Pyright

Enhancement: Improved type inference logic for tuple expressions that contain unpacked tuples.

Bug Fix: Fixed bug that resulted in unknown types within stubs when a forward reference was made within a type alias definition.

Bug Fix: Fixed bug in bidirectional type inference logic for unpack operator.

Bug Fix: Fixed bug in assignment type narrowing for index expressions. The narrowed type was always evaluated as "None" rather than the assigned type.

Bug Fix: Fixed bug in assignment type narrowing that was triggered when the RHS and LHS were both union types and the RHS contained an `Any`.

Enhancement: Added diagnostic check for a call expression that appears within a type annotation. This was previously not flagged as an error.

Bug Fix: Fixed false negative bug in the "reportOverlappingOverload" diagnostic check. It was not correctly detecting overlapping overloads when one of the parameters in the earlier overload was annotated with at TypeVar.

Bug Fix: Fixed bug in logic that compares the type compatibility of two functions. In particular, if the source function contains a keyword argument and the dest function does not contain a keyword argument of the same name bug contains a **kwargs, the types must match.

Enhancement: Added support for overloaded `__init__` method that annotates the `self` parameter with a generic version of the class being constructed.

Behavior Change: Added a few exemptions for the reportInvalidTypeVarUse check. In particular, constrained TypeVars, bound TypeVars used as type arguments, and any TypeVar used as a type argument to a generic type alias are exempt from this check. There are legitimate uses for all of these cases.

Bug Fix: Fixed recent regression in type assignment check logic that broke certain cases where the destination and source were both unions that contained type variables.

Behavior Change: Changed behavior when evaluating type of symbol within type stubs. Previously forward references were allowed only for class types. Now, forward references are allowed (and no code flow analysis is employed) for all symbols. The new behavior is consistent with mypy's.

Enhancement: Added new diagnostic check for an overloaded function without an implementation within a source (.py) file. Fixed a bug in the diagnostic check for a single overload when an implementation is present.

Bug Fix: Fixed bug in the parsing of "with" statements where the "with item" starts with an open parenthesis.

Enhancement: Added "collections.defaultdict" to the list of classes that does not support runtime subscripting in versions of Python prior to 3.9.

Behavior Change: Changed behavior of type inference for empty list (`[]`) and empty dict (`{}`) expressions. They were previously inferred to be `List[Any]` and `Dict[Any, Any]`, but they are now inferred as `List[Unknown]` and `Dict[Unknown, Unknown]`. This affects strict mode type checking, where partially-unknown types are reported as errors. This change may require some explicit type annotations within strictly-typed code.

Bug Fix: Fixed false positive bug where "class not runtime subscriptable" error was reported even if in a type stub.

New Feature: Implemented command-line switches for pythonplatform and pythonversion. These are overridden by pyrightconfig.json settings.

New Feature: Added support for comments and trailing comments within pyrightconfig.json.

Enhancement: Updated to latest typeshed stubs.

Enhancement (from Pylance): Improve auto-import performance.

Enhancement (from Pylance): Added extra perf tracking.

Bug Fix: Fixed false positive error that incorrectly complained about the use of `Annotated` as a class with no type arguments.

Bug Fix: Fixed false positive error when using bidirectional inference of dictionary expression where the expected type key and/or value types contain literals.

Bug Fix: Fixed bug that resulted in wildcard imports (i.e. imports the form `from x import *`) to import symbols from the target that were not meant to be externally visible. This bug occurred only when the imported module had no `__all__` symbol defined.

Bug Fix: Fixed bug in validation of constrained types in TypeVars. Subtypes of constrained types should be allowed.

Enhancement: Improve source mapper (the code that maps symbols found in stub files to the corresponding code in ".py" files) to handle more cases.

Enhancement: Added diagnostic error for try statement that has no except or finally statement.

New Feature: Added "reportOverlappingOverload" diagnostic rule, splitting out a few checks that were previously in the "reportGeneralTypeIssue" rule. This allows for finer-grained control over these overload checks.

Behavior Change: Added a few additional names that can be used for "cls" parameter without triggering diagnostic. These variants are reasonable and are used within some typeshed stubs.

Enhancement: Added TypeVarTuple definition to typings.pyi stub.

Enhancement: Updated TypeVarTuple logic to detect and report an error when a tuple of unknown length is bound to an unpacked TypeVarTuple. This is illegal according to the latest version of PEP 646.

Enhancement: Special-cased the `__init_subclass__` method in the completion provider so it is offered as a suggestion even though there is no classmethod decorator present. This symbol is unfortunately inconsistent from all other class methods in that it doesn't require a classmethod decorator for some reason.

