[CI] Fix mypy for vllm/engine and vllm/utils

[wwl2755]

Part of #26533

Fix mypy precommit issues under "vllm/engine" and "vllm/utils" and move them to "FILES"

CC: @hmellor @yewentao256

Original:

Run mypy for local Python installation..............................................................Failed
- hook id: mypy-local
- exit code: 1

$ mypy --python-version 3.12 --follow-imports skip 
vllm/transformers_utils/tokenizers/mistral.py:354: error: Argument 1 to "encode_one" of "MistralTokenizer" has incompatible type "str | int"; expected "str"  [arg-type]
vllm/transformers_utils/tokenizers/mistral.py:359: error: Incompatible types in assignment (expression has type "str | list[str] | list[int]", variable has type "list[int] | list[list[int]]")  [assignment]
vllm/transformers_utils/tokenizers/mistral.py:362: error: Argument 1 to "encode_one" of "MistralTokenizer" has incompatible type "str | list[str] | list[int]"; expected "str"  [arg-type]
vllm/multimodal/parse.py:369: error: Value of type "object" is not indexable  [index]
vllm/multimodal/parse.py:437: error: Incompatible types in assignment (expression has type "list[float] | Any | list[list[float] | Any | Any | tuple[Any, float] | Any | None]", variable has type "list[list[float] | Any | tuple[Any, float] | list[list[float] | Any | Any | tuple[Any, float] | Any | None]]")  [assignment]
vllm/multimodal/parse.py:501: error: Incompatible types in assignment (expression has type "list[Any] | Any | list[list[Any] | Any | Any | Any | tuple[list[Any] | Any | Any, dict[str, Any]] | None] | tuple[Any, ...]", variable has type "list[list[Any] | Any | tuple[list[Any] | Any | Any, dict[str, Any]] | list[list[Any] | Any | Any | Any | tuple[list[Any] | Any | Any, dict[str, Any]] | None]]")  [assignment]
vllm/engine/arg_utils.py:1246: error: Argument "tokenizer" to "maybe_override_with_speculators" has incompatible type "str | None"; expected "str"  [arg-type]
vllm/engine/arg_utils.py:1271: error: Argument 1 to "_set_default_args" of "EngineArgs" has incompatible type "UsageContext | None"; expected "UsageContext"  [arg-type]
Found 8 errors in 3 files (checked 164 source files)

$ mypy --python-version 3.12 --follow-imports skip 
vllm/utils/jsontree.py:97: error: Incompatible return value type (got "list[_U | dict[str, _U]]", expected "BatchedTensorInputs | _JSONTree[_U]")  [return-value]
vllm/utils/jsontree.py:148: error: Type variable "vllm.utils.jsontree._U" is unbound  [valid-type]
vllm/utils/jsontree.py:148: note: (Hint: Use "Generic[_U]" or "Protocol[_U]" base class to bind "_U" inside a class)
vllm/utils/jsontree.py:148: note: (Hint: Use "_U" in function signature to bind "_U" inside a function)
vllm/utils/jsontree.py:157: error: Incompatible return value type (got "object", expected "_T | _U")  [return-value]
vllm/utils/jsontree.py:157: note: Error code "return-value" not covered by "type: ignore" comment
vllm/utils/__init__.py:489: error: Need type annotation for "awaits"  [var-annotated]
vllm/utils/__init__.py:489: error: Argument 1 to "create_task" of "AbstractEventLoop" has incompatible type "Awaitable[T]"; expected "Coroutine[Any, Any, Never]"  [arg-type]
vllm/utils/__init__.py:498: error: Argument 1 to "anext" has incompatible type "AsyncGenerator[Any, None]"; expected "_SupportsSynchronousAnext[Coroutine[Any, Any, Any]]"  [arg-type]
vllm/utils/__init__.py:1167: error: Item "None" of "list[str] | None" has no attribute "__iter__" (not iterable)  [union-attr]


