[ty] narrow the right-hand side of `==`, `!=`, `is` and `is not` conditions when the left-hand side is not narrowable by drbh · Pull Request #22511 · astral-sh/ruff

drbh · 2026-01-11T23:56:30Z

Summary

This PR narrows the rhs operand similar to the existing functionality on lhs operands seen here

Test Plan

repro.py

from typing import reveal_type

def _(flag: bool):
    x = None if flag else 1

    if None != x:
        reveal_type(x)  # revealed: Literal[1]
    else:
        reveal_type(x)  # revealed: None

def _(flag: bool):
    x = None if flag else 1

    if None == x:
        reveal_type(x)  # revealed: None
    else:
        reveal_type(x)  # revealed: Literal[1]

run with

cargo run --bin ty -- check --python-version 3.12 repro.py

output

info[revealed-type]: Revealed type
 --> repro.py:7:21
  |
6 |     if None != x:
7 |         reveal_type(x)  # revealed: Literal[1]
  |                     ^ `Literal[1]`
8 |     else:
9 |         reveal_type(x)  # revealed: None
  |

info[revealed-type]: Revealed type
  --> repro.py:9:21
   |
 7 |         reveal_type(x)  # revealed: Literal[1]
 8 |     else:
 9 |         reveal_type(x)  # revealed: None
   |                     ^ `None`
10 |
11 | def _(flag: bool):
   |

info[revealed-type]: Revealed type
  --> repro.py:15:21
   |
14 |     if None == x:
15 |         reveal_type(x)  # revealed: None
   |                     ^ `None`
16 |     else:
17 |         reveal_type(x)  # revealed: Literal[1]
   |

info[revealed-type]: Revealed type
  --> repro.py:17:21
   |
15 |         reveal_type(x)  # revealed: None
16 |     else:
17 |         reveal_type(x)  # revealed: Literal[1]
   |                     ^ `Literal[1]`
   |

Found 4 diagnostics

Compared with

this output is an improvement over both mypy and pyright which incorrectly narrow the type

uvx mypy repro.py
repro.py:7: note: Revealed type is "builtins.int"
repro.py:9: note: Revealed type is "None | builtins.int"
repro.py:15: note: Revealed type is "None | builtins.int"
repro.py:17: note: Revealed type is "builtins.int"
Success: no issues found in 1 source file

uvx pyright repro.py
/Users/drbh/Projects/ruff/repro.py
  /Users/drbh/Projects/ruff/repro.py:7:21 - information: Type of "x" is "Literal[1] | None"
  /Users/drbh/Projects/ruff/repro.py:9:21 - information: Type of "x" is "Literal[1] | None"
  /Users/drbh/Projects/ruff/repro.py:15:21 - information: Type of "x" is "Literal[1] | None"
  /Users/drbh/Projects/ruff/repro.py:17:21 - information: Type of "x" is "Literal[1] | None"
0 errors, 0 warnings, 4 informations

