Remove deprecated trainer_optimizer_mixin (#14887)

Co-authored-by: Rohit Gupta <rohitgr1998@gmail.com>
Co-authored-by: Adrian Wälchli <aedu.waelchli@gmail.com>

src/pytorch_lightning/CHANGELOG.md

@@ -222,7 +222,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Removed the deprecated `Trainer.use_amp` and `LightningModule.use_amp` attributes ([#14832](https://github.com/Lightning-AI/lightning/pull/14832))
 
 
-- Removed the deprecated `Trainer.run_stage` in favor of `Trainer.{fit,validate,test,predict}`
+- Removed the deprecated `Trainer.run_stage` in favor of `Trainer.{fit,validate,test,predict}` ([#14870](https://github.com/Lightning-AI/lightning/pull/14870))
 
 
 - Removed the deprecated `SimpleProfiler.profile_iterable` and `AdvancedProfiler.profile_iterable` attributes ([#14864](https://github.com/Lightning-AI/lightning/pull/14864))
@@ -231,7 +231,11 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Removed the deprecated `Trainer.verbose_evaluate` ([#14884](https://github.com/Lightning-AI/lightning/pull/14884))
 
 
-- Remove the deprecated `Trainer.should_rank_save_checkpoint` ([#14885](https://github.com/Lightning-AI/lightning/pull/14885))
+- Removed the deprecated `Trainer.should_rank_save_checkpoint` ([#14885](https://github.com/Lightning-AI/lightning/pull/14885))
+
+
+- Removed the deprecated `TrainerOptimizersMixin` ([#14887](https://github.com/Lightning-AI/lightning/pull/14887))
+
 
 - Removed the deprecated `Trainer.lightning_optimizers` ([#14889](https://github.com/Lightning-AI/lightning/pull/14889))
 

src/pytorch_lightning/trainer/optimizers.py

@@ -1,65 +0,0 @@
-# Copyright The PyTorch Lightning team.
-#
-# 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.
-
-from abc import ABC
-from typing import List, Optional, Tuple
-
-from torch.optim import Optimizer
-
-import pytorch_lightning as pl
-from pytorch_lightning.core.optimizer import _init_optimizers_and_lr_schedulers, LightningOptimizer
-from pytorch_lightning.utilities.rank_zero import rank_zero_deprecation
-
-
-class TrainerOptimizersMixin(ABC):
-    r"""
-    .. deprecated:: v1.6
-        The `TrainerOptimizersMixin` was deprecated in v1.6 and will be removed in v1.8.
-    """
-
-    def init_optimizers(self, model: Optional["pl.LightningModule"]) -> Tuple[List, List, List]:
-        r"""
-        .. deprecated:: v1.6
-            `TrainerOptimizersMixin.init_optimizers` was deprecated in v1.6 and will be removed in v1.8.
-        """
-        rank_zero_deprecation(
-            "`TrainerOptimizersMixin.init_optimizers` was deprecated in v1.6 and will be removed in v1.8."
-        )
-        pl_module = self.lightning_module or model
-        assert isinstance(pl_module, pl.LightningModule)
-        return _init_optimizers_and_lr_schedulers(pl_module)
-
-    def convert_to_lightning_optimizers(self) -> None:
-        r"""
-        .. deprecated:: v1.6
-            `TrainerOptimizersMixin.convert_to_lightning_optimizers` was deprecated in v1.6 and will be removed in v1.8.
-        """
-        rank_zero_deprecation(
-            "`TrainerOptimizersMixin.convert_to_lightning_optimizers` was deprecated in v1.6 and will be removed in "
-            "v1.8."
-        )
-
-        def _convert_to_lightning_optimizer(optimizer: Optimizer) -> LightningOptimizer:
-            if not isinstance(optimizer, LightningOptimizer):
-                optimizer = LightningOptimizer(optimizer)  # type: ignore [assignment]
-            optimizer._trainer = self
-            for opt_idx, opt in enumerate(self.optimizers):
-                if opt == optimizer._optimizer:
-                    optimizer._optimizer_idx = opt_idx
-                    break
-            return optimizer  # type: ignore [return-value]
-
-        self.strategy._cached_lightning_optimizers = {
-            idx: _convert_to_lightning_optimizer(opt) for idx, opt in enumerate(self.optimizers)
-        }

src/pytorch_lightning/trainer/trainer.py

@@ -74,7 +74,6 @@ from pytorch_lightning.trainer.connectors.data_connector import DataConnector
 from pytorch_lightning.trainer.connectors.logger_connector import LoggerConnector
 from pytorch_lightning.trainer.connectors.logger_connector.result import _ResultCollection
 from pytorch_lightning.trainer.connectors.signal_connector import SignalConnector
-from pytorch_lightning.trainer.optimizers import TrainerOptimizersMixin
 from pytorch_lightning.trainer.states import RunningStage, TrainerFn, TrainerState, TrainerStatus
 from pytorch_lightning.trainer.supporters import CombinedLoader
 from pytorch_lightning.tuner.tuning import _TunerResult, Tuner
@@ -108,9 +107,7 @@ warnings.filterwarnings(
 )
 
 
-class Trainer(
+class Trainer:
-    TrainerOptimizersMixin,  # TODO: Remove in v1.8
-):
     @_defaults_from_env_vars
     def __init__(
         self,

tests/tests_pytorch/deprecated_api/test_remove_1-8.py

@@ -62,24 +62,6 @@ def test_v1_8_0_trainer_ckpt_path_attributes(fn_prefix: str):
         setattr(trainer, test_attr, "v")
 
 
-def test_v1_8_0_trainer_optimizers_mixin():
-    trainer = Trainer()
-    model = BoringModel()
-    trainer.strategy.connect(model)
-    trainer.lightning_module.trainer = trainer
-
-    with pytest.deprecated_call(
-        match=r"`TrainerOptimizersMixin.init_optimizers` was deprecated in v1.6 and will be removed in v1.8."
-    ):
-        trainer.init_optimizers(model)
-
-    with pytest.deprecated_call(
-        match=r"`TrainerOptimizersMixin.convert_to_lightning_optimizers` was deprecated in v1.6 and will be removed in "
-        "v1.8."
-    ):
-        trainer.convert_to_lightning_optimizers()
-
-
 def test_v_1_8_0_deprecated_device_stats_monitor_prefix_metric_keys():
     from pytorch_lightning.callbacks.device_stats_monitor import prefix_metric_keys