bypass multi-inference for named expressions

Author: ibraheemdev

crates/ty_python_semantic/src/types/context.rs

@@ -594,6 +594,11 @@ impl<'db, 'ctx> DiagnosticGuardBuilder<'db, 'ctx> {
         if !ctx.db.should_check_file(ctx.file) {
             return None;
         }
+        // If this lint is being reported as part of multi-inference of a given expression,
+        // silence it to avoid duplicated diagnostics.
+        if ctx.is_in_multi_inference() {
+            return None;
+        }
         Some(DiagnosticGuardBuilder { ctx, id, severity })
     }
 

crates/ty_python_semantic/src/types/infer/builder.rs

@@ -5203,14 +5203,23 @@ impl<'db, 'ast> TypeInferenceBuilder<'db, 'ast> {
             ast::Expr::Compare(compare) => self.infer_compare_expression(compare),
             ast::Expr::Subscript(subscript) => self.infer_subscript_expression(subscript),
             ast::Expr::Slice(slice) => self.infer_slice_expression(slice),
-            ast::Expr::Named(named) => self.infer_named_expression(named),
             ast::Expr::If(if_expression) => self.infer_if_expression(if_expression),
             ast::Expr::Lambda(lambda_expression) => self.infer_lambda_expression(lambda_expression),
             ast::Expr::Call(call_expression) => self.infer_call_expression(call_expression, tcx),
             ast::Expr::Starred(starred) => self.infer_starred_expression(starred),
             ast::Expr::Yield(yield_expression) => self.infer_yield_expression(yield_expression),
             ast::Expr::YieldFrom(yield_from) => self.infer_yield_from_expression(yield_from),
             ast::Expr::Await(await_expression) => self.infer_await_expression(await_expression),
+            ast::Expr::Named(named) => {
+                // Definitions must be unique, so we bypass multi-inference for named expressions.
+                if !self.multi_inference_state.is_panic()
+                    && let Some(ty) = self.expressions.get(&expression.into())
+                {
+                    return *ty;
+                }
+
+                self.infer_named_expression(named)
+            }
             ast::Expr::IpyEscapeCommand(_) => {
                 todo_type!("Ipy escape command support")
             }