astral-sh-bot · 2026-01-12T00:00:09Z

Diagnostic diff on typing conformance tests

No changes detected when running ty on typing conformance tests ✅

astral-sh-bot · 2026-01-12T00:03:26Z

`mypy_primer` results

Changes were detected when running on open source projects

prefect (https://github.com/PrefectHQ/prefect)
+ src/integrations/prefect-dbt/prefect_dbt/cli/commands.py:461:21: error[invalid-await] `Unknown | None | Coroutine[Any, Any, Unknown | None]` is not awaitable
+ src/integrations/prefect-dbt/prefect_dbt/cli/commands.py:535:21: error[invalid-await] `Unknown | None | Coroutine[Any, Any, Unknown | None]` is not awaitable
+ src/integrations/prefect-dbt/prefect_dbt/cli/commands.py:610:21: error[invalid-await] `Unknown | None | Coroutine[Any, Any, Unknown | None]` is not awaitable
+ src/integrations/prefect-dbt/prefect_dbt/cli/commands.py:685:21: error[invalid-await] `Unknown | None | Coroutine[Any, Any, Unknown | None]` is not awaitable
+ src/integrations/prefect-dbt/prefect_dbt/cli/commands.py:760:21: error[invalid-await] `Unknown | None | Coroutine[Any, Any, Unknown | None]` is not awaitable
+ src/integrations/prefect-dbt/prefect_dbt/cli/commands.py:835:21: error[invalid-await] `Unknown | None | Coroutine[Any, Any, Unknown | None]` is not awaitable
- src/integrations/prefect-dbt/prefect_dbt/core/settings.py:94:28: error[invalid-assignment] Object of type `T@resolve_block_document_references | dict[str, Any]` is not assignable to `dict[str, Any]`
+ src/integrations/prefect-dbt/prefect_dbt/core/settings.py:94:28: error[invalid-assignment] Object of type `T@resolve_block_document_references | dict[str, Any] | str | ... omitted 4 union elements` is not assignable to `dict[str, Any]`
- src/integrations/prefect-dbt/prefect_dbt/core/settings.py:99:28: error[invalid-assignment] Object of type `T@resolve_variables | dict[str, Any]` is not assignable to `dict[str, Any]`
+ src/integrations/prefect-dbt/prefect_dbt/core/settings.py:99:28: error[invalid-assignment] Object of type `T@resolve_variables | str | int | ... omitted 4 union elements` is not assignable to `dict[str, Any]`
+ src/integrations/prefect-docker/tests/test_containers.py:27:47: error[invalid-argument-type] Argument is incorrect: Expected `str`, found `str | bool | dict[Unknown | str, Unknown | int] | None`
+ src/integrations/prefect-docker/tests/test_containers.py:27:47: error[invalid-argument-type] Argument is incorrect: Expected `str | list[str] | None`, found `str | bool | dict[Unknown | str, Unknown | int] | None`
+ src/integrations/prefect-docker/tests/test_containers.py:27:47: error[invalid-argument-type] Argument is incorrect: Expected `str | None`, found `str | bool | dict[Unknown | str, Unknown | int] | None`
+ src/integrations/prefect-docker/tests/test_containers.py:27:47: error[invalid-argument-type] Argument is incorrect: Expected `bool | None`, found `str | bool | dict[Unknown | str, Unknown | int] | None`
+ src/integrations/prefect-docker/tests/test_containers.py:27:47: error[invalid-argument-type] Argument is incorrect: Expected `str | list[str] | None`, found `str | bool | dict[Unknown | str, Unknown | int] | None`
+ src/integrations/prefect-docker/tests/test_containers.py:27:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, str] | list[str] | None`, found `str | bool | dict[Unknown | str, Unknown | int] | None`
+ src/integrations/prefect-docker/tests/test_containers.py:27:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str | bool | dict[Unknown | str, Unknown | int] | None`
+ src/integrations/prefect-docker/tests/test_containers.py:42:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str`
+ src/integrations/prefect-docker/tests/test_containers.py:55:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str`
+ src/integrations/prefect-docker/tests/test_containers.py:68:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str`
+ src/integrations/prefect-docker/tests/test_containers.py:81:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str`
+ src/integrations/prefect-docker/tests/test_images.py:16:44: error[invalid-argument-type] Argument is incorrect: Expected `str`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:16:44: error[invalid-argument-type] Argument is incorrect: Expected `str | None`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:16:44: error[invalid-argument-type] Argument is incorrect: Expected `str | None`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:16:44: error[invalid-argument-type] Argument is incorrect: Expected `bool`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:16:44: error[invalid-argument-type] Argument is incorrect: Expected `DockerHost | None`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:16:44: error[invalid-argument-type] Argument is incorrect: Expected `DockerRegistryCredentials | None`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:16:44: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:21:16: warning[possibly-missing-attribute] Attribute `id` may be missing on object of type `Unknown | list[Unknown]`
+ src/integrations/prefect-docker/tests/test_images.py:29:47: error[invalid-argument-type] Argument is incorrect: Expected `bool`, found `str`
+ src/integrations/prefect-docker/tests/test_images.py:29:47: error[invalid-argument-type] Argument is incorrect: Expected `DockerRegistryCredentials | None`, found `str`
+ src/integrations/prefect-docker/tests/test_images.py:29:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str`
+ src/integrations/prefect-docker/tests/test_images.py:31:16: warning[possibly-missing-attribute] Attribute `id` may be missing on object of type `Unknown | list[Unknown]`
+ src/integrations/prefect-docker/tests/test_images.py:51:17: error[invalid-argument-type] Argument is incorrect: Expected `bool`, found `str`
+ src/integrations/prefect-docker/tests/test_images.py:51:17: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str`
+ src/integrations/prefect-docker/tests/test_images.py:53:16: warning[possibly-missing-attribute] Attribute `id` may be missing on object of type `Unknown | list[Unknown]`
+ src/integrations/prefect-docker/tests/test_images.py:64:47: error[invalid-argument-type] Argument is incorrect: Expected `str`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:64:47: error[invalid-argument-type] Argument is incorrect: Expected `str | None`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:64:47: error[invalid-argument-type] Argument is incorrect: Expected `str | None`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:64:47: error[invalid-argument-type] Argument is incorrect: Expected `bool`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:64:47: error[invalid-argument-type] Argument is incorrect: Expected `DockerRegistryCredentials | None`, found `str | bool`
+ src/integrations/prefect-docker/tests/test_images.py:64:47: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str | bool`
