Alex Waygood bc6ea68733 [ty] Add precise iteration and unpacking inference for string literals and bytes literals (#20023) ... ## Summary Previously we held off from doing this because we weren't sure that it was worth the added complexity cost. But our code has changed in the months since we made that initial decision, and I think the structure of the code is such that it no longer really leads to much added complexity to add precise inference when unpacking a string literal or a bytes literal. The improved inference we gain from this has real benefits to users (see the mypy_primer report), and this PR doesn't appear to have a performance impact. ## Test plan mdtests		2025-08-22 19:33:08 +01:00
..
annotations	[ty] Track when type variables are inferable or not (#19786)	2025-08-16 18:25:03 -04:00
assignment	[ty] Return `Option<TupleType>` from `infer_tuple_type_expression` (#19735)	2025-08-04 13:48:19 +01:00
binary	[ty] Remove special casing for string-literal-in-tuple `__contains__` (#19642)	2025-07-31 11:28:03 +01:00
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	Update class literal display to use `<class 'Foo'>` style (#17889)	2025-05-06 20:11:25 -04:00
call	[ty] Avoid unnecessary argument type expansion (#19999)	2025-08-21 06:13:11 +00:00
class	[ty] Remove use of `ClassBase::try_from_type` from `super()` machinery (#19902)	2025-08-14 22:14:31 +01:00
comparison	[ty] Enum literal types (#19328)	2025-07-15 21:31:53 +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] correctly ignore field specifiers when not specified (#20002)	2025-08-20 11:33:23 -07:00
declaration	[ty] Format conflicting types as an enumeration (#18956)	2025-06-26 14:29:33 +02:00
diagnostics	[ty] Improve diagnostics for bad calls to functions (#20022)	2025-08-21 22:00:44 +01:00
directives	[ty] Exhaustiveness checking & reachability for `match` statements (#19508)	2025-07-23 22:45:45 +02:00
doc	ty_python_semantic: add union type context to function call type errors	2025-05-09 13:40:51 -04:00
exception	[ty] Use separate Rust types for bound and unbound type variables (#19796)	2025-08-11 15:29:58 -04:00
expression	[ty] Support `async`/`await`, `async with` and `yield from` (#19595)	2025-07-30 11:51:21 +02:00
function	[ty] Short circuit `ReachabilityConstraints::analyze_single` for dynamic types (#19867)	2025-08-11 21:58:34 +02:00
generics	[ty] Perform assignability etc checks using new `Constraints` trait (#19838)	2025-08-21 09:30:09 -04:00
ide_support	[ty] Fix attribute access on `TypedDict`s (#19758)	2025-08-05 13:59:10 +02:00
import	[ty] Add link for namespaces being partial (#20015)	2025-08-20 21:28:57 -07:00
literal	[ty] Understand classes that inherit from subscripted `Protocol[]` as generic (#17832)	2025-05-09 17:39:15 +01:00
loops	[ty] Add precise iteration and unpacking inference for string literals and bytes literals (#20023)	2025-08-22 19:33:08 +01:00
narrow	[ty] linear variance inference for PEP-695 type parameters (#18713)	2025-08-19 17:54:09 -07:00
regression	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
scopes	[ty] fix deferred name loading in PEP695 generic classes/functions (#19888)	2025-08-13 15:51:59 -07:00
shadowing	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
snapshots	[ty] Sync vendored typeshed stubs (#20031)	2025-08-21 21:32:48 +00:00
stubs	[ty] Do not carry the generic context of `Protocol` or `Generic` in the `ClassBase` enum (#17989)	2025-05-22 21:37:03 -04:00
subscript	[ty] Improve `sys.version_info` special casing (#19894)	2025-08-13 14:39:13 +01:00
suppressions	[ty] Consistent use of American english (in rules) (#19488)	2025-07-22 16:10:38 +02:00
type_compendium	[ty] Remove `Type::Tuple` (#19669)	2025-08-11 22:03:32 +01:00
type_of	[ty] Improve the `Display` for generic `type[]` types (#19667)	2025-07-31 19:45:01 +01:00
type_properties	[ty] Remove `Type::Tuple` (#19669)	2025-08-11 22:03:32 +01:00
type_qualifiers	[ty] Keep track of type qualifiers in stub declarations without right-hand side (#19756)	2025-08-05 12:07:05 +02:00
unary	Update class literal display to use `<class 'Foo'>` style (#17889)	2025-05-06 20:11:25 -04:00
with	[ty] Diagnostics for async context managers (#19704)	2025-08-05 07:41:37 -07:00
.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[tuple[int, str]]` as the meta-type of `tuple[int, str]` (#19741)	2025-08-04 13:10:47 +00:00
cycle.md	[ty] Add cycle handling for unpacking targets (#18078)	2025-05-13 21:27:48 +00:00
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] Support `__setitem__` and improve `__getitem__` related diagnostics (#19578)	2025-08-01 09:23:27 +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] Fix descriptor lookups for most types that overlap with `None` (#19120)	2025-07-05 19:34:23 +01:00
enums.md	[ty] Infer the correct type of Enum `__eq__` and `__ne__` comparisions (#19666)	2025-08-18 19:45:44 +02:00
exhaustiveness_checking.md	[ty] Add precise iteration and unpacking inference for string literals and bytes literals (#20023)	2025-08-22 19:33:08 +01:00
final.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
instance_layout_conflict.md	[ty] Remove special casing for tuple addition (#19636)	2025-07-30 16:25:42 +00:00
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] Track different uses of legacy typevars, including context when rendering typevars (#19604)	2025-08-01 12:20:32 -04:00
named_tuple.md	[ty] Detect `NamedTuple` classes where fields without default values follow fields with default values (#19945)	2025-08-19 08:56:08 +00:00
overloads.md	[ty] Track different uses of legacy typevars, including context when rendering typevars (#19604)	2025-08-01 12:20:32 -04:00
pep695_type_aliases.md	[ty] fix unpacking a type alias with detailed tuple spec (#19981)	2025-08-18 17:54:05 -07:00
properties.md	ty_python_semantic: add union type context to function call type errors	2025-05-09 13:40:51 -04:00
protocols.md	[ty] Strict validation of protocol members (#17750)	2025-08-19 22:45:41 +00:00
public_types.md	[ty] improve lazy scope place lookup (#19321)	2025-07-25 07:11:11 +00:00
statically_known_branches.md	[ty] Infer nonlocal types as unions of all reachable bindings (#18750)	2025-06-26 12:24:40 +02:00
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
terminal_statements.md	[ty] improve lazy scope place lookup (#19321)	2025-07-25 07:11:11 +00:00
ty_extensions.md	[ty] Rename type_api => ty_extensions (#19523)	2025-07-24 08:24:26 +00:00
typed_dict.md	[ty] Validate writes to `TypedDict` keys (#19782)	2025-08-06 15:19:13 -07:00
union_types.md	[ty] Expansion of enums into unions of literals (#19382)	2025-07-21 19:37:55 +02:00
unpacking.md	[ty] Add precise iteration and unpacking inference for string literals and bytes literals (#20023)	2025-08-22 19:33:08 +01:00
unreachable.md	[ty] improve lazy scope place lookup (#19321)	2025-07-25 07:11:11 +00:00