Fix ICE when suggesting dereferencing binop operands

Author: sjwang05

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -860,6 +860,11 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             && let hir::Node::Expr(lhs) = self.tcx.hir_node(*lhs_hir_id)
             && let hir::Node::Expr(rhs) = self.tcx.hir_node(*rhs_hir_id)
             && let Some(rhs_ty) = typeck_results.expr_ty_opt(rhs)
+            && let trait_pred = predicate.unwrap_or(trait_pred)
+            && hir::lang_items::OPERATORS.iter().any(|&op| {
+                // Ensure we only run this code on operators
+                self.tcx.require_lang_item(op, None) == trait_pred.skip_binder().trait_ref.def_id
+            })
         {
             // Suggest dereferencing the LHS, RHS, or both terms of a binop if possible
 
@@ -891,9 +896,10 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 trait_ref: ty::TraitRef::new(
                                     self.tcx,
                                     inner.trait_ref.def_id,
-                                    self.tcx.mk_args(
-                                        &[&[l_ty.into(), r_ty.into()], &inner.trait_ref.args[2..]]
-                                            .concat(),
+                                    self.tcx.mk_args_trait(
+                                        l_ty,
+                                        iter::once(r_ty.into())
+                                            .chain(inner.trait_ref.args.iter().skip(2)),
                                     ),
                                 ),
                                 ..inner

tests/ui/binop/binary-op-suggest-deref.rs

@@ -72,4 +72,12 @@ fn baz() {
     //~^ERROR can't compare `str` with `&String` [E0277]
 }
 
+fn qux() {
+    // Issue #119352
+    const FOO: i32 = 42;
+    let _ = FOO & (*"Sized".to_string().into_boxed_str());
+    //~^ ERROR the size for values of type `str` cannot be known at compilation time
+    //~| ERROR no implementation for `i32 & str` [E0277]
+}
+
 fn main() {}

tests/ui/binop/binary-op-suggest-deref.stderr

@@ -300,7 +300,28 @@ help: consider dereferencing here
 LL |     _ = partial[..3] == *string_ref;
    |                         +
 
-error: aborting due to 22 previous errors
+error[E0277]: no implementation for `i32 & str`
+  --> $DIR/binary-op-suggest-deref.rs:78:17
+   |
+LL |     let _ = FOO & (*"Sized".to_string().into_boxed_str());
+   |                 ^ no implementation for `i32 & str`
+   |
+   = help: the trait `BitAnd<str>` is not implemented for `i32`
+   = help: the following other types implement trait `BitAnd<Rhs>`:
+             <i32 as BitAnd>
+             <i32 as BitAnd<&i32>>
+             <&'a i32 as BitAnd<i32>>
+             <&i32 as BitAnd<&i32>>
+
+error[E0277]: the size for values of type `str` cannot be known at compilation time
+  --> $DIR/binary-op-suggest-deref.rs:78:17
+   |
+LL |     let _ = FOO & (*"Sized".to_string().into_boxed_str());
+   |                 ^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `str`
+
+error: aborting due to 24 previous errors
 
 Some errors have detailed explanations: E0277, E0308, E0369.
 For more information about an error, try `rustc --explain E0277`.