+ src/integrations/prefect-kubernetes/prefect_kubernetes/jobs.py:429:17: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `str`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:20:13: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `None`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:29:13: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `None`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:38:13: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `None`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:57:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:103:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:149:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:195:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:240:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:286:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_custom_objects.py:344:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_deployments.py:18:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_deployments.py:38:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_deployments.py:70:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_deployments.py:92:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_deployments.py:113:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_deployments.py:141:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_jobs.py:36:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_jobs.py:52:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_jobs.py:68:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_jobs.py:87:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_jobs.py:107:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_jobs.py:131:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_jobs.py:159:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_pods.py:29:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_pods.py:46:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_pods.py:78:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_pods.py:96:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_pods.py:115:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_pods.py:137:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
+ src/integrations/prefect-kubernetes/tests/test_pods.py:167:9: error[invalid-argument-type] Argument is incorrect: Expected `dict[str, Any]`, found `Literal["test"]`
- src/prefect/cache_policies.py:311:25: warning[possibly-missing-attribute] Attribute `__code__` may be missing on object of type `Unknown | (((...) -> Any) & ((*args: object, **kwargs: object) -> object))`
+ src/prefect/cache_policies.py:311:25: warning[possibly-missing-attribute] Attribute `__code__` may be missing on object of type `Unknown | ((...) -> Any)`
- src/prefect/cli/deploy/_core.py:86:21: error[invalid-assignment] Object of type `T@resolve_block_document_references | dict[str, Any]` is not assignable to `dict[str, Any]`
+ src/prefect/cli/deploy/_core.py:86:21: error[invalid-assignment] Object of type `T@resolve_block_document_references | dict[str, Any] | str | ... omitted 4 union elements` is not assignable to `dict[str, Any]`
- src/prefect/cli/deploy/_core.py:87:21: error[invalid-assignment] Object of type `T@resolve_variables` is not assignable to `dict[str, Any]`
+ src/prefect/cli/deploy/_core.py:87:21: error[invalid-assignment] Object of type `T@resolve_variables | str | int | ... omitted 4 union elements` is not assignable to `dict[str, Any]`
- src/prefect/deployments/steps/core.py:137:38: error[invalid-argument-type] Argument is incorrect: Expected `T@resolve_variables`, found `T@resolve_block_document_references | dict[str, Any]`
+ src/prefect/deployments/steps/core.py:137:38: error[invalid-argument-type] Argument is incorrect: Expected `T@resolve_variables`, found `T@resolve_block_document_references | dict[str, Any] | str | ... omitted 4 union elements`
+ src/prefect/task_engine.py:1613:28: error[invalid-await] `Unknown | R@AsyncTaskRunEngine | Coroutine[Any, Any, R@AsyncTaskRunEngine]` is not awaitable
+ src/prefect/task_engine.py:1721:47: error[invalid-argument-type] Argument to function `next` is incorrect: Expected `SupportsNext[Unknown]`, found `Unknown | R@run_generator_task_sync`
+ src/prefect/task_engine.py:1734:25: warning[possibly-missing-attribute] Attribute `throw` may be missing on object of type `Unknown | R@run_generator_task_sync`
+ src/prefect/task_engine.py:1780:48: warning[possibly-missing-attribute] Attribute `__anext__` may be missing on object of type `Unknown | R@run_generator_task_async`
+ src/prefect/task_engine.py:1792:29: warning[possibly-missing-attribute] Attribute `throw` may be missing on object of type `Unknown | R@run_generator_task_async`
- src/prefect/tasks.py:184:9: warning[possibly-missing-attribute] Attribute `__code__` may be missing on object of type `Unknown | (((...) -> Any) & ((*args: object, **kwargs: object) -> object))`
+ src/prefect/tasks.py:184:9: warning[possibly-missing-attribute] Attribute `__code__` may be missing on object of type `Unknown | ((...) -> Any)`
- src/prefect/utilities/templating.py:320:13: error[invalid-assignment] Invalid subscript assignment with key of type `object` and value of type `T@resolve_block_document_references | dict[str, Any]` on object of type `dict[str, Any]`
+ src/prefect/utilities/templating.py:320:13: error[invalid-assignment] Invalid subscript assignment with key of type `object` and value of type `T@resolve_block_document_references | dict[str, Any] | str | ... omitted 4 union elements` on object of type `dict[str, Any]`
- src/prefect/utilities/templating.py:323:16: error[invalid-return-type] Return type does not match returned value: expected `T@resolve_block_document_references | dict[str, Any]`, found `list[T@resolve_block_document_references | dict[str, Any] | Unknown]`
+ src/prefect/utilities/templating.py:323:16: error[invalid-return-type] Return type does not match returned value: expected `T@resolve_block_document_references | dict[str, Any]`, found `list[T@resolve_block_document_references | dict[str, Any] | str | ... omitted 5 union elements]`
- src/prefect/utilities/templating.py:437:16: error[invalid-return-type] Return type does not match returned value: expected `T@resolve_variables`, found `dict[object, T@resolve_variables | Unknown]`
+ src/prefect/utilities/templating.py:437:16: error[invalid-return-type] Return type does not match returned value: expected `T@resolve_variables`, found `dict[object, T@resolve_variables | str | int | ... omitted 5 union elements]`
- src/prefect/utilities/templating.py:442:16: error[invalid-return-type] Return type does not match returned value: expected `T@resolve_variables`, found `list[T@resolve_variables | Unknown]`
+ src/prefect/utilities/templating.py:442:16: error[invalid-return-type] Return type does not match returned value: expected `T@resolve_variables`, found `list[T@resolve_variables | str | int | ... omitted 5 union elements]`
- src/prefect/workers/base.py:232:13: error[invalid-argument-type] Argument is incorrect: Expected `T@resolve_variables`, found `T@resolve_block_document_references | dict[str, Any]`
+ src/prefect/workers/base.py:232:13: error[invalid-argument-type] Argument is incorrect: Expected `T@resolve_variables`, found `T@resolve_block_document_references | dict[str, Any] | str | ... omitted 4 union elements`
- src/prefect/workers/base.py:234:20: error[invalid-argument-type] Argument expression after ** must be a mapping type: Found `T@resolve_variables`
+ src/prefect/workers/base.py:234:20: error[invalid-argument-type] Argument expression after ** must be a mapping type: Found `T@resolve_variables | str | int | ... omitted 4 union elements`
- Found 5291 diagnostics
+ Found 5365 diagnostics

