Fixed bug that resulted in a false negative when assigning to type tuple[Never]. This addresses #8237.

packages/pyright-internal/src/analyzer/types.ts

@@ -825,9 +825,7 @@ export namespace ClassType {
             newClassType.includeSubclasses = true;
         }
 
-        newClassType.tupleTypeArguments = tupleTypeArguments?.map((t) =>
-            isNever(t.type) ? { type: UnknownType.create(), isUnbounded: t.isUnbounded, isOptional: t.isOptional } : t
-        );
+        newClassType.tupleTypeArguments = tupleTypeArguments ? [...tupleTypeArguments] : undefined;
 
         if (isEmptyContainer !== undefined) {
             newClassType.isEmptyContainer = isEmptyContainer;

packages/pyright-internal/src/tests/samples/tuple1.py

@@ -1,7 +1,8 @@
 # This sample file tests various aspects of type analysis for tuples.
 
 import os
-from typing import Any, Callable
+from typing import Any, Callable, Never
+
 from typing_extensions import (  # pyright: ignore[reportMissingModuleSource]
     TypeVarTuple,
     Unpack,
@@ -270,3 +271,13 @@ def func19(a: tuple[int, ...], b: tuple[int, *tuple[int, ...]]):
 
     # This should generate an error.
     b5: tuple[int, int, *tuple[int, ...]] = b
+
+
+def func20(v: tuple[Never]):
+    # This should generate an error.
+    x1: tuple[Never] = (1,)
+
+    # This should generate an error.
+    x2: tuple[Never] = ()
+
+    x3: tuple[Never] = v

packages/pyright-internal/src/tests/typeEvaluator8.test.ts

@@ -440,7 +440,7 @@ test('Optional2', () => {
 test('Tuple1', () => {
     const analysisResults = TestUtils.typeAnalyzeSampleFiles(['tuple1.py']);
 
-    TestUtils.validateResults(analysisResults, 24);
+    TestUtils.validateResults(analysisResults, 26);
 });
 
 test('Tuple2', () => {