Changes:

• 276448f Fixed package-lock files
• 783ee67 Published 1.1.407
• f9fc2aa Updated typeshed stubs to the latest version (#11051)
• 5f599f9 Added error reporting for unknown or unsupported config settings. This addresses #11040. (#11045)
• cadded6 Fixed regression that results in --createstub doing nothing. This addresses #11043. (#11044)
• 538053d Fixed bug that causes a false negative when a TypedDict overrides a parent with extra_items that are not ReadOnly with a ReadOnly field. This addresses #11037. (#11038)
• ba3f0d4 Fixed bug that results in a false positive when a namedtuple functional form is used with a field starting with an underscore and rename=True. This addresses #11033. (#11034)
• 80eb0dc Fixed bug in type narrowing for literal patterns. The runtime uses equality checks, so matching against the pattern 3 cannot necessarily narrow the type to Literal[3]. This addresses #11026. (#11028)
• b1c9ae2 Fixed bug that results in a false positive error when a with statement has a single parenthesized context manager. This addresses #11020. (#11024)
• 346f74c Fixed a bug that causes a @dataclass_transform to fail if the decorator returns a callback protocol rather than a Callable. This addresses #11015. (#11018)

Changes:

• 308f5c0 Published 1.1.406
• 38317d6 Fixed bug that results in false positive for module attributes that are synthesized for namespace modules. This addresses #10692. (#10972)
• 676cd11 Fixed several bugs related to subscripts with unpack operators, notably when the unpack targets a tuple with a known length. This addresses #10723. (#10971)
• 8996f91 Removed remaining code that was left over from PEP 637, which was rejected.
• f7285d9 Added special casing in reportUnnecessaryComparison check for modules. This addresses #10706. (#10970)
• 907028c Added check for the use of a NewType in a class pattern. This addresses #10784. (#10969)
• 7b28a61 Updated typeshed stubs to the latest version (#10968)
• ad557b5 Fixed bug that results in incorrect behavior when partial is applied to a function with a positional-only parameter separator. This addresses #10954. (#10967)
• 6a92d60 Bump tar-fs from 2.1.3 to 2.1.4 in /packages/vscode-pyright (#10965)
• b0fb77d Fixed bug that causes workspace edits to include annotation IDs without changeAnnotations field. (#10902) [ #10671 ]

Changes:

• 7ee3058 Published 1.1.405.
• bb13689 Fixed bug that results in false positive "reportPossiblyUnboundVariable" error on keyword argument names. This addresses #10811. (#10876)
• 539aabd Updated error message for NewType used in isinstance check. I don't think this makes things clearer, but it is technically more correct. Addresses #10601.
• ce16aa1 Changed the evaluated type of __class__ from type[Self] to type[<Enclosing class]. This addresses #10685. (#10874)
• 099954d Added optimization that reduces the number of Uri objects that need to be created during type evaluation. This is an attempt to address #10832. (#10872)
• 93c98d7 Fixed bug that causes a false negative when using unquoted types in a TypedDict functional class definition if the types are forward declared. This addresses #10612. (#10869)
• 29bb1b0 Fixed bug that resulted in false negative when backslash followed by line feed occurs at end of file. This addresses #10814. (#10867)
• f3ab90b Fixed false negative when a keyword parameter in a child class method overrides a method with a **kwargs in the parent and the type is incompatible. This addresses #10815. (#10866)
• c407ded Fixed regression introduced in 1.1.343 that results in nondeterministic (order-dependent) type evaluation under certain circumstances involving recursive type aliases. This addresses #10850. (#10865)
• d97565a Revert "Added support for tracking multiple constraint sets when performing protocol matching. This allows protocols with overloaded methods to contribute independent constraint sets. This addresses #9835. (#9864)" (#10863) [ #10849 ]

Changes:

• f11dd22 Switch to Node 22 and make publish to npm wait (#10830)
• ba6a729 Update azure-pipelines-release.yml for Azure Pipelines
• 33f41a8 Published 1.1.404
• e32022c Improved performance and memory usage of import resolver by not recording import failure information unless caller asks for it. This is normally needed only when verboseOutput is enabled. (#10819)
• 572bc31 Implemented a number of performance and memory optimizations (#10816)
• 2d1aaf0 Fixed a recent regression that broke the "--threads" option in the CLI. (#10812)
• 7b90e9e Made PEP 728 (TypedDict with extra items) no longer experimental since it has been accepted by the SC. (#10804)
• de2d23d Improved startup performance for large projects by lazily computing the module name of each source file. (#10798)
• 78088b4 Bump tmp from 0.2.3 to 0.2.4 (#10771)
• f1c19c6 Bump axios from 1.10.0 to 1.11.0 (#10742)

Enhancements:

• Updated typeshed stubs to the latest version

Behavior Changes:

