fix previous failures and address review

2 files changed, 70 insertions, 58 deletions

diff --git a/src/test/ui/const-generics/issues/issue-83765.rs b/src/test/ui/const-generics/issues/issue-83765.rs
index 67d813819e7..71c164ab0a5 100644
--- a/src/test/ui/const-generics/issues/issue-83765.rs
+++ b/src/test/ui/const-generics/issues/issue-83765.rs
@@ -2,103 +2,115 @@
 #![allow(incomplete_features)]
 
 trait TensorDimension {
-    const DIM : usize;
-    //~^ ERROR cycle detected when resolving instance `<LazyUpdim<T, {T::DIM}, DIM>
-    const ISSCALAR : bool = Self::DIM == 0;
-    fn is_scalar(&self) -> bool {Self::ISSCALAR}
+    const DIM: usize;
+    //~^ ERROR cycle detected when resolving instance
+    // FIXME Given the current state of the compiler its expected that we cycle here,
+    // but the cycle is still wrong.
+    const ISSCALAR: bool = Self::DIM == 0;
+    fn is_scalar(&self) -> bool {
+        Self::ISSCALAR
+    }
 }
 
-trait TensorSize : TensorDimension {
-    fn size(&self) -> [usize;Self::DIM];
-    fn inbounds(&self,index : [usize;Self::DIM]) -> bool {
-        index.iter().zip(self.size().iter()).all(|(i,s)| i < s)
+trait TensorSize: TensorDimension {
+    fn size(&self) -> [usize; Self::DIM];
+    fn inbounds(&self, index: [usize; Self::DIM]) -> bool {
+        index.iter().zip(self.size().iter()).all(|(i, s)| i < s)
     }
 }
 
-
 trait Broadcastable: TensorSize + Sized {
     type Element;
-    fn bget(&self, index:[usize;Self::DIM]) -> Option<Self::Element>;
-    fn lazy_updim<const NEWDIM : usize>(&self, size : [usize;NEWDIM] ) ->
-       LazyUpdim<Self,{Self::DIM},NEWDIM>
-    {
-        assert!(NEWDIM >= Self::DIM,
-            "Updimmed tensor cannot have fewer indices than the initial one.");
-        LazyUpdim {size,reference:&self}
+    fn bget(&self, index: [usize; Self::DIM]) -> Option<Self::Element>;
+    fn lazy_updim<const NEWDIM: usize>(
+        &self,
+        size: [usize; NEWDIM],
+    ) -> LazyUpdim<Self, { Self::DIM }, NEWDIM> {
+        assert!(
+            NEWDIM >= Self::DIM,
+            "Updimmed tensor cannot have fewer indices than the initial one."
+        );
+        LazyUpdim { size, reference: &self }
     }
-    fn bmap<T,F :Fn(Self::Element) -> T>(&self,foo : F) -> BMap<T,Self,F,{Self::DIM}>{
-        BMap {reference:self,closure : foo}
+    fn bmap<T, F: Fn(Self::Element) -> T>(&self, foo: F) -> BMap<T, Self, F, { Self::DIM }> {
+        BMap { reference: self, closure: foo }
     }
 }
 
-
-struct LazyUpdim<'a,T : Broadcastable,const OLDDIM : usize, const DIM : usize> {
-    size : [usize;DIM],
-    reference : &'a T
+struct LazyUpdim<'a, T: Broadcastable, const OLDDIM: usize, const DIM: usize> {
+    size: [usize; DIM],
+    reference: &'a T,
 }
 
-impl<'a,T : Broadcastable,const DIM : usize> TensorDimension for LazyUpdim<'a,T,{T::DIM},DIM> {
-    const DIM : usize = DIM;
+impl<'a, T: Broadcastable, const DIM: usize> TensorDimension for LazyUpdim<'a, T, { T::DIM }, DIM> {
+    const DIM: usize = DIM;
 }
 
-impl<'a,T : Broadcastable,const DIM : usize> TensorSize for LazyUpdim<'a,T,{T::DIM},DIM> {
-    fn size(&self) -> [usize;DIM] {self.size}
+impl<'a, T: Broadcastable, const DIM: usize> TensorSize for LazyUpdim<'a, T, { T::DIM }, DIM> {
+    fn size(&self) -> [usize; DIM] {
+        self.size
+    }
 }
 
-impl<'a,T : Broadcastable,const DIM : usize>  Broadcastable for LazyUpdim<'a,T,{T::DIM},DIM>
-{
+impl<'a, T: Broadcastable, const DIM: usize> Broadcastable for LazyUpdim<'a, T, { T::DIM }, DIM> {
     type Element = T::Element;
-    fn bget(&self,index:[usize;DIM]) -> Option<Self::Element> {
+    fn bget(&self, index: [usize; DIM]) -> Option<Self::Element> {
         assert!(DIM >= T::DIM);
-        if !self.inbounds(index) {return None}
+        if !self.inbounds(index) {
+            return None;
+        }
         let size = self.size();
-        let newindex : [usize;T::DIM] = Default::default();
+        let newindex: [usize; T::DIM] = Default::default();
         self.reference.bget(newindex)
     }
 }
 