pandas (https://github.com/pandas-dev/pandas)
- pandas/tests/scalar/test_na_scalar.py:158:12: error[unsupported-operator] Unary operator `-` is not supported for object of type `NAType`
- pandas/tests/scalar/test_na_scalar.py:159:16: error[invalid-argument-type] Argument to function `abs` is incorrect: Expected `SupportsAbs[Unknown]`, found `NAType`
- pandas/tests/scalar/test_na_scalar.py:160:12: error[unsupported-operator] Unary operator `~` is not supported for object of type `NAType`
- pandas/tests/scalar/test_na_scalar.py:165:12: error[unsupported-operator] Operator `&` is not supported between objects of type `Literal[True]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:166:12: error[unsupported-operator] Operator `&` is not supported between objects of type `NAType` and `Literal[False]`
- pandas/tests/scalar/test_na_scalar.py:167:12: error[unsupported-operator] Operator `&` is not supported between objects of type `Literal[False]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:168:12: error[unsupported-operator] Operator `&` is not supported between two objects of type `NAType`
- pandas/tests/scalar/test_na_scalar.py:171:12: error[unsupported-operator] Operator `&` is not supported between objects of type `NAType` and `numpy.bool[builtins.bool]`
- pandas/tests/scalar/test_na_scalar.py:172:12: error[unsupported-operator] Operator `&` is not supported between objects of type `numpy.bool[builtins.bool]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:173:12: error[unsupported-operator] Operator `&` is not supported between objects of type `NAType` and `numpy.bool[builtins.bool]`
- pandas/tests/scalar/test_na_scalar.py:174:12: error[unsupported-operator] Operator `&` is not supported between objects of type `numpy.bool[builtins.bool]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:178:9: error[unsupported-operator] Operator `&` is not supported between objects of type `NAType` and `Literal[5]`
- pandas/tests/scalar/test_na_scalar.py:185:12: error[unsupported-operator] Operator `|` is not supported between objects of type `Literal[False]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:186:12: error[unsupported-operator] Operator `|` is not supported between two objects of type `NAType`
- pandas/tests/scalar/test_na_scalar.py:189:12: error[unsupported-operator] Operator `|` is not supported between objects of type `NAType` and `numpy.bool[builtins.bool]`
- pandas/tests/scalar/test_na_scalar.py:190:12: error[unsupported-operator] Operator `|` is not supported between objects of type `numpy.bool[builtins.bool]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:191:12: error[unsupported-operator] Operator `|` is not supported between objects of type `NAType` and `numpy.bool[builtins.bool]`
- pandas/tests/scalar/test_na_scalar.py:192:12: error[unsupported-operator] Operator `|` is not supported between objects of type `numpy.bool[builtins.bool]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:196:9: error[unsupported-operator] Operator `|` is not supported between objects of type `NAType` and `Literal[5]`
- pandas/tests/scalar/test_na_scalar.py:201:12: error[unsupported-operator] Operator `^` is not supported between objects of type `Literal[True]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:202:12: error[unsupported-operator] Operator `^` is not supported between objects of type `NAType` and `Literal[False]`
- pandas/tests/scalar/test_na_scalar.py:203:12: error[unsupported-operator] Operator `^` is not supported between objects of type `Literal[False]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:204:12: error[unsupported-operator] Operator `^` is not supported between two objects of type `NAType`
- pandas/tests/scalar/test_na_scalar.py:207:12: error[unsupported-operator] Operator `^` is not supported between objects of type `NAType` and `numpy.bool[builtins.bool]`
- pandas/tests/scalar/test_na_scalar.py:208:12: error[unsupported-operator] Operator `^` is not supported between objects of type `numpy.bool[builtins.bool]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:209:12: error[unsupported-operator] Operator `^` is not supported between objects of type `NAType` and `numpy.bool[builtins.bool]`
- pandas/tests/scalar/test_na_scalar.py:210:12: error[unsupported-operator] Operator `^` is not supported between objects of type `numpy.bool[builtins.bool]` and `NAType`
- pandas/tests/scalar/test_na_scalar.py:214:9: error[unsupported-operator] Operator `^` is not supported between objects of type `NAType` and `Literal[5]`
- pandas/tests/scalar/timedelta/test_arithmetic.py:627:25: error[unsupported-operator] Operator `//` is not supported between objects of type `Timedelta` and `NaTType`
- Found 3794 diagnostics
+ Found 3765 diagnostics