• Removed experimental support for PEP 736, which was rejected. (#10616)

Changes:

• f584f78 Published 1.1.402
• 0246b06 Fixed bug that results in a false positive "fully overlapping overload" error when a second overload uses a Callable with a ParamSpec but the first does not. This addresses #10587. (#10588)
• ce1c735 Improved modeling of bound and unbound methods so they properly use types.MethodType or types.FunctionType. This addresses #10514. (#10586)
• 859cc50 Added support for bidirectional type inference when assigning an expression to an unpacked tuple literal and all of the items in the tuple have a declared type. This addresses #10481. (#10585)
• 4887eb7 Fixed bug that results in confusion between two classes defined in the same file with the same name but in different functions when they are used in protocol matching. This addresses #10418. (#10584)
• 4cd01c6 Revert "Added check for mutable values of type list, dict, or set when used as default values for a dataclass field. These result in TypeErrors at runtime. This addresses #10553. (#10557)"
• f326cc6 Added reportUnreachable diagnostic check. If enabled, it emits a diagnostic for code that is determined to be structurally unreachable or unreachable via type analysis. It does not report code that is within a code block that is gated by a conditional that is statically determined to be false, such as TYPE_CHECKING and version checks. This diagnostic check is off by default even in strict mode because there are legitimate reasons for unreachable code to exist in Python code. (#10581) [ #10284 ]
• c165c3f Reverted narrowing behavior for discriminating between TypedDicts. This narrowing behavior isn't technically correct from a type safety standpoint, but until PEP 728 is accepted, it's the only practical way to do this form of discrimination. This addresses #10517. (#10579)
• 8610325 Changed behavior when @final is applied to a method but subsequent decorators (like @functools.cache or @property) subsequently transform the method into a different type. The typing spec is not clear how this should work. Pyright now honors the @final in these cases, which is consistent with mypy. This addresses #10543. (#10578)
• a52db80 Fixed bug that causes bidirectional type inference to be skipped when the target of an assignment is a member access expression (base.member) and the base expression is a module. This addresses #10539. (#10577)

Bug Fixes:

• Fixed a bug in the type narrowing logic for the S in D type guard pattern (where S is a string literal and D is a TypedDict). If the TypedDict is not closed, the absence of the key within the TypedDict definition cannot eliminate the type during narrowing.
• Fixed a bug that leads to a false negative when accessing a key on a TypedDict that is defined with extra_items=Never.
• Fixed bug that results in incorrect variance inference when a property access method uses a method-local type variable to annotate the self parameter.
• Fixed bug that results in a false positive error under certain circumstances where the second argument for a super call is a union.
• Fixed bug that results in a false negative when deriving from a stdlib protocol class and not implementing one or more abstract methods.
• Fixed bug that results in incorrect type narrowing behavior when the second argument to an isinstance call includes a union (specifically with the | operator) within a tuple expression.
• Fixed a bug that results in a spurious error when __class__() is assigned to Self.
• Added missing check for unquoted self references when calling TypeAliasType constructor manually (as opposed to using the PEP 695 type syntax).
• Fixed a bug that results in incorrect expansion of the bytes promotion type if the value is a bytes literal.
• Fixed bug in type narrowing logic for class patterns in a match statement. Negative type narrowing was incorrect when the subject is a literal type and the class is the corresponding non-literal class.

Enhancements:

• Improved handling of __slots__ members to correctly model the case where a descriptor object is stored in a __slots__ variable.
• Modified --verifytypes output to expand type aliases in its error messages to help diagnose "partially unknown" conditions.
• Enhanced x is ... type narrowing logic to narrow Any | EllipsisType to EllipsisType to match x is None narrowing logic.
• Updated typeshed stubs to the latest version.

Behavior Changes:

• Switched internal usage of builtins.function, typing.AwaitableGenerator, and typing._TypedDict to types.FunctionType, _typeshed._type_checker_internals.AwaitableGenerator, and _typeshed._type_checker_internals.TypedDictFallback, respectively.

Bug Fixes:

• Fixed bug that results in a false positive when accessing a generic attribute from an object whose type is type[X].
• Fixed bug that results in incorrect type narrowing of a variable that is shadowed in an inner-scoped comprehension.
• Fixed bug that results in a false positive error when referencing a class-scoped type alias defined as a callable.
• Fixed bug that causes bidirectional type inference not to be used in cases where a ternary expression is assigned to an annotated instance or class variable and the ternary condition narrows the type of self or cls.
• Fixed bug that results in a spurious "type already specialized" error when using a class-scoped type alias defined using a type statement or TypeAliasType constructor.
• Fixed a bug that leads to a hang when a generic type alias definition refers to itself.
• Fixed a bug that results in missing diagnostic details under certain circumstances where bidirectional type inference is attempted in the assignment of an attribute.
• Fixed a bug that results in a false positive error when calling a function with an unpacked TypedDict with extra_items when additional keyword args are passed.
• [From pylance] Fixed regression introduced in 1.1.399 that caused pyright CLI to fail to run on Linux systems.