$ mypy --python-version 3.12 
vllm/engine/arg_utils.py:218: error: Too few arguments  [call-arg]
vllm/engine/arg_utils.py:351: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "list[int]")  [assignment]
vllm/engine/arg_utils.py:377: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "EPLBConfig")  [assignment]
vllm/engine/arg_utils.py:412: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "dict[str, Any]")  [assignment]
vllm/engine/arg_utils.py:415: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "dict[str, Any] | Callable[[Any], Any]")  [assignment]
vllm/engine/arg_utils.py:420: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "dict[str, int | dict[str, int]]")  [assignment]
vllm/engine/arg_utils.py:424: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "dict[str, dict[str, Any]]")  [assignment]
vllm/engine/arg_utils.py:439: error: Incompatible types in assignment (expression has type "float | None", variable has type "float")  [assignment]
vllm/engine/arg_utils.py:454: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "dict[Any, Any]")  [assignment]
vllm/engine/arg_utils.py:455: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "str | list[str]")  [assignment]
vllm/engine/arg_utils.py:464: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "StructuredOutputsConfig")  [assignment]
vllm/engine/arg_utils.py:492: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "CompilationConfig")  [assignment]
vllm/engine/arg_utils.py:501: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "dict[str, Any]")  [assignment]
vllm/engine/arg_utils.py:505: error: Incompatible types in assignment (expression has type "str | None", variable has type "str")  [assignment]
vllm/engine/arg_utils.py:511: error: Incompatible types in assignment (expression has type "Field[Any]", variable has type "dict[str, Any]")  [assignment]
vllm/engine/arg_utils.py:514: error: Incompatible types in assignment (expression has type "str | dict[str, str]", variable has type "str")  [assignment]
vllm/engine/arg_utils.py:1104: error: Argument "tokenizer" to "ModelConfig" has incompatible type "str | None"; expected "str"  [arg-type]
vllm/engine/arg_utils.py:1118: error: Argument "max_model_len" to "ModelConfig" has incompatible type "int | None"; expected "int"  [arg-type]
vllm/engine/arg_utils.py:1307: error: Argument "block_size" to "CacheConfig" has incompatible type "Literal[1, 8, 16, 32, 64, 128] | None"; expected "Literal[1, 8, 16, 32, 64, 128]"  [arg-type]
vllm/engine/arg_utils.py:1455: error: Argument "data_parallel_backend" to "ParallelConfig" has incompatible type "str"; expected "Literal['ray', 'mp']"  [arg-type]
vllm/engine/arg_utils.py:1493: error: Argument "max_num_batched_tokens" to "SchedulerConfig" has incompatible type "int | None"; expected "int"  [arg-type]
vllm/engine/arg_utils.py:1494: error: Argument "max_num_seqs" to "SchedulerConfig" has incompatible type "int | None"; expected "int"  [arg-type]
vllm/engine/arg_utils.py:1521: error: Argument "max_lora_rank" to "LoRAConfig" has incompatible type "int"; expected "Literal[1, 8, 16, 32, 64, 128, 256, 320, 512]"  [arg-type]
vllm/engine/arg_utils.py:1525: error: Argument "lora_extra_vocab_size" to "LoRAConfig" has incompatible type "int"; expected "Literal[256, 512]"  [arg-type]
vllm/engine/arg_utils.py:1548: error: "StructuredOutputsConfig" has no attribute "guided_decoding_backend"  [attr-defined]
vllm/engine/arg_utils.py:1550: error: "StructuredOutputsConfig" has no attribute "guided_decoding_disable_fallback"  [attr-defined]
vllm/engine/arg_utils.py:1554: error: "StructuredOutputsConfig" has no attribute "guided_decoding_disable_any_whitespace"  [attr-defined]
vllm/engine/arg_utils.py:1558: error: "StructuredOutputsConfig" has no attribute "guided_decoding_disable_additional_properties"; maybe "disable_additional_properties"?  [attr-defined]
vllm/engine/arg_utils.py:1602: error: Argument "feature_name" to "_raise_or_fallback" has incompatible type "list[str]"; expected "str"  [arg-type]
vllm/engine/arg_utils.py:1718: error: Item "None" of "PoolerConfig | None" has no attribute "pooling_type"  [union-attr]
vllm/engine/metrics.py:54: error: Item "None" of "ObservabilityConfig | None" has no attribute "show_hidden_metrics"  [union-attr]
Found 31 errors in 2 files (checked 171 source files)

[gemini-code-assist]

Code Review

This pull request focuses on fixing mypy pre-commit issues to enable stricter type checking for the vllm/engine module. The changes primarily involve adding explicit type casts, updating type hints, and using type: ignore to resolve type errors reported by mypy. The fixes are generally correct and achieve the goal of making the code mypy-compliant. However, I've identified two instances in vllm/multimodal/parse.py where using # type: ignore hides a potential runtime error. In these cases, the code does not handle None values that can appear in a list of multimodal data, which could lead to exceptions. I've suggested a more robust fix that handles these None values gracefully while also resolving the type error.

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @wwl2755.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[yewentao256]

Please also fix the pre-commit issue and merge from main, so that we can get this landed

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @wwl2755.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[DarkLight1337]

Are these changes to block size intentional?

[wwl2755]

I think so. To satisfy the type validation, block size has to be one of [1, 8, 16, 32, 64, 128] cc: @hmellor

[DarkLight1337]

cc @heheda12345 @tlrmchlsmth is it ok to change these tests to use the correct block sizes?

[hmellor]

Before, we were not validating the block size but we did specify a list of valid block sizes. We should either update the test or update the possible valid block sizes

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @wwl2755.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[yewentao256]

Please take a look at the CI issue, try if we can reproduce it locally

[wwl2755]

Thanks! I can reproduce it offline. It seems using pydantic.Field leads to more validation errors in the tests. And simpliy SkipValidation seems not solve all problems.

[hmellor]

I'll take a look at the failures too

[hmellor]

Looks like I fixed this locally and forgot to push... One moment

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @wwl2755.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[yewentao256]

Please fix the pre-commit and conflicts so that we can land this PR

[hmellor]

superseded by #29674