scikit-build-core (https://github.com/scikit-build/scikit-build-core)
+ src/scikit_build_core/build/wheel.py:99:20: error[no-matching-overload] No overload of bound method `__init__` matches arguments
- Found 47 diagnostics
+ Found 48 diagnostics

static-frame (https://github.com/static-frame/static-frame)
- static_frame/core/node_selector.py:526:16: error[invalid-return-type] Return type does not match returned value: expected `InterGetItemLocReduces[TVContainer_co@InterfaceSelectQuartet, Any]`, found `InterGetItemLocReduces[Bottom[Series[Any, Any]] | Unknown, Any]`
+ static_frame/core/node_selector.py:526:16: error[invalid-return-type] Return type does not match returned value: expected `InterGetItemLocReduces[TVContainer_co@InterfaceSelectQuartet, Any]`, found `InterGetItemLocReduces[Unknown | Bottom[Series[Any, Any]], Any]`
- static_frame/core/series.py:772:16: error[invalid-return-type] Return type does not match returned value: expected `InterGetItemILocReduces[Series[Any, Any], TVDtype@Series]`, found `InterGetItemILocReduces[Series[Any, Any] | ndarray[Never, Never] | TypeBlocks | ... omitted 6 union elements, TVDtype@Series]`
+ static_frame/core/series.py:772:16: error[invalid-return-type] Return type does not match returned value: expected `InterGetItemILocReduces[Series[Any, Any], TVDtype@Series]`, found `InterGetItemILocReduces[Series[Any, Any] | Bottom[Index[Any]] | TypeBlocks | ... omitted 6 union elements, TVDtype@Series]`
+ static_frame/core/series.py:4072:16: error[invalid-return-type] Return type does not match returned value: expected `InterGetItemILocReduces[SeriesHE[Any, Any], TVDtype@SeriesHE]`, found `InterGetItemILocReduces[Bottom[Series[Any, Any]] | Bottom[Index[Any]] | TypeBlocks | ... omitted 7 union elements, TVDtype@SeriesHE]`
- static_frame/core/yarn.py:418:16: error[invalid-return-type] Return type does not match returned value: expected `InterGetItemILocReduces[Yarn[Any], object_]`, found `InterGetItemILocReduces[Yarn[Any] | Bottom[Index[Any]] | TypeBlocks | ... omitted 6 union elements, object_]`
+ static_frame/core/yarn.py:418:16: error[invalid-return-type] Return type does not match returned value: expected `InterGetItemILocReduces[Yarn[Any], object_]`, found `InterGetItemILocReduces[Yarn[Any] | ndarray[Never, Never] | TypeBlocks | ... omitted 6 union elements, object_]`
- Found 1826 diagnostics
+ Found 1827 diagnostics

