Rollup merge of #68288 - RalfJung:fmt, r=oli-obk

Fix some of the rustfmt fallout in Miri

re-post of #67833 without the `rustfmt::skip`

r? @oli-obk

Author: Dylan-DPC

src/librustc/mir/interpret/error.rs

@@ -33,7 +33,7 @@ impl ErrorHandled {
             ErrorHandled::Reported => {}
             ErrorHandled::TooGeneric => bug!(
                 "MIR interpretation failed without reporting an error \
-                                              even though it was fully monomorphized"
+                 even though it was fully monomorphized"
             ),
         }
     }

src/librustc/mir/interpret/mod.rs

@@ -403,8 +403,8 @@ impl<'tcx> AllocMap<'tcx> {
         let next = self.next_id;
         self.next_id.0 = self.next_id.0.checked_add(1).expect(
             "You overflowed a u64 by incrementing by 1... \
-                     You've just earned yourself a free drink if we ever meet. \
-                     Seriously, how did you do that?!",
+             You've just earned yourself a free drink if we ever meet. \
+             Seriously, how did you do that?!",
         );
         next
     }

src/librustc_mir/interpret/memory.rs

@@ -580,10 +580,9 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
                 let layout = self.tcx.layout_of(ParamEnv::empty().and(ty)).unwrap();
                 Ok((layout.size, layout.align.abi))
             }
-            Some(GlobalAlloc::Memory(alloc)) =>
-            // Need to duplicate the logic here, because the global allocations have
-            // different associated types than the interpreter-local ones.
-            {
+            Some(GlobalAlloc::Memory(alloc)) => {
+                // Need to duplicate the logic here, because the global allocations have
+                // different associated types than the interpreter-local ones.
                 Ok((alloc.size, alloc.align))
             }
             Some(GlobalAlloc::Function(_)) => bug!("We already checked function pointers above"),

src/librustc_mir/interpret/operand.rs

@@ -684,16 +684,14 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                             let variant_index = variants_start
                                 .checked_add(variant_index_relative)
                                 .expect("oveflow computing absolute variant idx");
-                            assert!(
-                                (variant_index as usize)
-                                    < rval
-                                        .layout
-                                        .ty
-                                        .ty_adt_def()
-                                        .expect("tagged layout for non adt")
-                                        .variants
-                                        .len()
-                            );
+                            let variants_len = rval
+                                .layout
+                                .ty
+                                .ty_adt_def()
+                                .expect("tagged layout for non adt")
+                                .variants
+                                .len();
+                            assert!((variant_index as usize) < variants_len);
                             (u128::from(variant_index), VariantIdx::from_u32(variant_index))
                         } else {
                             (u128::from(dataful_variant.as_u32()), dataful_variant)

src/librustc_mir/interpret/place.rs

@@ -432,12 +432,11 @@ where
             // happens at run-time so that's okay.
             let align = match self.size_and_align_of(base.meta, field_layout)? {
                 Some((_, align)) => align,
-                None if offset == Size::ZERO =>
-                // An extern type at offset 0, we fall back to its static alignment.
-                // FIXME: Once we have made decisions for how to handle size and alignment
-                // of `extern type`, this should be adapted.  It is just a temporary hack
-                // to get some code to work that probably ought to work.
-                {
+                None if offset == Size::ZERO => {
+                    // An extern type at offset 0, we fall back to its static alignment.
+                    // FIXME: Once we have made decisions for how to handle size and alignment
+                    // of `extern type`, this should be adapted.  It is just a temporary hack
+                    // to get some code to work that probably ought to work.
                     field_layout.align.abi
                 }
                 None => bug!("Cannot compute offset for extern type field at non-0 offset"),

src/librustc_mir/interpret/validity.rs

@@ -114,14 +114,11 @@ fn write_path(out: &mut String, path: &Vec<PathElem>) {
             ClosureVar(name) => write!(out, ".<closure-var({})>", name),
             TupleElem(idx) => write!(out, ".{}", idx),
             ArrayElem(idx) => write!(out, "[{}]", idx),
-            Deref =>
-            // This does not match Rust syntax, but it is more readable for long paths -- and
+            // `.<deref>` does not match Rust syntax, but it is more readable for long paths -- and
             // some of the other items here also are not Rust syntax.  Actually we can't
             // even use the usual syntax because we are just showing the projections,
             // not the root.
-            {
-                write!(out, ".<deref>")
-            }
+            Deref => write!(out, ".<deref>"),
             Tag => write!(out, ".<enum-tag>"),
             DynDowncast => write!(out, ".<dyn-downcast>"),
         }
@@ -206,9 +203,8 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValidityVisitor<'rt, 'mir, 'tcx, M
             ty::Adt(def, ..) if def.is_enum() => {
                 // we might be projecting *to* a variant, or to a field *in*a variant.
                 match layout.variants {
-                    layout::Variants::Single { index } =>
-                    // Inside a variant
-                    {
+                    layout::Variants::Single { index } => {
+                        // Inside a variant
                         PathElem::Field(def.variants[index].fields[field].ident.name)
                     }
                     _ => bug!(),