Douglas Creager c3de8847d5 [ty] Consider domain of BDD when checking whether always satisfiable (#21050) ... That PR title might be a bit inscrutable. Consider the two constraints `T ≤ bool` and `T ≤ int`. Since `bool ≤ int`, by transitivity `T ≤ bool` implies `T ≤ int`. (Every type that is a subtype of `bool` is necessarily also a subtype of `int`.) That means that `T ≤ bool ∧ T ≰ int` is an impossible combination of constraints, and is therefore not a valid input to any BDD. We say that that assignment is not in the _domain_ of the BDD. The implication `T ≤ bool → T ≤ int` can be rewritten as `T ≰ bool ∨ T ≤ int`. (That's the definition of implication.) If we construct that constraint set in an mdtest, we should get a constraint set that is always satisfiable. Previously, that constraint set would correctly _display_ as `always`, but a `static_assert` on it would fail. The underlying cause is that our `is_always_satisfied` method would only test if the BDD was the `AlwaysTrue` terminal node. `T ≰ bool ∨ T ≤ int` does not simplify that far, because we purposefully keep around those constraints in the BDD structure so that it's easier to compare against other BDDs that reference those constraints. To fix this, we need a more nuanced definition of "always satisfied". Instead of evaluating to `true` for _every_ input, we only need it to evaluate to `true` for every _valid_ input — that is, every input in its domain.		2025-10-24 13:37:56 -04:00
..
annotations	[ty] Infer type for implicit `self` parameters in method bodies (#20922)	2025-10-23 09:34:39 +02:00
assignment	[ty] Prefer declared type for invariant collection literals (#20927)	2025-10-16 16:11:28 -04:00
binary	[ty] Sync vendored typeshed stubs (#20876)	2025-10-15 11:13:32 +02:00
boolean	Revert "[ty] Better control flow for boolean expressions that are inside if (#18010)" (#18150)	2025-05-17 08:27:32 -04:00
boundness_declaredness	[ty] Reformulation of public symbol inference test suite (#20667)	2025-10-01 14:26:17 +02:00
call	[ty] Avoid duplicate diagnostics during multi-inference of standalone expressions (#21056)	2025-10-24 13:21:39 -04:00
class	[ty] Infer type for implicit `self` parameters in method bodies (#20922)	2025-10-23 09:34:39 +02:00
comparison	[ty] detect cycles in binary comparison inference (#20446)	2025-09-17 09:45:25 +02:00
comprehensions	[ty] Async for loops and async iterables (#19634)	2025-07-30 17:40:24 +02:00
conditional	[ty] Support as-patterns in reachability analysis (#19728)	2025-08-04 20:13:50 +02:00
dataclasses	[ty] `dataclass_transform`: Support for fields with an `alias` (#20961)	2025-10-18 18:20:39 +00:00
declaration	[ty] Format conflicting types as an enumeration (#18956)	2025-06-26 14:29:33 +02:00
diagnostics	[ty] `continue` and `break` statements outside loops are syntax errors (#20944)	2025-10-17 17:13:40 +00:00
directives	[ty] Use annotated parameters as type context (#20635)	2025-10-03 17:14:51 -04:00
doc	ty_python_semantic: add union type context to function call type errors	2025-05-09 13:40:51 -04:00
exception	[ty] Filter out `revealed-type` and `undefined-reveal` diagnostics from mdtest snapshots (#20820)	2025-10-12 18:39:32 +00:00
expression	[ty] Delegate truthiness inference of an enum `Literal` type to its enum-instance supertype (#21060)	2025-10-24 14:34:16 +01:00
function	[ty] Improve disambiguation of types via fully qualified names (#20141)	2025-08-29 08:44:18 +00:00
generics	[ty] fix infinite recursion with generic type aliases (#20969)	2025-10-23 14:14:30 +00:00
ide_support	[ty] Filter out `revealed-type` and `undefined-reveal` diagnostics from mdtest snapshots (#20820)	2025-10-12 18:39:32 +00:00
import	[ty] Improve error messages for unresolved attribute diagnostics (#20963)	2025-10-19 10:58:25 +01:00
literal	[ty] Treat functions, methods, and dynamic types as function-like `Callable`s (#20842)	2025-10-13 15:21:55 +02:00
loops	[ty] Heterogeneous unpacking support for unions (#20377)	2025-10-15 19:30:03 +01:00
narrow	[ty] Consider `__len__` when determining the truthiness of an instance of a tuple class or a `@final` class (#21049)	2025-10-24 09:29:55 +00:00
regression	[ty] Fix rare panic with highly cyclic `TypeVar` definitions (#21059)	2025-10-24 18:30:54 +02:00
scopes	[ty] Improve error messages for unresolved attribute diagnostics (#20963)	2025-10-19 10:58:25 +01:00
shadowing	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
snapshots	[ty] Improve `invalid-argument-type` diagnostics where a union type was provided (#21044)	2025-10-23 13:16:21 +00:00
stubs	Update default and latest Python versions for 3.14 (#20725)	2025-10-07 12:23:11 -04:00
subscript	[ty] Rename "possibly unbound" diagnostics to "possibly missing" (#20492)	2025-09-23 14:26:55 +00:00