rotki (https://github.com/rotki/rotki)
- rotkehlchen/chain/decoding/tools.py:96:44: warning[unused-ignore-comment] Unused blanket `type: ignore` directive
- rotkehlchen/chain/decoding/tools.py:99:13: error[invalid-argument-type] Argument to function `decode_transfer_direction` is incorrect: Expected `Sequence[A@BaseDecoderTools]`, found `Unknown | tuple[BTCAddress, ...] | tuple[ChecksumAddress, ...] | tuple[SubstrateAddress, ...] | tuple[SolanaAddress, ...]`
- rotkehlchen/chain/decoding/tools.py:100:62: warning[unused-ignore-comment] Unused blanket `type: ignore` directive
+ rotkehlchen/chain/decoding/tools.py:97:13: error[invalid-argument-type] Argument to function `decode_transfer_direction` is incorrect: Expected `BTCAddress | ChecksumAddress | SubstrateAddress | SolanaAddress`, found `A@BaseDecoderTools`
+ rotkehlchen/chain/decoding/tools.py:98:13: error[invalid-argument-type] Argument to function `decode_transfer_direction` is incorrect: Expected `BTCAddress | ChecksumAddress | SubstrateAddress | SolanaAddress | None`, found `A@BaseDecoderTools | None`
- Found 2057 diagnostics
+ Found 2056 diagnostics

No memory usage changes detected ✅

astral-sh-bot · 2026-01-12T08:28:25Z

`ecosystem-analyzer` results

Lint rule	Removed	Changed
`unsupported-operator`	28	0
`invalid-return-type`	1	5
`invalid-argument-type`	1	0
Total	30	5

Full report with detailed diff (timing results)

AlexWaygood

Thanks, this is great!!

crates/ty_python_semantic/src/types/narrow.rs

…AlexWaygood

AlexWaygood

Thanks!

drbh added 2 commits January 11, 2026 18:38

feat: narrow right comparison op

448a317

feat: update eq doc tests

8ef0abb

drbh requested review from AlexWaygood, carljm, dcreager and sharkdp as code owners January 11, 2026 23:56

AlexWaygood added the ty Multi-file analysis & type inference label Jan 11, 2026

fix: update conditional docs too

4a6a48b

MichaReiser added the ecosystem-analyzer label Jan 12, 2026

AlexWaygood reviewed Jan 12, 2026

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crates/ty_python_semantic/src/types/narrow.rs Outdated Show resolved Hide resolved

drbh and others added 3 commits January 12, 2026 11:57

fix: move logic after call expr to avoid the extra check. patch from …

8b7b0a7

…AlexWaygood

fix: cleanup comment and add tests

0c42a5c

make test an mdtest

d63ae16

AlexWaygood approved these changes Jan 13, 2026

View reviewed changes

AlexWaygood changed the title ~~[ty] narrow right comparison op~~ [ty] narrow the right-hand side of ==, !=, is and is not conditions when the left-hand side is not narrowable Jan 13, 2026

AlexWaygood enabled auto-merge (squash) January 13, 2026 15:57

AlexWaygood merged commit d13b5db into astral-sh:main Jan 13, 2026
44 checks passed

AlexWaygood mentioned this pull request Jan 15, 2026

[ty] Right-hand side narrowing for if Foo is type(x) expressions #22608

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[ty] narrow the right-hand side of `==`, `!=`, `is` and `is not` conditions when the left-hand side is not narrowable#22511

[ty] narrow the right-hand side of `==`, `!=`, `is` and `is not` conditions when the left-hand side is not narrowable#22511
AlexWaygood merged 6 commits intoastral-sh:mainfrom
drbh:narrow-right-comparison-op

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drbh commented Jan 11, 2026

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