fix(rustc_lint): better detect when parens are necessary

Fixes #90807

Author: notriddle

compiler/rustc_lint/src/unused.rs

@@ -476,8 +476,11 @@ trait UnusedDelimLint {
 
         lhs_needs_parens
             || (followed_by_block
-                && match inner.kind {
+                && match &inner.kind {
                     ExprKind::Ret(_) | ExprKind::Break(..) | ExprKind::Yield(..) => true,
+                    ExprKind::Range(_lhs, Some(rhs), _limits) => {
+                        !classify::expr_requires_semi_to_be_stmt(&rhs)
+                    }
                     _ => parser::contains_exterior_struct_lit(&inner),
                 })
     }

src/test/ui/lint/unused/issue-90807-unused-paren.rs

@@ -0,0 +1,8 @@
+// check-pass
+// Make sure unused parens lint doesn't emit a false positive.
+// See https://github.com/rust-lang/rust/issues/90807
+#![deny(unused_parens)]
+
+fn main() {
+    for _ in (1..{ 2 }) {}
+}