Enhancements:

• Extended "type(x) is C" type narrowing logic to support cases where C is a union of types or a type variable with a union upper bound.
• Added support for PEP 765, which makes it a syntax error (or warning) in Python 3.14 if a return, break or continue is used to exit a finally clause.
• Added check for named tuple field names that begin with an underscore. These result in a runtime exception.

Behavior Change:

• Reverted a recent change that extended the reportPrivateImportUsage check to enforce imports from submodules whose names begin with an underscore. This change was disruptive to users of the popular pandas library because it exports a submodule named _typing. This was originally intended to be experimental or private, but it was never fully addressed. The pandas maintainers will work to fix this issue (pandas-dev/pandas#55231) over the next year. I'm going to back out this change to pyright in the meantime.

Bug Fixes:

• Fixed bug that results in incorrect type narrowing when a value whose type is a non-callable (and non-final) class is passed as the second argument to an isinstance call and the first argument is a callable type. In this case, a subclass could provide a compatible __call__ method, so the type shouldn't be narrowed to Never.
• Fixed bug that results in a false positive "missing stub file" diagnostic when importing a "py.typed" submodule from a namespace package.
• Fixed bug that results in a false negative when a type variable with an upper bound is used to annotate a parameter in a method override.
• Fixed a bug that results in a false negative for a method override that uses Self in a contravariant position.
• Fixed bug that results in a false positive error under certain circumstances involving a type variable with an upper bound of type[T] that is assigned to another type variable.
• Fixed a bug that results in a false negative when the specialization of a TypeVarTuple includes multiple unpacked tuples of unknown length.
• Fixed a bug that results in a false negative when a class that derives from type[Any] is assigned to any other type.
• Fixed bug that results in an incorrect error under certain circumstances when inferring the return type of a recursive function that has a decorator or is async.
• Fixed bug that results in a false negative when a return statement contains a call expression that invokes a NoReturn call and the argument list contains errors.
• Fixed bug that leads to a false positive in the reportUnnecessaryComparison check when one operand's type is a callable and the other is not.
• [From pylance] Fixed a bug that results in an internal assertion (and therefore a crash) when __builtins__.pyi imports from a project file.

Enhancements:

• Extended deprecateTypingAliases feature to support symbols imported from typing_extensions.
• Extended reportUnknownVariableType check to include cases where a value whose type is a generic class parameterized by Unknown is assigned to a variable with a declared type.
• Extended the check for isinstance and issubclass argument validation to flag the Literal special form, which leads to a runtime error when used in the second argument.
• Updated typeshed stubs to the latest version. This version removes support for Python 3.8, which is now out of service.

Behavior Changes:

• Removed support for ru and ur string prefixes. These were supported in Python 2.7 but are syntax errors in Python 3.x.

Bug Fixes:

• Fixed bug that results in a spurious type error when a ParamSpec is used in conjunction with a dataclass and a contextmanager.
• Fixed recent regression that results in a false negative when calling a function with a positional-only parameter whose type is generic and has a concrete default argument value.
• Fixed regression that results in an Unknown type evaluation where previously Any was generated during bidirectional type inference.
• Fixed bug that results in incorrect overload resolution when an unpacked argument is of unknown length and potentially matches multiple overloads.
• Fixed bug that results in a variable being displayed as "not accessed" if it's used in an argument expression for a call expression whose base type is a module or None.
• Fixed bug that results in a hang under certain very specific circumstances involving a protocol method that has been decorated in such a way that it can no longer be bound to the owning protocol class.
• Fixed a bug that contributes to inconsistent type evaluation results when using the "--threads" feature.
• Fixed bug that results in incorrect "literal math" result when dividing Literal[0] by a negative literal int value.
• Fixed a bug in "literal math" for shift operators. If the RHS value is negative, the operation is invalid, so literal math shouldn't be applied.
• Fixed bug in "literal math" logic for modulo and floor divide operators that affect cases where operands have different signs.

Behavior Changes:

• Changed algorithm for applying type narrowing upon assignment when one or both of the declared type or assigned type contain "Any".
• Removed special-casing for async functions that skips check for implicit return when the return type is NoReturn.

Enhancements:

• Updated typeshed stubs to the latest version.
• Extended reportPrivateImportUsage to report the use of symbols imported from private submodules in a "py.typed" or stub library.
• Extended the reportUnnecessaryComparision check to support the patterns x is None and x is not None in cases where x is provably disjoint in type.
• Added generalized support for assignment expressions (walrus operators) for type guards.
• Extended the type narrowing logic for the x == L type guard pattern so it supports the case where x is LiteralString and L is a string literal.