); //~ ERROR the constant `N` is not of type `usize`
+pub struct Wrap(Blorb<0>);
+pub const fn i(_: Wrap) {} //~ ERROR destructor of `Wrap` cannot be evaluated at compile-time
diff --git a/tests/ui/consts/bad-array-size-in-type-err.stderr b/tests/ui/consts/bad-array-size-in-type-err.stderr
index c3ff216432e..84e16f8d931 100644
--- a/tests/ui/consts/bad-array-size-in-type-err.stderr
+++ b/tests/ui/consts/bad-array-size-in-type-err.stderr
@@ -6,6 +6,14 @@ LL |     arr: [i32; N],
    |
    = note: the length of array `[i32; N]` must be type `usize`
 
+error: the constant `N` is not of type `usize`
+  --> $DIR/bad-array-size-in-type-err.rs:19:32
+   |
+LL | pub struct Blorb<const N: u16>([String; N]);
+   |                                ^^^^^^^^^^^ expected `usize`, found `u16`
+   |
+   = note: the length of array `[String; N]` must be type `usize`
+
 error[E0308]: mismatched types
   --> $DIR/bad-array-size-in-type-err.rs:7:38
    |
@@ -20,6 +28,37 @@ LL |     let _ = BadArraySize::<2> { arr: [0, 0, 0] };
    |
    = note: the length of array `[i32; 2]` must be type `usize`
 
-error: aborting due to 3 previous errors
+error: the constant `2` is not of type `usize`
+  --> $DIR/bad-array-size-in-type-err.rs:13:14
+   |
+LL |     for _ in val.arr {}
+   |              ^^^^^^^ expected `usize`, found `u8`
+   |
+   = note: the length of array `[i32; 2]` must be type `usize`
+
+error[E0277]: `[i32; 2]` is not an iterator
+  --> $DIR/bad-array-size-in-type-err.rs:13:14
+   |
+LL |     for _ in val.arr {}
+   |              ^^^^^^^ `[i32; 2]` is not an iterator; try calling `.into_iter()` or `.iter()`
+   |
+   = help: the trait `IntoIterator` is not implemented for `[i32; 2]`
+   = help: the following other types implement trait `IntoIterator`:
+             &[T; N]
+             &[T]
+             &mut [T; N]
+             &mut [T]
+             [T; N]
+
+error[E0493]: destructor of `Wrap` cannot be evaluated at compile-time
+  --> $DIR/bad-array-size-in-type-err.rs:21:16
+   |
+LL | pub const fn i(_: Wrap) {}
+   |                ^         - value is dropped here
+   |                |
+   |                the destructor for this type cannot be evaluated in constant functions
+
+error: aborting due to 7 previous errors
 
-For more information about this error, try `rustc --explain E0308`.
+Some errors have detailed explanations: E0277, E0308, E0493.
+For more information about an error, try `rustc --explain E0277`.