suppressions	[ty] Add suggestion to unknown rule diagnostics, rename `unknown-rule` lint to `ignore-comment-unknown-rule` (#20948)	2025-10-18 12:44:21 +02:00
type_compendium	[ty] Heterogeneous unpacking support for unions (#20377)	2025-10-15 19:30:03 +01:00
type_of	[ty] Improve the `Display` for generic `type[]` types (#19667)	2025-07-31 19:45:01 +01:00
type_properties	[ty] Consider domain of BDD when checking whether always satisfiable (#21050)	2025-10-24 13:37:56 -04:00
type_qualifiers	[ty] Infer type for implicit `self` parameters in method bodies (#20922)	2025-10-23 09:34:39 +02:00
unary	Update class literal display to use `<class 'Foo'>` style (#17889)	2025-05-06 20:11:25 -04:00
with	[ty] Use `typing.Self` for the first parameter of instance methods (#20517)	2025-09-29 21:08:08 +02:00
.mdformat.toml	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
async.md	[ty] Support `async`/`await`, `async with` and `yield from` (#19595)	2025-07-30 11:51:21 +02:00
attributes.md	[ty] Infer type for implicit `self` parameters in method bodies (#20922)	2025-10-23 09:34:39 +02:00
bidirectional.md	[ty] bidirectional type inference using function return type annotations (#20528)	2025-10-11 00:38:35 +00:00
classes.md	[ty] don't assume that deferred type inference means deferred name resolution (#20160)	2025-08-29 16:19:45 -07:00
cycle.md	[ty] Avoid ever-growing default types (#20991)	2025-10-21 19:13:36 +02:00
decorators.md	ty_python_semantic: add union type context to function call type errors	2025-05-09 13:40:51 -04:00
del.md	[ty] No union with `Unknown` for module-global symbols (#20664)	2025-10-01 16:40:30 +02:00
deprecated.md	[ty] Consistent use of American english (in rules) (#19488)	2025-07-22 16:10:38 +02:00
descriptor_protocol.md	[ty] Infer type for implicit `self` parameters in method bodies (#20922)	2025-10-23 09:34:39 +02:00
enums.md	[ty] Enums: allow multiple aliases to point to the same member (#20669)	2025-10-01 15:51:53 +02:00
exhaustiveness_checking.md	[ty] Fix subtyping for dynamic specializations (#20592)	2025-09-26 15:05:03 +02:00
final.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
implicit_type_aliases.md	[ty] no more diverging query cycles in type expressions (#20359)	2025-09-16 16:44:11 -07:00
instance_layout_conflict.md	[ty] initial support for `slots=True` in dataclasses (#20278)	2025-09-07 18:25:35 +01:00
intersection_types.md	[ty] Expansion of enums into unions of literals (#19382)	2025-07-21 19:37:55 +02:00
invalid_syntax.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
known_constants.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
mdtest_config.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
mdtest_custom_typeshed.md	[ty] Remove `Type::Tuple` (#19669)	2025-08-11 22:03:32 +01:00
metaclass.md	Update class literal display to use `<class 'Foo'>` style (#17889)	2025-05-06 20:11:25 -04:00
mro.md	[ty] Filter out `revealed-type` and `undefined-reveal` diagnostics from mdtest snapshots (#20820)	2025-10-12 18:39:32 +00:00
named_tuple.md	[ty] Infer type for implicit `self` parameters in method bodies (#20922)	2025-10-23 09:34:39 +02:00
overloads.md	[ty] Improve diagnostics for bad `@overload` definitions (#20745)	2025-10-07 21:52:57 +00:00
pep613_type_aliases.md	[ty] Fall back to `Divergent` for deeply nested specializations (#20988)	2025-10-22 14:29:10 +02:00
pep695_type_aliases.md	[ty] Add cycle handling to `lazy_default` (#20967)	2025-10-23 10:05:08 +02:00
properties.md	[ty] `"foo".startswith` is not an instance of `types.MethodWrapperType` (#20317)	2025-09-10 11:14:26 +00:00
protocols.md	[ty] Fix panic when attempting to validate the members of a protocol that inherits from a protocol in another module (#20956)	2025-10-18 15:01:46 +01:00
public_types.md	[ty] Disambiguate classes that live in different modules but have the same fully qualified names (#20756)	2025-10-08 18:27:40 +01:00
statically_known_branches.md	[ty] Rename "possibly unbound" diagnostics to "possibly missing" (#20492)	2025-09-23 14:26:55 +00:00
sys_platform.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
sys_version_info.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
t_strings.md	[ty] Add support for PEP 750 t-strings (#20085)	2025-08-25 18:49:49 +00:00
terminal_statements.md	[ty] improve lazy scope place lookup (#19321)	2025-07-25 07:11:11 +00:00
ty_extensions.md	[ty] Simplify and fix `CallableTypeOf[..]` implementation (#20797)	2025-10-10 12:04:37 +02:00
typed_dict.md	[ty] Improve error messages for unresolved attribute diagnostics (#20963)	2025-10-19 10:58:25 +01:00
union_types.md	[ty] Introduce `TypeRelation::Redundancy` (#20602)	2025-10-03 18:35:30 +01:00
unpacking.md	[ty] Infer more precise types for collection literals (#20360)	2025-09-17 18:51:50 -04:00
unreachable.md	[ty] Rename "possibly unbound" diagnostics to "possibly missing" (#20492)	2025-09-23 14:26:55 +00:00