-struct BMap<'a,R, T : Broadcastable, F :  Fn(T::Element) -> R  , const DIM: usize> {
-    reference : &'a T,
-    closure : F
+struct BMap<'a, R, T: Broadcastable, F: Fn(T::Element) -> R, const DIM: usize> {
+    reference: &'a T,
+    closure: F,
 }
 
-impl<'a,R, T : Broadcastable, F :  Fn(T::Element) -> R,
-     const DIM: usize> TensorDimension for BMap<'a,R,T,F,DIM> {
-
-    const DIM : usize = DIM;
+impl<'a, R, T: Broadcastable, F: Fn(T::Element) -> R, const DIM: usize> TensorDimension
+    for BMap<'a, R, T, F, DIM>
+{
+    const DIM: usize = DIM;
 }
-impl<'a,R, T : Broadcastable, F :  Fn(T::Element) -> R  ,
-      const DIM: usize> TensorSize for BMap<'a,R,T,F,DIM> {
-
-    fn size(&self) -> [usize;DIM] {self.reference.size()}
+impl<'a, R, T: Broadcastable, F: Fn(T::Element) -> R, const DIM: usize> TensorSize
+    for BMap<'a, R, T, F, DIM>
+{
+    fn size(&self) -> [usize; DIM] {
+        self.reference.size()
+    }
 }
 
-impl<'a,R, T : Broadcastable, F :  Fn(T::Element) -> R  ,
-  const DIM: usize> Broadcastable for BMap<'a,R,T,F,DIM> {
-
+impl<'a, R, T: Broadcastable, F: Fn(T::Element) -> R, const DIM: usize> Broadcastable
+    for BMap<'a, R, T, F, DIM>
+{
     type Element = R;
-    fn bget(&self,index:[usize;DIM]) -> Option<Self::Element> {
+    fn bget(&self, index: [usize; DIM]) -> Option<Self::Element> {
         self.reference.bget(index).map(&self.closure)
     }
 }
 
 impl<T> TensorDimension for Vec<T> {
-    const DIM : usize = 1;
+    const DIM: usize = 1;
 }
 impl<T> TensorSize for Vec<T> {
-    fn size(&self) -> [usize;1] {[self.len()]}
+    fn size(&self) -> [usize; 1] {
+        [self.len()]
+    }
 }
 impl<T: Clone> Broadcastable for Vec<T> {
     type Element = T;
-    fn bget(& self,index : [usize;1]) -> Option<T> {
+    fn bget(&self, index: [usize; 1]) -> Option<T> {
         self.get(index[0]).cloned()
     }
 }
 
 fn main() {
-    let v = vec![1,2,3];
-    let bv = v.lazy_updim([3,4]);
-    let bbv = bv.bmap(|x| x*x);
+    let v = vec![1, 2, 3];
+    let bv = v.lazy_updim([3, 4]);
+    let bbv = bv.bmap(|x| x * x);
 
-    println!("The size of v is {:?}",bbv.bget([0,2]).expect("Out of bounds."));
+    println!("The size of v is {:?}", bbv.bget([0, 2]).expect("Out of bounds."));
 }
diff --git a/src/test/ui/const-generics/issues/issue-83765.stderr b/src/test/ui/const-generics/issues/issue-83765.stderr
index 0003969f7ac..8705a39fa4b 100644
--- a/src/test/ui/const-generics/issues/issue-83765.stderr
+++ b/src/test/ui/const-generics/issues/issue-83765.stderr
@@ -1,16 +1,16 @@
-error[E0391]: cycle detected when resolving instance `<LazyUpdim<T, {T::DIM}, DIM> as TensorDimension>::DIM`
+error[E0391]: cycle detected when resolving instance `<LazyUpdim<T, { T::DIM }, DIM> as TensorDimension>::DIM`
   --> $DIR/issue-83765.rs:5:5
    |
-LL |     const DIM : usize;
-   |     ^^^^^^^^^^^^^^^^^^
+LL |     const DIM: usize;
+   |     ^^^^^^^^^^^^^^^^^
    |
 note: ...which requires checking if `TensorDimension` fulfills its obligations...
   --> $DIR/issue-83765.rs:4:1
    |
 LL | trait TensorDimension {
    | ^^^^^^^^^^^^^^^^^^^^^
-   = note: ...which again requires resolving instance `<LazyUpdim<T, {T::DIM}, DIM> as TensorDimension>::DIM`, completing the cycle
-   = note: cycle used when normalizing `<LazyUpdim<T, {T::DIM}, DIM> as TensorDimension>::DIM`
+   = note: ...which again requires resolving instance `<LazyUpdim<T, { T::DIM }, DIM> as TensorDimension>::DIM`, completing the cycle
+   = note: cycle used when normalizing `<LazyUpdim<T, { T::DIM }, DIM> as TensorDimension>::DIM`
 
 error: aborting due to previous error