# Copyright 2021 The HuggingFace Team. All rights reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # This file can carry repo-local rule overrides for faster iteration between # `transformers-mlinter` releases. # Keep it synced with the upstream package's rules.toml when possible so local # behavior does not drift from the published checker longer than necessary. version = 1 [rules.TRF001] description = "Class-level config_class on PreTrainedModel should match Config naming." default_enabled = true allowlist_models = ["qwen3_omni_moe"] [rules.TRF001.explanation] what_it_does = "Checks naming consistency between PreTrainedModel and config_class." why_bad = "Mismatched config_class can break loading, auto classes, and developer expectations." diff = ''' class AcmePreTrainedModel(PreTrainedModel): - config_class = WileConfig + config_class = AcmeConfig ''' [rules.TRF002] description = "base_model_prefix should be a non-empty canonical string when defined on PreTrainedModel classes." default_enabled = true allowlist_models = ["lighton_ocr"] [rules.TRF002.explanation] what_it_does = "Checks that base_model_prefix, when set, is a non-empty, whitespace-free string literal." why_bad = "Invalid prefixes can break weight loading key mapping and base model access patterns." diff = ''' class AcmePreTrainedModel(PreTrainedModel): - base_model_prefix = "" + base_model_prefix = "model" ''' [rules.TRF003] description = "forward() should use capture_output/can_return_tuple decorators instead of manual return_dict branching." default_enabled = false allowlist_models = [] [rules.TRF003.explanation] what_it_does = "Detects forward methods that use the old 'if not return_dict: return (x,)' pattern." why_bad = "The old return_dict branching pattern is error-prone and verbose. Use the capture_output or can_return_tuple decorators instead." diff = ''' -def forward(self, x, return_dict=None): - if not return_dict: - return (x,) - return AcmeModelOutput(last_hidden_state=x) +@can_return_tuple +def forward(self, x): + return AcmeModelOutput(last_hidden_state=x) ''' [rules.TRF004] description = "Models must never override tie_weights. Use _tied_weights_keys instead." default_enabled = true allowlist_models = ["data2vec", "hubert", "sew", "sew_d", "unispeech", "unispeech_sat", "wav2vec2", "wav2vec2_conformer", "wavlm"] [rules.TRF004.explanation] what_it_does = "Checks that no model class defines a tie_weights method." why_bad = "Overriding tie_weights leads to bad consequences for loading, device_map computation, and saving. Use _tied_weights_keys class attribute to declare tied weights instead." diff = ''' -def tie_weights(self): - self.lm_head.weight = self.emb.weight +class AcmeForCausalLM(AcmePreTrainedModel): + _tied_weights_keys = ["lm_head.weight"] ''' [rules.TRF005] description = "_no_split_modules, when defined, should be a list/tuple of non-empty strings." default_enabled = true allowlist_models = ["d_fine", "deformable_detr", "glm46v", "lw_detr", "pp_doclayout_v3", "rt_detr", "rt_detr_v2", "voxtral", "voxtral_realtime"] [rules.TRF005.explanation] what_it_does = "Checks the shape of _no_split_modules when present." why_bad = "Malformed values can break device-map partitioning and sharding behavior." diff = ''' -_no_split_modules = [SomeLayerClass, ""] +_no_split_modules = ["AcmeDecoderLayer", "AcmeAttention"] ''' [rules.TRF006] description = "forward with cache arguments should reference cache control/state variables consistently." default_enabled = true allowlist_models = ["chinese_clip", "evolla", "idefics2", "llama4"] [rules.TRF006.explanation] what_it_does = "Checks forward signatures that expose cache arguments for usage of those arguments in method body." why_bad = "Unused cache arguments can indicate incomplete caching support and inconsistent API behavior." diff = ''' def forward(self, x, past_key_values=None, use_cache=False): + if use_cache: + ... return x ''' [rules.TRF007] description = "self.post_init() in __init__ should remain at the end of initialization for PreTrainedModel classes." default_enabled = true allowlist_models = ["distilbert", "lxmert", "mt5", "pix2struct", "pop2piano", "switch_transformers", "t5"] [rules.TRF007.explanation] what_it_does = "Checks for self attribute assignments after self.post_init() in __init__." why_bad = "Mutating model structure after post_init can bypass intended initialization/finalization logic." diff = ''' def __init__(self, config): ... - self.post_init() - self.proj = nn.Linear(...) + self.proj = nn.Linear(...) + self.post_init() ''' [rules.TRF008] description = "Doc decorators on PreTrainedModel classes should avoid empty add_start_docstrings usage." default_enabled = true [rules.TRF008.explanation] what_it_does = "Checks add_start_docstrings usage on model classes for non-empty docstring arguments." why_bad = "Empty decorator usage produces unclear docs and weakens generated API documentation quality." diff = ''' -@add_start_docstrings("") +@add_start_docstrings("The Acme model.") class AcmeModel(AcmePreTrainedModel): ... ''' [rules.TRF009] description = "modeling_.py should avoid importing implementation code from another model package." default_enabled = true allowlist_models = ["dpr", "maskformer", "sam3_video", "vision_text_dual_encoder"] [rules.TRF009.explanation] what_it_does = "Checks modeling files for cross-model imports such as transformers.models.other_model.