Fixed bug that resulted in a false negative when assigning to type `t…

…uple[Never]`. This addresses #8237.
microsoft · Jun 26, 2024 · 427ca11 · 427ca11
1 parent b5d4d92
commit 427ca11
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Showing 3 changed files with 14 additions and 5 deletions.
diff --git a/packages/pyright-internal/src/analyzer/types.ts b/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;

diff --git a/packages/pyright-internal/src/tests/samples/tuple1.py b/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
diff --git a/packages/pyright-internal/src/tests/typeEvaluator8.test.ts b/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', () => {