Expand the scope of useless-expression (B018) (#3455)

2023-03-23 18:33:58 -04:00
parent aea925a898
commit e8d17d23cb
8 changed files with 146 additions and 56 deletions
--- a/crates/ruff_python_ast/src/helpers.rs
+++ b/crates/ruff_python_ast/src/helpers.rs
@@ -131,6 +131,39 @@ pub fn contains_effect(ctx: &Context, expr: &Expr) -> bool {
            }
        }

+        // Avoid false positive for overloaded operators.
+        if let ExprKind::BinOp { left, right, .. } = &expr.node {
+            if !matches!(
+                left.node,
+                ExprKind::Constant { .. }
+                    | ExprKind::JoinedStr { .. }
+                    | ExprKind::List { .. }
+                    | ExprKind::Tuple { .. }
+                    | ExprKind::Set { .. }
+                    | ExprKind::Dict { .. }
+                    | ExprKind::ListComp { .. }
+                    | ExprKind::SetComp { .. }
+                    | ExprKind::DictComp { .. }
+            ) {
+                return true;
+            }
+            if !matches!(
+                right.node,
+                ExprKind::Constant { .. }
+                    | ExprKind::JoinedStr { .. }
+                    | ExprKind::List { .. }
+                    | ExprKind::Tuple { .. }
+                    | ExprKind::Set { .. }
+                    | ExprKind::Dict { .. }
+                    | ExprKind::ListComp { .. }
+                    | ExprKind::SetComp { .. }
+                    | ExprKind::DictComp { .. }
+            ) {
+                return true;
+            }
+            return false;
+        }
+
        // Otherwise, avoid all complex expressions.
        matches!(
            expr.node,