* or from ..other_model.* imports." why_bad = "Cross-model implementation imports violate the single-file policy and make model behavior harder to inspect and maintain." diff = ''' -from transformers.models.llama.modeling_llama import LlamaAttention +# Keep implementation local to this file. +# If reusing code, copy it with a # Copied from comment. ''' [rules.TRF010] description = "Direct config definitions must use @strict(accept_kwargs=True)." default_enabled = true allowlist_models = ["nemotron_h", "vibevoice_asr"] [rules.TRF010.explanation] what_it_does = "Checks direct PreTrainedConfig/PretrainedConfig subclasses in configuration_*.py and modular_*.py for an explicit @strict(accept_kwargs=True) decorator." why_bad = "Without strict, new config classes miss the repo's runtime type-validation contract and drift from the dataclass-based config standard." diff = ''' +@strict(accept_kwargs=True) class AcmeConfig(PreTrainedConfig): ... ''' [rules.TRF011] description = "forward() must not access non-nn.Module attributes on submodules (breaks pipeline parallelism with Identity replacement)." default_enabled = true allowlist_models = [] [rules.TRF011.explanation] what_it_does = "In forward() methods of PreTrainedModel subclasses, checks for attribute accesses on submodules that would not exist on torch.nn.Identity. This includes attribute accesses on loop variables iterating over self.layers, and self.. chains where is not a standard nn.Module attribute." why_bad = "Pipeline parallelism may replace any submodule with torch.nn.Identity. Accessing custom attributes (e.g. decoder_layer.attention_type) on a replaced module raises AttributeError at runtime. Per-layer metadata should be read from self.config instead." diff = ''' def forward(self, ...): - for decoder_layer in self.layers: + for i, decoder_layer in enumerate(self.layers): hidden_states = decoder_layer( hidden_states, - attention_mask=causal_mask_mapping[decoder_layer.attention_type], + attention_mask=causal_mask_mapping[self.config.layer_types[i]], ) ''' [rules.TRF012] description = "_init_weights must use init primitives, not in-place operations on module weights." default_enabled = true allowlist_models = [] [rules.TRF012.explanation] what_it_does = "Checks that _init_weights(self, module) does not use in-place operations (e.g. .normal_(), .zero_()) directly on module weights." why_bad = "We rely on internal flags set on parameters to track whether they need re-initialization. In-place ops bypass this mechanism. Use the `init` primitives instead." diff = ''' +from transformers import initialization as init + def _init_weights(self, module): - module.weight.normal_(mean=0.0, std=0.02) + init.normal_(module.weight, mean=0.0, std=0.02) ''' [rules.TRF013] description = "PreTrainedModel __init__ must call self.post_init()." default_enabled = true allowlist_models = [] [rules.TRF013.explanation] what_it_does = "Checks that every PreTrainedModel subclass with an __init__ method calls self.post_init(). In modular files, calling super().__init__() is also accepted since it propagates post_init from the parent." why_bad = "post_init performs essential finalization (weight initialization, gradient checkpointing setup, etc.). Omitting it causes subtle runtime bugs." diff = ''' class AcmeModel(AcmePreTrainedModel): def __init__(self, config): super().__init__(config) self.layers = nn.ModuleList(...) + self.post_init() ''' [rules.TRF014] description = "`trust_remote_code` should never be used in native model integrations." default_enabled = true # The `auto` package is the loader layer that *implements* the `trust_remote_code` # feature, forwarding the user-supplied flag to `*.from_pretrained`. It is not a native # model integration, so it is exempt from this rule. allowlist_models = ["auto"] [rules.TRF014.explanation] what_it_does = "Checks whether `trust_remote_code` is passed or used in code (e.g. as kwarg) within native model integration files." why_bad = "`trust_remote_code` allows arbitrary loading, including binaries, which should only be a power feature for users, not a standard use-case. Native integrations must not depend on it, as remote code cannot be reviewed or maintained within transformers." diff = ''' class AcmeModel(AcmePreTrainedModel): def __init__(self, config): super().