Behavior Change: Changed logic for attributes marked `ClassVar` to allow writes from an instance of the class as long as the type of the attribute is a descriptor object.

Bug Fix: Fixed a hole in type comparison logic for TypeVars that could have theoretically resulted in incorrect aliasing of types.

Bug Fix: Fixed bug that caused false positive when import statement targeted a symbol that had a nonlocal or global name binding.

Behavior Change: Enhanced method override compatibility logic to allow instance and class methods to pass generic bound types for `self` and `cls`.

New Feature: Added support for ".pth" files (often used for editable installs) when using the "venv" configuration option in pythonconfig.json.

Bug Fix: Fixed bug whereby import symbol “A” in the statement “from . import A” was not considered a public symbol in a py.typed source file, but it should be.

Enhancement: Improved handling of enum classes. If such a class is defined in a ".py" file, variables defined in the class with type annotations but no assignment are now considered instance variables within each enum instance, whereas variables assigned within the enum class are assumed to be members of the enumeration. This is consistent with the way the EnumMeta metaclass works. In stub files, type annotations without assignments are still assumed to be members of the enumeration, since that's the convention used in typeshed and other stubs.

Enhancement: Added check for parameter names when comparing functions. Parameter names that do not begin with an underscore must match in name. This also affects method override checks and protocol matching checks.

Bug Fix: Fix potential infinite recursion in source mapping, crash in doc strings

Bug Fixes: Improved support for PEP 634 (Structured Pattern Matching):
* Improved negative-case type narrowing for capture patterns. Because capture patterns capture anything, the remaining type is "Never".
* Improved type narrowing for mapping patterns used in structural pattern matching when the subject expression type contains a typed dictionary.
* Added code to detect and report cases where irrefutable patterns are used within an "or" pattern and are not the last entry.
* Added logic to verify that all "or" subpatterns target the same names as specified in PEP 634.
* Added code to detect the case where a case statement without a guard expression uses an irrefutable pattern but is not the final case statement. This is disallowed according to PEP 634.
* Fixed bug in parser that resulted in incorrect text ranges for parenthetical patterns.

Bug Fix: Improved performance for completion suggestions, especially when large numbers of suggestions are returned.

Enhancement: Updated typeshed stubs to the latest.

Enhancement: Enabled postponed type annotation evaluation by default for Python 3.10.

Bug Fix: Fixed bug that caused a false positive when a bound TypeVar was used to access a class method that was annotated with a bound TypeVar for the "cls" parameter.

Bug Fix: Fixed bug that caused index expressions to be printed incorrectly when they appeared in error messages.

Enhancement: Added type narrowing support for index expressions that use a numeric (integral) literal subscript value.

Enhancement: Improved the logic that determines whether a call expression within the code flow graph is a "NoReturn" call. It now provides better handling of unions when evaluating the call type.

Enhancement: Added support for parenthesized list of context managers in "with" statement for Python 3.10.

Bug Fix: Fixed bug that prevented the use of a generic type alias defined using a PEP 593-style "Annotated" with a bare TypeVar.

Bug Fix: Fixed false negative when PEP 585 type is used in a type alias or other cases where postponed evaluation is not possible.

Bug Fix: Fixed regression that resulted in error when "match" is used in expressions but is mistaken for a pattern-matching statement.

Bug Fix: Fixed schema for "python.analysis.logLevel" setting. The default value was specified incorrectly. Thanks to Rafał Chłodnicki for this fix.

Bug Fix: Fixed a bug that caused a false positive when a TypeVar is bound to a generic protocol class.

Bug Fix: Fixed a bug that caused a false positive when a boolean operator was applied to a type variable and the corresponding magic method used an explicit type annotation for the "self" parameter.

Enhancement: Added a new diagnostic check for out-of-range indexes for tuples that have known lengths.

Enhancement: Added limited support for negative type narrowing in pattern matching. For example, if the type of the subject expression is bool and the matching pattern is `False | x`, the type of `x` will be inferred to be `True`.

Bug Fix: Fixed bug that affected generic type aliases that contained Callable types that are parameterized by a type variable.

Enhancement: Extended abstract method checks to Protocol classes even though they don't explicitly derive from ABCMeta.

Bug Fix: Fixed bug in type narrowing for class patterns in "case" statements.

New Feature: Implemented PEP 634 support for structural pattern matching. This new PEP was just accepted, and the functionality will appear in the next alpha release of Python 3.10.

Bug Fix: Fixed bug that caused a false positive error when declaring a class within a local scope when the symbol is nonlocal or global.

Enhancement: Improved handling of unpacked arguments when the type is a union of known-length tuples.