added checkpoint test on cpu

tests/test_models.py

@@ -43,6 +43,59 @@ def test_dp_output_reduce():
     assert reduced['b']['c'] == out['b']['c']
 
 
+def test_cpu_slurm_managed():
+    """
+    SLURM checkpointing works
+    :return:
+    """
+    hparams = get_hparams()
+    model = LightningTestModel(hparams)
+
+    trainer_options = dict(
+        max_nb_epochs=1,
+    )
+
+    save_dir = init_save_dir()
+
+    # exp file to get meta
+    exp = get_exp(False)
+    exp.argparse(hparams)
+    exp.save()
+
+    # exp file to get weights
+    checkpoint = ModelCheckpoint(save_dir)
+
+    # add these to the trainer options
+    trainer_options['checkpoint_callback'] = checkpoint
+    trainer_options['experiment'] = exp
+
+    # fit model
+    trainer = Trainer(**trainer_options)
+    result = trainer.fit(model)
+
+    # correct result and ok accuracy
+    assert result == 1, 'amp + ddp model failed to complete'
+
+    # test model loading with a map_location
+    pretrained_model = load_model(exp, save_dir, True)
+
+    # test model preds
+    run_prediction(model.test_dataloader, pretrained_model)
+
+    trainer.model = pretrained_model
+    trainer.optimizers = pretrained_model.configure_optimizers()
+
+    # test HPC loading / saving
+    trainer.hpc_save(save_dir, exp)
+    trainer.hpc_load(save_dir, on_gpu=False)
+
+    # test freeze on gpu
+    model.freeze()
+    model.unfreeze()
+
+    clear_save_dir()
+
+
 def test_amp_gpu_ddp_slurm_managed():
     """
     Make sure DDP + AMP work