__init__(config) - self.model = AutoModel.from_pretrained(..., trust_remote_code=True) + self.model = AutoModel.from_pretrained(...) ''' [rules.TRF015] description = "Models with non-empty _tied_weights_keys must have tie_word_embeddings in their Config." default_enabled = true allowlist_models = [] [rules.TRF015.explanation] what_it_does = "When a PreTrainedModel subclass defines _tied_weights_keys as a non-empty collection, checks that the corresponding configuration file declares a tie_word_embeddings field." why_bad = "Without tie_word_embeddings in the config, users cannot control weight tying behavior. The model ties weights unconditionally, breaking serialization round-trips and preventing fine-tuning with untied heads." diff = ''' # configuration_foo.py @strict(accept_kwargs=True) class FooConfig(PreTrainedConfig): hidden_size: int = 768 + tie_word_embeddings: bool = True ''' [rules.TRF016] description = "do_* flags declared on a processor class must be referenced by overridden preprocess/_preprocess." default_enabled = true allowlist_models = ["kimi_k25", "minimax_m3_vl"] [rules.TRF016.explanation] what_it_does = "When an image_processing_*.py or video_processing_*.py class declares boolean do_* attributes (e.g. do_resize, do_rescale, do_normalize, do_convert_rgb) and overrides preprocess() or _preprocess(), checks that each declared flag is still consumed along the override path. That can be a direct reference in the override body, delegating back to the base implementation via super().preprocess(..., **kwargs) or super()._preprocess(..., **kwargs), or, for image processors, forwarding do_convert_rgb into the shared image-preparation path via _preprocess_image_like_inputs(...) or _prepare_image_like_inputs(...). The allowlist of base-handled flags (do_sample_frames) is exempted because the base preprocess() consumes them before _preprocess() runs." why_bad = "A do_X attribute that is not referenced by the override is a dead flag: setting do_X=False at construction or call time has no effect, and the underlying operation runs unconditionally. This silently breaks user expectations and makes per-call overrides ineffective." diff = ''' class AcmeVideoProcessor(BaseVideoProcessor): do_resize = True do_normalize = True def _preprocess( self, videos, + do_resize: bool, + do_normalize: bool, size, image_mean, image_std, **kwargs, ): for video in videos: - video = self.resize(video, size=size) - video = self.normalize(video, image_mean, image_std) + if do_resize: + video = self.resize(video, size=size) + if do_normalize: + video = self.normalize(video, image_mean, image_std) ''' [rules.TRF017] description = "@auto_docstring must be placed above @dataclass on output classes." default_enabled = true allowlist_models = [] [rules.TRF017.explanation] what_it_does = "Checks classes decorated with both @auto_docstring and @dataclass for source ordering: @auto_docstring must appear above @dataclass." why_bad = "Decorators are applied bottom-up. When @dataclass is listed above @auto_docstring, @auto_docstring runs first on a class that has no synthesized __init__ yet and ends up modifying the parent class's __init__.__doc__ instead of the subclass's." diff = ''' -@dataclass @auto_docstring( custom_intro=""" Output type of [`AcmeForPreTraining`]. """ ) +@dataclass class AcmeForPreTrainingOutput(ModelOutput): ... ''' [rules.TRF018] description = "_init_weights overrides should call super()._init_weights(module), except modular-file sentinels." default_enabled = true allowlist_models = ["cosmos3_omni", "diffusion_gemma", "eomt_dinov3", "exaone4_5", "gemma4", "higgs_audio_v2", "kimi_k25", "olmo3", "pp_formulanet", "pp_lcnet_v3", "radio", "sam3_lite_text", "sam3_tracker", "slanet", "voxtral_realtime", "xcodec2"] [rules.TRF018.explanation] what_it_does = "Checks that every PreTrainedModel subclass that overrides `_init_weights(self, module, ...)` chains the call up via `super()._init_weights(...)`. In modular files, `PreTrainedModel._init_weights(self, module)` and `raise AttributeError(...)` are accepted because they are modularization sentinels. If a model intentionally fully overrides initialization, suppress with `# trf-ignore: TRF018` on the line above the method." why_bad = "The base `_init_weights` covers standard module types (Linear, Embedding, LayerNorm, RotaryEmbedding, ...). Skipping `super()._init_weights(...)` silently leaves submodules unhandled by the override uninitialized, which can pass tests and surface much later as subtle weight-init bugs (cf. https://github.com/huggingface/transformers/pull/45597)." diff = ''' from ... import initialization as init def _init_weights(self, module): + super()._init_weights(module) if isinstance(module, AcmeCustomLayer): - module.gate.data.zero_() + init.zeros_(module.gate) ''' [rules.TRF019] description = "A processor TypedDict class must not define `_defaults`, instead push them upstream to the hub (`processor_config.json`)." default_enabled = true allowlist_models = ["blip_2", "grounding_dino", "hunyuan_vl", "kosmos2", "omdet_turbo", "qwen3_asr"] cutoff_date = "2026-06-20" [rules.TRF019.explanation] what_it_does = "Checks that `*ProcessorKwargs` TypedDict classes in `processing_*.py` files do not set a non-empty `_defaults` dict. Old models released before cutoff date are not checked against the rule for backwards compatibility; new models must not hardcode defaults in Python." why_bad = "Hardcoding defaults in `_defaults` scatters processor configuration across Python source files, makes it unintuitive when it comes to overriding defaults via config, and bloats up the code. The canonical home for processor defaults is `processor_config.json` on the hub, which is shipped with the checkpoint and can be updated without touching code." diff = ''' class Gemma4ProcessorKwargs(ProcessingKwargs, total=False): - _defaults = { - "text_kwargs": {"padding": False}, - "images_kwargs": {"return_tensors": "pt"}, - } images_kwargs: Gemma4ImageProcessorKwargs '''